OpenCloudOS-Kernel/net/sched/sch_sfq.c

941 lines
22 KiB
C
Raw Normal View History

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* net/sched/sch_sfq.c Stochastic Fairness Queueing discipline.
*
* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/jiffies.h>
#include <linux/string.h>
#include <linux/in.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/skbuff.h>
net/flow_dissector: switch to siphash UDP IPv6 packets auto flowlabels are using a 32bit secret (static u32 hashrnd in net/core/flow_dissector.c) and apply jhash() over fields known by the receivers. Attackers can easily infer the 32bit secret and use this information to identify a device and/or user, since this 32bit secret is only set at boot time. Really, using jhash() to generate cookies sent on the wire is a serious security concern. Trying to change the rol32(hash, 16) in ip6_make_flowlabel() would be a dead end. Trying to periodically change the secret (like in sch_sfq.c) could change paths taken in the network for long lived flows. Let's switch to siphash, as we did in commit df453700e8d8 ("inet: switch IP ID generator to siphash") Using a cryptographically strong pseudo random function will solve this privacy issue and more generally remove other weak points in the stack. Packet schedulers using skb_get_hash_perturb() benefit from this change. Fixes: b56774163f99 ("ipv6: Enable auto flow labels by default") Fixes: 42240901f7c4 ("ipv6: Implement different admin modes for automatic flow labels") Fixes: 67800f9b1f4e ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel") Fixes: cb1ce2ef387b ("ipv6: Implement automatic flow label generation on transmit") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jonathan Berger <jonathann1@walla.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Cc: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-22 22:57:46 +08:00
#include <linux/siphash.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
#include <net/pkt_cls.h>
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
#include <net/red.h>
/* Stochastic Fairness Queuing algorithm.
=======================================
Source:
Paul E. McKenney "Stochastic Fairness Queuing",
IEEE INFOCOMM'90 Proceedings, San Francisco, 1990.
Paul E. McKenney "Stochastic Fairness Queuing",
"Interworking: Research and Experience", v.2, 1991, p.113-131.
See also:
M. Shreedhar and George Varghese "Efficient Fair
Queuing using Deficit Round Robin", Proc. SIGCOMM 95.
This is not the thing that is usually called (W)FQ nowadays.
It does not use any timestamp mechanism, but instead
processes queues in round-robin order.
ADVANTAGE:
- It is very cheap. Both CPU and memory requirements are minimal.
DRAWBACKS:
- "Stochastic" -> It is not 100% fair.
When hash collisions occur, several flows are considered as one.
- "Round-robin" -> It introduces larger delays than virtual clock
based schemes, and should not be used for isolating interactive
traffic from non-interactive. It means, that this scheduler
should be used as leaf of CBQ or P3, which put interactive traffic
to higher priority band.
We still need true WFQ for top level CSZ, but using WFQ
for the best effort traffic is absolutely pointless:
SFQ is superior for this purpose.
IMPLEMENTATION:
This implementation limits :
- maximal queue length per flow to 127 packets.
- max mtu to 2^18-1;
- max 65408 flows,
- number of hash buckets to 65536.
It is easy to increase these values, but not in flight. */
#define SFQ_MAX_DEPTH 127 /* max number of packets per flow */
#define SFQ_DEFAULT_FLOWS 128
#define SFQ_MAX_FLOWS (0x10000 - SFQ_MAX_DEPTH - 1) /* max number of flows */
#define SFQ_EMPTY_SLOT 0xffff
#define SFQ_DEFAULT_HASH_DIVISOR 1024
/* We use 16 bits to store allot, and want to handle packets up to 64K
* Scale allot by 8 (1<<3) so that no overflow occurs.
*/
#define SFQ_ALLOT_SHIFT 3
#define SFQ_ALLOT_SIZE(X) DIV_ROUND_UP(X, 1 << SFQ_ALLOT_SHIFT)
/* This type should contain at least SFQ_MAX_DEPTH + 1 + SFQ_MAX_FLOWS values */
typedef u16 sfq_index;
/*
* We dont use pointers to save space.
* Small indexes [0 ... SFQ_MAX_FLOWS - 1] are 'pointers' to slots[] array
* while following values [SFQ_MAX_FLOWS ... SFQ_MAX_FLOWS + SFQ_MAX_DEPTH]
* are 'pointers' to dep[] array
*/
struct sfq_head {
sfq_index next;
sfq_index prev;
};
struct sfq_slot {
struct sk_buff *skblist_next;
struct sk_buff *skblist_prev;
sfq_index qlen; /* number of skbs in skblist */
sfq_index next; /* next slot in sfq RR chain */
struct sfq_head dep; /* anchor in dep[] chains */
unsigned short hash; /* hash value (index in ht[]) */
short allot; /* credit for this slot */
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
unsigned int backlog;
struct red_vars vars;
};
struct sfq_sched_data {
/* frequently used fields */
int limit; /* limit of total number of packets in this qdisc */
unsigned int divisor; /* number of slots in hash table */
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
u8 headdrop;
u8 maxdepth; /* limit of packets per flow */
net/flow_dissector: switch to siphash UDP IPv6 packets auto flowlabels are using a 32bit secret (static u32 hashrnd in net/core/flow_dissector.c) and apply jhash() over fields known by the receivers. Attackers can easily infer the 32bit secret and use this information to identify a device and/or user, since this 32bit secret is only set at boot time. Really, using jhash() to generate cookies sent on the wire is a serious security concern. Trying to change the rol32(hash, 16) in ip6_make_flowlabel() would be a dead end. Trying to periodically change the secret (like in sch_sfq.c) could change paths taken in the network for long lived flows. Let's switch to siphash, as we did in commit df453700e8d8 ("inet: switch IP ID generator to siphash") Using a cryptographically strong pseudo random function will solve this privacy issue and more generally remove other weak points in the stack. Packet schedulers using skb_get_hash_perturb() benefit from this change. Fixes: b56774163f99 ("ipv6: Enable auto flow labels by default") Fixes: 42240901f7c4 ("ipv6: Implement different admin modes for automatic flow labels") Fixes: 67800f9b1f4e ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel") Fixes: cb1ce2ef387b ("ipv6: Implement automatic flow label generation on transmit") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jonathan Berger <jonathann1@walla.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Cc: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-22 22:57:46 +08:00
siphash_key_t perturbation;
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
u8 cur_depth; /* depth of longest slot */
u8 flags;
unsigned short scaled_quantum; /* SFQ_ALLOT_SIZE(quantum) */
struct tcf_proto __rcu *filter_list;
struct tcf_block *block;
sfq_index *ht; /* Hash table ('divisor' slots) */
struct sfq_slot *slots; /* Flows table ('maxflows' entries) */
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
struct red_parms *red_parms;
struct tc_sfqred_stats stats;
struct sfq_slot *tail; /* current slot in round */
struct sfq_head dep[SFQ_MAX_DEPTH + 1];
/* Linked lists of slots, indexed by depth
* dep[0] : list of unused flows
* dep[1] : list of flows with 1 packet
* dep[X] : list of flows with X packets
*/
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
unsigned int maxflows; /* number of flows in flows array */
int perturb_period;
unsigned int quantum; /* Allotment per round: MUST BE >= MTU */
struct timer_list perturb_timer;
struct Qdisc *sch;
};
/*
* sfq_head are either in a sfq_slot or in dep[] array
*/
static inline struct sfq_head *sfq_dep_head(struct sfq_sched_data *q, sfq_index val)
{
if (val < SFQ_MAX_FLOWS)
return &q->slots[val].dep;
return &q->dep[val - SFQ_MAX_FLOWS];
}
static unsigned int sfq_hash(const struct sfq_sched_data *q,
const struct sk_buff *skb)
{
net/flow_dissector: switch to siphash UDP IPv6 packets auto flowlabels are using a 32bit secret (static u32 hashrnd in net/core/flow_dissector.c) and apply jhash() over fields known by the receivers. Attackers can easily infer the 32bit secret and use this information to identify a device and/or user, since this 32bit secret is only set at boot time. Really, using jhash() to generate cookies sent on the wire is a serious security concern. Trying to change the rol32(hash, 16) in ip6_make_flowlabel() would be a dead end. Trying to periodically change the secret (like in sch_sfq.c) could change paths taken in the network for long lived flows. Let's switch to siphash, as we did in commit df453700e8d8 ("inet: switch IP ID generator to siphash") Using a cryptographically strong pseudo random function will solve this privacy issue and more generally remove other weak points in the stack. Packet schedulers using skb_get_hash_perturb() benefit from this change. Fixes: b56774163f99 ("ipv6: Enable auto flow labels by default") Fixes: 42240901f7c4 ("ipv6: Implement different admin modes for automatic flow labels") Fixes: 67800f9b1f4e ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel") Fixes: cb1ce2ef387b ("ipv6: Implement automatic flow label generation on transmit") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jonathan Berger <jonathann1@walla.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Cc: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-22 22:57:46 +08:00
return skb_get_hash_perturb(skb, &q->perturbation) & (q->divisor - 1);
}
static unsigned int sfq_classify(struct sk_buff *skb, struct Qdisc *sch,
int *qerr)
{
struct sfq_sched_data *q = qdisc_priv(sch);
struct tcf_result res;
struct tcf_proto *fl;
int result;
if (TC_H_MAJ(skb->priority) == sch->handle &&
TC_H_MIN(skb->priority) > 0 &&
TC_H_MIN(skb->priority) <= q->divisor)
return TC_H_MIN(skb->priority);
fl = rcu_dereference_bh(q->filter_list);
if (!fl)
return sfq_hash(q, skb) + 1;
*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
result = tcf_classify(skb, fl, &res, false);
if (result >= 0) {
#ifdef CONFIG_NET_CLS_ACT
switch (result) {
case TC_ACT_STOLEN:
case TC_ACT_QUEUED:
case TC_ACT_TRAP:
*qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
fallthrough;
case TC_ACT_SHOT:
return 0;
}
#endif
if (TC_H_MIN(res.classid) <= q->divisor)
return TC_H_MIN(res.classid);
}
return 0;
}
/*
* x : slot number [0 .. SFQ_MAX_FLOWS - 1]
*/
static inline void sfq_link(struct sfq_sched_data *q, sfq_index x)
{
sfq_index p, n;
struct sfq_slot *slot = &q->slots[x];
int qlen = slot->qlen;
p = qlen + SFQ_MAX_FLOWS;
n = q->dep[qlen].next;
slot->dep.next = n;
slot->dep.prev = p;
q->dep[qlen].next = x; /* sfq_dep_head(q, p)->next = x */
sfq_dep_head(q, n)->prev = x;
}
#define sfq_unlink(q, x, n, p) \
do { \
n = q->slots[x].dep.next; \
p = q->slots[x].dep.prev; \
sfq_dep_head(q, p)->next = n; \
sfq_dep_head(q, n)->prev = p; \
} while (0)
static inline void sfq_dec(struct sfq_sched_data *q, sfq_index x)
{
sfq_index p, n;
int d;
sfq_unlink(q, x, n, p);
d = q->slots[x].qlen--;
if (n == p && q->cur_depth == d)
q->cur_depth--;
sfq_link(q, x);
}
static inline void sfq_inc(struct sfq_sched_data *q, sfq_index x)
{
sfq_index p, n;
int d;
sfq_unlink(q, x, n, p);
d = ++q->slots[x].qlen;
if (q->cur_depth < d)
q->cur_depth = d;
sfq_link(q, x);
}
/* helper functions : might be changed when/if skb use a standard list_head */
/* remove one skb from tail of slot queue */
static inline struct sk_buff *slot_dequeue_tail(struct sfq_slot *slot)
{
struct sk_buff *skb = slot->skblist_prev;
slot->skblist_prev = skb->prev;
skb->prev->next = (struct sk_buff *)slot;
skb->next = skb->prev = NULL;
return skb;
}
/* remove one skb from head of slot queue */
static inline struct sk_buff *slot_dequeue_head(struct sfq_slot *slot)
{
struct sk_buff *skb = slot->skblist_next;
slot->skblist_next = skb->next;
skb->next->prev = (struct sk_buff *)slot;
skb->next = skb->prev = NULL;
return skb;
}
static inline void slot_queue_init(struct sfq_slot *slot)
{
memset(slot, 0, sizeof(*slot));
slot->skblist_prev = slot->skblist_next = (struct sk_buff *)slot;
}
/* add skb to slot queue (tail add) */
static inline void slot_queue_add(struct sfq_slot *slot, struct sk_buff *skb)
{
skb->prev = slot->skblist_prev;
skb->next = (struct sk_buff *)slot;
slot->skblist_prev->next = skb;
slot->skblist_prev = skb;
}
static unsigned int sfq_drop(struct Qdisc *sch, struct sk_buff **to_free)
{
struct sfq_sched_data *q = qdisc_priv(sch);
sfq_index x, d = q->cur_depth;
struct sk_buff *skb;
unsigned int len;
struct sfq_slot *slot;
/* Queue is full! Find the longest slot and drop tail packet from it */
if (d > 1) {
x = q->dep[d].next;
slot = &q->slots[x];
drop:
skb = q->headdrop ? slot_dequeue_head(slot) : slot_dequeue_tail(slot);
len = qdisc_pkt_len(skb);
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
slot->backlog -= len;
sfq_dec(q, x);
sch->q.qlen--;
qdisc_qstats_backlog_dec(sch, skb);
qdisc_drop(skb, sch, to_free);
return len;
}
if (d == 1) {
/* It is difficult to believe, but ALL THE SLOTS HAVE LENGTH 1. */
x = q->tail->next;
slot = &q->slots[x];
q->tail->next = slot->next;
q->ht[slot->hash] = SFQ_EMPTY_SLOT;
goto drop;
}
return 0;
}
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
/* Is ECN parameter configured */
static int sfq_prob_mark(const struct sfq_sched_data *q)
{
return q->flags & TC_RED_ECN;
}
/* Should packets over max threshold just be marked */
static int sfq_hard_mark(const struct sfq_sched_data *q)
{
return (q->flags & (TC_RED_ECN | TC_RED_HARDDROP)) == TC_RED_ECN;
}
static int sfq_headdrop(const struct sfq_sched_data *q)
{
return q->headdrop;
}
static int
sfq_enqueue(struct sk_buff *skb, struct Qdisc *sch, struct sk_buff **to_free)
{
struct sfq_sched_data *q = qdisc_priv(sch);
unsigned int hash, dropped;
sfq_index x, qlen;
struct sfq_slot *slot;
int uninitialized_var(ret);
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
struct sk_buff *head;
int delta;
hash = sfq_classify(skb, sch, &ret);
if (hash == 0) {
if (ret & __NET_XMIT_BYPASS)
qdisc_qstats_drop(sch);
__qdisc_drop(skb, to_free);
return ret;
}
hash--;
x = q->ht[hash];
slot = &q->slots[x];
if (x == SFQ_EMPTY_SLOT) {
x = q->dep[0].next; /* get a free slot */
if (x >= SFQ_MAX_FLOWS)
return qdisc_drop(skb, sch, to_free);
q->ht[hash] = x;
slot = &q->slots[x];
slot->hash = hash;
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
slot->backlog = 0; /* should already be 0 anyway... */
red_set_vars(&slot->vars);
goto enqueue;
}
if (q->red_parms) {
slot->vars.qavg = red_calc_qavg_no_idle_time(q->red_parms,
&slot->vars,
slot->backlog);
switch (red_action(q->red_parms,
&slot->vars,
slot->vars.qavg)) {
case RED_DONT_MARK:
break;
case RED_PROB_MARK:
qdisc_qstats_overlimit(sch);
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
if (sfq_prob_mark(q)) {
/* We know we have at least one packet in queue */
if (sfq_headdrop(q) &&
INET_ECN_set_ce(slot->skblist_next)) {
q->stats.prob_mark_head++;
break;
}
if (INET_ECN_set_ce(skb)) {
q->stats.prob_mark++;
break;
}
}
q->stats.prob_drop++;
goto congestion_drop;
case RED_HARD_MARK:
qdisc_qstats_overlimit(sch);
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
if (sfq_hard_mark(q)) {
/* We know we have at least one packet in queue */
if (sfq_headdrop(q) &&
INET_ECN_set_ce(slot->skblist_next)) {
q->stats.forced_mark_head++;
break;
}
if (INET_ECN_set_ce(skb)) {
q->stats.forced_mark++;
break;
}
}
q->stats.forced_drop++;
goto congestion_drop;
}
}
if (slot->qlen >= q->maxdepth) {
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
congestion_drop:
if (!sfq_headdrop(q))
return qdisc_drop(skb, sch, to_free);
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
/* We know we have at least one packet in queue */
head = slot_dequeue_head(slot);
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
delta = qdisc_pkt_len(head) - qdisc_pkt_len(skb);
sch->qstats.backlog -= delta;
slot->backlog -= delta;
qdisc_drop(head, sch, to_free);
slot_queue_add(slot, skb);
qdisc_tree_reduce_backlog(sch, 0, delta);
return NET_XMIT_CN;
}
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
enqueue:
qdisc_qstats_backlog_inc(sch, skb);
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
slot->backlog += qdisc_pkt_len(skb);
slot_queue_add(slot, skb);
sfq_inc(q, x);
if (slot->qlen == 1) { /* The flow is new */
if (q->tail == NULL) { /* It is the first flow */
slot->next = x;
} else {
slot->next = q->tail->next;
q->tail->next = x;
}
/* We put this flow at the end of our flow list.
* This might sound unfair for a new flow to wait after old ones,
* but we could endup servicing new flows only, and freeze old ones.
*/
q->tail = slot;
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
/* We could use a bigger initial quantum for new flows */
slot->allot = q->scaled_quantum;
}
if (++sch->q.qlen <= q->limit)
return NET_XMIT_SUCCESS;
qlen = slot->qlen;
dropped = sfq_drop(sch, to_free);
/* Return Congestion Notification only if we dropped a packet
* from this flow.
*/
if (qlen != slot->qlen) {
qdisc_tree_reduce_backlog(sch, 0, dropped - qdisc_pkt_len(skb));
return NET_XMIT_CN;
}
/* As we dropped a packet, better let upper stack know this */
qdisc_tree_reduce_backlog(sch, 1, dropped);
return NET_XMIT_SUCCESS;
}
static struct sk_buff *
sfq_dequeue(struct Qdisc *sch)
{
struct sfq_sched_data *q = qdisc_priv(sch);
struct sk_buff *skb;
sfq_index a, next_a;
struct sfq_slot *slot;
/* No active slots */
if (q->tail == NULL)
return NULL;
next_slot:
a = q->tail->next;
slot = &q->slots[a];
if (slot->allot <= 0) {
q->tail = slot;
slot->allot += q->scaled_quantum;
goto next_slot;
}
skb = slot_dequeue_head(slot);
sfq_dec(q, a);
qdisc_bstats_update(sch, skb);
sch->q.qlen--;
qdisc_qstats_backlog_dec(sch, skb);
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
slot->backlog -= qdisc_pkt_len(skb);
/* Is the slot empty? */
if (slot->qlen == 0) {
q->ht[slot->hash] = SFQ_EMPTY_SLOT;
next_a = slot->next;
if (a == next_a) {
q->tail = NULL; /* no more active slots */
return skb;
}
q->tail->next = next_a;
} else {
slot->allot -= SFQ_ALLOT_SIZE(qdisc_pkt_len(skb));
}
return skb;
}
static void
sfq_reset(struct Qdisc *sch)
{
struct sk_buff *skb;
while ((skb = sfq_dequeue(sch)) != NULL)
rtnl_kfree_skbs(skb, skb);
}
/*
* When q->perturbation is changed, we rehash all queued skbs
* to avoid OOO (Out Of Order) effects.
* We dont use sfq_dequeue()/sfq_enqueue() because we dont want to change
* counters.
*/
static void sfq_rehash(struct Qdisc *sch)
{
struct sfq_sched_data *q = qdisc_priv(sch);
struct sk_buff *skb;
int i;
struct sfq_slot *slot;
struct sk_buff_head list;
int dropped = 0;
unsigned int drop_len = 0;
__skb_queue_head_init(&list);
for (i = 0; i < q->maxflows; i++) {
slot = &q->slots[i];
if (!slot->qlen)
continue;
while (slot->qlen) {
skb = slot_dequeue_head(slot);
sfq_dec(q, i);
__skb_queue_tail(&list, skb);
}
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
slot->backlog = 0;
red_set_vars(&slot->vars);
q->ht[slot->hash] = SFQ_EMPTY_SLOT;
}
q->tail = NULL;
while ((skb = __skb_dequeue(&list)) != NULL) {
unsigned int hash = sfq_hash(q, skb);
sfq_index x = q->ht[hash];
slot = &q->slots[x];
if (x == SFQ_EMPTY_SLOT) {
x = q->dep[0].next; /* get a free slot */
if (x >= SFQ_MAX_FLOWS) {
drop:
qdisc_qstats_backlog_dec(sch, skb);
drop_len += qdisc_pkt_len(skb);
kfree_skb(skb);
dropped++;
continue;
}
q->ht[hash] = x;
slot = &q->slots[x];
slot->hash = hash;
}
if (slot->qlen >= q->maxdepth)
goto drop;
slot_queue_add(slot, skb);
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
if (q->red_parms)
slot->vars.qavg = red_calc_qavg(q->red_parms,
&slot->vars,
slot->backlog);
slot->backlog += qdisc_pkt_len(skb);
sfq_inc(q, x);
if (slot->qlen == 1) { /* The flow is new */
if (q->tail == NULL) { /* It is the first flow */
slot->next = x;
} else {
slot->next = q->tail->next;
q->tail->next = x;
}
q->tail = slot;
slot->allot = q->scaled_quantum;
}
}
sch->q.qlen -= dropped;
qdisc_tree_reduce_backlog(sch, dropped, drop_len);
}
static void sfq_perturbation(struct timer_list *t)
{
struct sfq_sched_data *q = from_timer(q, t, perturb_timer);
struct Qdisc *sch = q->sch;
spinlock_t *root_lock = qdisc_lock(qdisc_root_sleeping(sch));
net/flow_dissector: switch to siphash UDP IPv6 packets auto flowlabels are using a 32bit secret (static u32 hashrnd in net/core/flow_dissector.c) and apply jhash() over fields known by the receivers. Attackers can easily infer the 32bit secret and use this information to identify a device and/or user, since this 32bit secret is only set at boot time. Really, using jhash() to generate cookies sent on the wire is a serious security concern. Trying to change the rol32(hash, 16) in ip6_make_flowlabel() would be a dead end. Trying to periodically change the secret (like in sch_sfq.c) could change paths taken in the network for long lived flows. Let's switch to siphash, as we did in commit df453700e8d8 ("inet: switch IP ID generator to siphash") Using a cryptographically strong pseudo random function will solve this privacy issue and more generally remove other weak points in the stack. Packet schedulers using skb_get_hash_perturb() benefit from this change. Fixes: b56774163f99 ("ipv6: Enable auto flow labels by default") Fixes: 42240901f7c4 ("ipv6: Implement different admin modes for automatic flow labels") Fixes: 67800f9b1f4e ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel") Fixes: cb1ce2ef387b ("ipv6: Implement automatic flow label generation on transmit") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jonathan Berger <jonathann1@walla.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Cc: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-22 22:57:46 +08:00
siphash_key_t nkey;
net/flow_dissector: switch to siphash UDP IPv6 packets auto flowlabels are using a 32bit secret (static u32 hashrnd in net/core/flow_dissector.c) and apply jhash() over fields known by the receivers. Attackers can easily infer the 32bit secret and use this information to identify a device and/or user, since this 32bit secret is only set at boot time. Really, using jhash() to generate cookies sent on the wire is a serious security concern. Trying to change the rol32(hash, 16) in ip6_make_flowlabel() would be a dead end. Trying to periodically change the secret (like in sch_sfq.c) could change paths taken in the network for long lived flows. Let's switch to siphash, as we did in commit df453700e8d8 ("inet: switch IP ID generator to siphash") Using a cryptographically strong pseudo random function will solve this privacy issue and more generally remove other weak points in the stack. Packet schedulers using skb_get_hash_perturb() benefit from this change. Fixes: b56774163f99 ("ipv6: Enable auto flow labels by default") Fixes: 42240901f7c4 ("ipv6: Implement different admin modes for automatic flow labels") Fixes: 67800f9b1f4e ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel") Fixes: cb1ce2ef387b ("ipv6: Implement automatic flow label generation on transmit") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jonathan Berger <jonathann1@walla.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Cc: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-22 22:57:46 +08:00
get_random_bytes(&nkey, sizeof(nkey));
spin_lock(root_lock);
net/flow_dissector: switch to siphash UDP IPv6 packets auto flowlabels are using a 32bit secret (static u32 hashrnd in net/core/flow_dissector.c) and apply jhash() over fields known by the receivers. Attackers can easily infer the 32bit secret and use this information to identify a device and/or user, since this 32bit secret is only set at boot time. Really, using jhash() to generate cookies sent on the wire is a serious security concern. Trying to change the rol32(hash, 16) in ip6_make_flowlabel() would be a dead end. Trying to periodically change the secret (like in sch_sfq.c) could change paths taken in the network for long lived flows. Let's switch to siphash, as we did in commit df453700e8d8 ("inet: switch IP ID generator to siphash") Using a cryptographically strong pseudo random function will solve this privacy issue and more generally remove other weak points in the stack. Packet schedulers using skb_get_hash_perturb() benefit from this change. Fixes: b56774163f99 ("ipv6: Enable auto flow labels by default") Fixes: 42240901f7c4 ("ipv6: Implement different admin modes for automatic flow labels") Fixes: 67800f9b1f4e ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel") Fixes: cb1ce2ef387b ("ipv6: Implement automatic flow label generation on transmit") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jonathan Berger <jonathann1@walla.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Cc: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-22 22:57:46 +08:00
q->perturbation = nkey;
if (!q->filter_list && q->tail)
sfq_rehash(sch);
spin_unlock(root_lock);
if (q->perturb_period)
mod_timer(&q->perturb_timer, jiffies + q->perturb_period);
}
static int sfq_change(struct Qdisc *sch, struct nlattr *opt)
{
struct sfq_sched_data *q = qdisc_priv(sch);
struct tc_sfq_qopt *ctl = nla_data(opt);
struct tc_sfq_qopt_v1 *ctl_v1 = NULL;
unsigned int qlen, dropped = 0;
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
struct red_parms *p = NULL;
struct sk_buff *to_free = NULL;
struct sk_buff *tail = NULL;
if (opt->nla_len < nla_attr_size(sizeof(*ctl)))
return -EINVAL;
if (opt->nla_len >= nla_attr_size(sizeof(*ctl_v1)))
ctl_v1 = nla_data(opt);
if (ctl->divisor &&
(!is_power_of_2(ctl->divisor) || ctl->divisor > 65536))
return -EINVAL;
/* slot->allot is a short, make sure quantum is not too big. */
if (ctl->quantum) {
unsigned int scaled = SFQ_ALLOT_SIZE(ctl->quantum);
if (scaled <= 0 || scaled > SHRT_MAX)
return -EINVAL;
}
if (ctl_v1 && !red_check_params(ctl_v1->qth_min, ctl_v1->qth_max,
ctl_v1->Wlog))
return -EINVAL;
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
if (ctl_v1 && ctl_v1->qth_min) {
p = kmalloc(sizeof(*p), GFP_KERNEL);
if (!p)
return -ENOMEM;
}
sch_tree_lock(sch);
if (ctl->quantum) {
q->quantum = ctl->quantum;
q->scaled_quantum = SFQ_ALLOT_SIZE(q->quantum);
}
q->perturb_period = ctl->perturb_period * HZ;
if (ctl->flows)
q->maxflows = min_t(u32, ctl->flows, SFQ_MAX_FLOWS);
if (ctl->divisor) {
q->divisor = ctl->divisor;
q->maxflows = min_t(u32, q->maxflows, q->divisor);
}
if (ctl_v1) {
if (ctl_v1->depth)
q->maxdepth = min_t(u32, ctl_v1->depth, SFQ_MAX_DEPTH);
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
if (p) {
swap(q->red_parms, p);
red_set_parms(q->red_parms,
ctl_v1->qth_min, ctl_v1->qth_max,
ctl_v1->Wlog,
ctl_v1->Plog, ctl_v1->Scell_log,
NULL,
ctl_v1->max_P);
}
q->flags = ctl_v1->flags;
q->headdrop = ctl_v1->headdrop;
}
if (ctl->limit) {
q->limit = min_t(u32, ctl->limit, q->maxdepth * q->maxflows);
q->maxflows = min_t(u32, q->maxflows, q->limit);
}
qlen = sch->q.qlen;
while (sch->q.qlen > q->limit) {
dropped += sfq_drop(sch, &to_free);
if (!tail)
tail = to_free;
}
rtnl_kfree_skbs(to_free, tail);
qdisc_tree_reduce_backlog(sch, qlen - sch->q.qlen, dropped);
del_timer(&q->perturb_timer);
if (q->perturb_period) {
mod_timer(&q->perturb_timer, jiffies + q->perturb_period);
net/flow_dissector: switch to siphash UDP IPv6 packets auto flowlabels are using a 32bit secret (static u32 hashrnd in net/core/flow_dissector.c) and apply jhash() over fields known by the receivers. Attackers can easily infer the 32bit secret and use this information to identify a device and/or user, since this 32bit secret is only set at boot time. Really, using jhash() to generate cookies sent on the wire is a serious security concern. Trying to change the rol32(hash, 16) in ip6_make_flowlabel() would be a dead end. Trying to periodically change the secret (like in sch_sfq.c) could change paths taken in the network for long lived flows. Let's switch to siphash, as we did in commit df453700e8d8 ("inet: switch IP ID generator to siphash") Using a cryptographically strong pseudo random function will solve this privacy issue and more generally remove other weak points in the stack. Packet schedulers using skb_get_hash_perturb() benefit from this change. Fixes: b56774163f99 ("ipv6: Enable auto flow labels by default") Fixes: 42240901f7c4 ("ipv6: Implement different admin modes for automatic flow labels") Fixes: 67800f9b1f4e ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel") Fixes: cb1ce2ef387b ("ipv6: Implement automatic flow label generation on transmit") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jonathan Berger <jonathann1@walla.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Cc: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-22 22:57:46 +08:00
get_random_bytes(&q->perturbation, sizeof(q->perturbation));
}
sch_tree_unlock(sch);
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
kfree(p);
return 0;
}
static void *sfq_alloc(size_t sz)
{
treewide: use kv[mz]alloc* rather than opencoded variants There are many code paths opencoding kvmalloc. Let's use the helper instead. The main difference to kvmalloc is that those users are usually not considering all the aspects of the memory allocator. E.g. allocation requests <= 32kB (with 4kB pages) are basically never failing and invoke OOM killer to satisfy the allocation. This sounds too disruptive for something that has a reasonable fallback - the vmalloc. On the other hand those requests might fallback to vmalloc even when the memory allocator would succeed after several more reclaim/compaction attempts previously. There is no guarantee something like that happens though. This patch converts many of those places to kv[mz]alloc* helpers because they are more conservative. Link: http://lkml.kernel.org/r/20170306103327.2766-2-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> # Xen bits Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Andreas Dilger <andreas.dilger@intel.com> # Lustre Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> # KVM/s390 Acked-by: Dan Williams <dan.j.williams@intel.com> # nvdim Acked-by: David Sterba <dsterba@suse.com> # btrfs Acked-by: Ilya Dryomov <idryomov@gmail.com> # Ceph Acked-by: Tariq Toukan <tariqt@mellanox.com> # mlx4 Acked-by: Leon Romanovsky <leonro@mellanox.com> # mlx5 Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Tony Luck <tony.luck@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: Kent Overstreet <kent.overstreet@gmail.com> Cc: Santosh Raspatur <santosh@chelsio.com> Cc: Hariprasad S <hariprasad@chelsio.com> Cc: Yishai Hadas <yishaih@mellanox.com> Cc: Oleg Drokin <oleg.drokin@intel.com> Cc: "Yan, Zheng" <zyan@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-09 06:57:27 +08:00
return kvmalloc(sz, GFP_KERNEL);
}
static void sfq_free(void *addr)
{
kvfree(addr);
}
static void sfq_destroy(struct Qdisc *sch)
{
struct sfq_sched_data *q = qdisc_priv(sch);
tcf_block_put(q->block);
q->perturb_period = 0;
del_timer_sync(&q->perturb_timer);
sfq_free(q->ht);
sfq_free(q->slots);
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
kfree(q->red_parms);
}
static int sfq_init(struct Qdisc *sch, struct nlattr *opt,
struct netlink_ext_ack *extack)
{
struct sfq_sched_data *q = qdisc_priv(sch);
int i;
int err;
q->sch = sch;
timer_setup(&q->perturb_timer, sfq_perturbation, TIMER_DEFERRABLE);
err = tcf_block_get(&q->block, &q->filter_list, sch, extack);
if (err)
return err;
for (i = 0; i < SFQ_MAX_DEPTH + 1; i++) {
q->dep[i].next = i + SFQ_MAX_FLOWS;
q->dep[i].prev = i + SFQ_MAX_FLOWS;
}
q->limit = SFQ_MAX_DEPTH;
q->maxdepth = SFQ_MAX_DEPTH;
q->cur_depth = 0;
q->tail = NULL;
q->divisor = SFQ_DEFAULT_HASH_DIVISOR;
q->maxflows = SFQ_DEFAULT_FLOWS;
q->quantum = psched_mtu(qdisc_dev(sch));
q->scaled_quantum = SFQ_ALLOT_SIZE(q->quantum);
q->perturb_period = 0;
net/flow_dissector: switch to siphash UDP IPv6 packets auto flowlabels are using a 32bit secret (static u32 hashrnd in net/core/flow_dissector.c) and apply jhash() over fields known by the receivers. Attackers can easily infer the 32bit secret and use this information to identify a device and/or user, since this 32bit secret is only set at boot time. Really, using jhash() to generate cookies sent on the wire is a serious security concern. Trying to change the rol32(hash, 16) in ip6_make_flowlabel() would be a dead end. Trying to periodically change the secret (like in sch_sfq.c) could change paths taken in the network for long lived flows. Let's switch to siphash, as we did in commit df453700e8d8 ("inet: switch IP ID generator to siphash") Using a cryptographically strong pseudo random function will solve this privacy issue and more generally remove other weak points in the stack. Packet schedulers using skb_get_hash_perturb() benefit from this change. Fixes: b56774163f99 ("ipv6: Enable auto flow labels by default") Fixes: 42240901f7c4 ("ipv6: Implement different admin modes for automatic flow labels") Fixes: 67800f9b1f4e ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel") Fixes: cb1ce2ef387b ("ipv6: Implement automatic flow label generation on transmit") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jonathan Berger <jonathann1@walla.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Cc: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-22 22:57:46 +08:00
get_random_bytes(&q->perturbation, sizeof(q->perturbation));
if (opt) {
int err = sfq_change(sch, opt);
if (err)
return err;
}
q->ht = sfq_alloc(sizeof(q->ht[0]) * q->divisor);
q->slots = sfq_alloc(sizeof(q->slots[0]) * q->maxflows);
if (!q->ht || !q->slots) {
net_sched: fix error recovery at qdisc creation Dmitry reported uses after free in qdisc code [1] The problem here is that ops->init() can return an error. qdisc_create_dflt() then call ops->destroy(), while qdisc_create() does _not_ call it. Four qdisc chose to call their own ops->destroy(), assuming their caller would not. This patch makes sure qdisc_create() calls ops->destroy() and fixes the four qdisc to avoid double free. [1] BUG: KASAN: use-after-free in mq_destroy+0x242/0x290 net/sched/sch_mq.c:33 at addr ffff8801d415d440 Read of size 8 by task syz-executor2/5030 CPU: 0 PID: 5030 Comm: syz-executor2 Not tainted 4.3.5-smp-DEV #119 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 0000000000000046 ffff8801b435b870 ffffffff81bbbed4 ffff8801db000400 ffff8801d415d440 ffff8801d415dc40 ffff8801c4988510 ffff8801b435b898 ffffffff816682b1 ffff8801b435b928 ffff8801d415d440 ffff8801c49880c0 Call Trace: [<ffffffff81bbbed4>] __dump_stack lib/dump_stack.c:15 [inline] [<ffffffff81bbbed4>] dump_stack+0x6c/0x98 lib/dump_stack.c:51 [<ffffffff816682b1>] kasan_object_err+0x21/0x70 mm/kasan/report.c:158 [<ffffffff81668524>] print_address_description mm/kasan/report.c:196 [inline] [<ffffffff81668524>] kasan_report_error+0x1b4/0x4b0 mm/kasan/report.c:285 [<ffffffff81668953>] kasan_report mm/kasan/report.c:305 [inline] [<ffffffff81668953>] __asan_report_load8_noabort+0x43/0x50 mm/kasan/report.c:326 [<ffffffff82527b02>] mq_destroy+0x242/0x290 net/sched/sch_mq.c:33 [<ffffffff82524bdd>] qdisc_destroy+0x12d/0x290 net/sched/sch_generic.c:953 [<ffffffff82524e30>] qdisc_create_dflt+0xf0/0x120 net/sched/sch_generic.c:848 [<ffffffff8252550d>] attach_default_qdiscs net/sched/sch_generic.c:1029 [inline] [<ffffffff8252550d>] dev_activate+0x6ad/0x880 net/sched/sch_generic.c:1064 [<ffffffff824b1db1>] __dev_open+0x221/0x320 net/core/dev.c:1403 [<ffffffff824b24ce>] __dev_change_flags+0x15e/0x3e0 net/core/dev.c:6858 [<ffffffff824b27de>] dev_change_flags+0x8e/0x140 net/core/dev.c:6926 [<ffffffff824f5bf6>] dev_ifsioc+0x446/0x890 net/core/dev_ioctl.c:260 [<ffffffff824f61fa>] dev_ioctl+0x1ba/0xb80 net/core/dev_ioctl.c:546 [<ffffffff82430509>] sock_do_ioctl+0x99/0xb0 net/socket.c:879 [<ffffffff82430d30>] sock_ioctl+0x2a0/0x390 net/socket.c:958 [<ffffffff816f3b68>] vfs_ioctl fs/ioctl.c:44 [inline] [<ffffffff816f3b68>] do_vfs_ioctl+0x8a8/0xe50 fs/ioctl.c:611 [<ffffffff816f41a4>] SYSC_ioctl fs/ioctl.c:626 [inline] [<ffffffff816f41a4>] SyS_ioctl+0x94/0xc0 fs/ioctl.c:617 [<ffffffff8123e357>] entry_SYSCALL_64_fastpath+0x12/0x17 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-11 02:31:49 +08:00
/* Note: sfq_destroy() will be called by our caller */
return -ENOMEM;
}
net_sched: fix error recovery at qdisc creation Dmitry reported uses after free in qdisc code [1] The problem here is that ops->init() can return an error. qdisc_create_dflt() then call ops->destroy(), while qdisc_create() does _not_ call it. Four qdisc chose to call their own ops->destroy(), assuming their caller would not. This patch makes sure qdisc_create() calls ops->destroy() and fixes the four qdisc to avoid double free. [1] BUG: KASAN: use-after-free in mq_destroy+0x242/0x290 net/sched/sch_mq.c:33 at addr ffff8801d415d440 Read of size 8 by task syz-executor2/5030 CPU: 0 PID: 5030 Comm: syz-executor2 Not tainted 4.3.5-smp-DEV #119 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 0000000000000046 ffff8801b435b870 ffffffff81bbbed4 ffff8801db000400 ffff8801d415d440 ffff8801d415dc40 ffff8801c4988510 ffff8801b435b898 ffffffff816682b1 ffff8801b435b928 ffff8801d415d440 ffff8801c49880c0 Call Trace: [<ffffffff81bbbed4>] __dump_stack lib/dump_stack.c:15 [inline] [<ffffffff81bbbed4>] dump_stack+0x6c/0x98 lib/dump_stack.c:51 [<ffffffff816682b1>] kasan_object_err+0x21/0x70 mm/kasan/report.c:158 [<ffffffff81668524>] print_address_description mm/kasan/report.c:196 [inline] [<ffffffff81668524>] kasan_report_error+0x1b4/0x4b0 mm/kasan/report.c:285 [<ffffffff81668953>] kasan_report mm/kasan/report.c:305 [inline] [<ffffffff81668953>] __asan_report_load8_noabort+0x43/0x50 mm/kasan/report.c:326 [<ffffffff82527b02>] mq_destroy+0x242/0x290 net/sched/sch_mq.c:33 [<ffffffff82524bdd>] qdisc_destroy+0x12d/0x290 net/sched/sch_generic.c:953 [<ffffffff82524e30>] qdisc_create_dflt+0xf0/0x120 net/sched/sch_generic.c:848 [<ffffffff8252550d>] attach_default_qdiscs net/sched/sch_generic.c:1029 [inline] [<ffffffff8252550d>] dev_activate+0x6ad/0x880 net/sched/sch_generic.c:1064 [<ffffffff824b1db1>] __dev_open+0x221/0x320 net/core/dev.c:1403 [<ffffffff824b24ce>] __dev_change_flags+0x15e/0x3e0 net/core/dev.c:6858 [<ffffffff824b27de>] dev_change_flags+0x8e/0x140 net/core/dev.c:6926 [<ffffffff824f5bf6>] dev_ifsioc+0x446/0x890 net/core/dev_ioctl.c:260 [<ffffffff824f61fa>] dev_ioctl+0x1ba/0xb80 net/core/dev_ioctl.c:546 [<ffffffff82430509>] sock_do_ioctl+0x99/0xb0 net/socket.c:879 [<ffffffff82430d30>] sock_ioctl+0x2a0/0x390 net/socket.c:958 [<ffffffff816f3b68>] vfs_ioctl fs/ioctl.c:44 [inline] [<ffffffff816f3b68>] do_vfs_ioctl+0x8a8/0xe50 fs/ioctl.c:611 [<ffffffff816f41a4>] SYSC_ioctl fs/ioctl.c:626 [inline] [<ffffffff816f41a4>] SyS_ioctl+0x94/0xc0 fs/ioctl.c:617 [<ffffffff8123e357>] entry_SYSCALL_64_fastpath+0x12/0x17 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-11 02:31:49 +08:00
for (i = 0; i < q->divisor; i++)
q->ht[i] = SFQ_EMPTY_SLOT;
for (i = 0; i < q->maxflows; i++) {
slot_queue_init(&q->slots[i]);
sfq_link(q, i);
}
if (q->limit >= 1)
sch->flags |= TCQ_F_CAN_BYPASS;
else
sch->flags &= ~TCQ_F_CAN_BYPASS;
return 0;
}
static int sfq_dump(struct Qdisc *sch, struct sk_buff *skb)
{
struct sfq_sched_data *q = qdisc_priv(sch);
unsigned char *b = skb_tail_pointer(skb);
struct tc_sfq_qopt_v1 opt;
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
struct red_parms *p = q->red_parms;
memset(&opt, 0, sizeof(opt));
opt.v0.quantum = q->quantum;
opt.v0.perturb_period = q->perturb_period / HZ;
opt.v0.limit = q->limit;
opt.v0.divisor = q->divisor;
opt.v0.flows = q->maxflows;
opt.depth = q->maxdepth;
opt.headdrop = q->headdrop;
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
if (p) {
opt.qth_min = p->qth_min >> p->Wlog;
opt.qth_max = p->qth_max >> p->Wlog;
opt.Wlog = p->Wlog;
opt.Plog = p->Plog;
opt.Scell_log = p->Scell_log;
opt.max_P = p->max_P;
}
memcpy(&opt.stats, &q->stats, sizeof(opt.stats));
opt.flags = q->flags;
if (nla_put(skb, TCA_OPTIONS, sizeof(opt), &opt))
goto nla_put_failure;
return skb->len;
nla_put_failure:
nlmsg_trim(skb, b);
return -1;
}
static struct Qdisc *sfq_leaf(struct Qdisc *sch, unsigned long arg)
{
return NULL;
}
static unsigned long sfq_find(struct Qdisc *sch, u32 classid)
{
return 0;
}
static unsigned long sfq_bind(struct Qdisc *sch, unsigned long parent,
u32 classid)
{
return 0;
}
static void sfq_unbind(struct Qdisc *q, unsigned long cl)
{
}
static struct tcf_block *sfq_tcf_block(struct Qdisc *sch, unsigned long cl,
struct netlink_ext_ack *extack)
{
struct sfq_sched_data *q = qdisc_priv(sch);
if (cl)
return NULL;
return q->block;
}
static int sfq_dump_class(struct Qdisc *sch, unsigned long cl,
struct sk_buff *skb, struct tcmsg *tcm)
{
tcm->tcm_handle |= TC_H_MIN(cl);
return 0;
}
static int sfq_dump_class_stats(struct Qdisc *sch, unsigned long cl,
struct gnet_dump *d)
{
struct sfq_sched_data *q = qdisc_priv(sch);
sfq_index idx = q->ht[cl - 1];
struct gnet_stats_queue qs = { 0 };
struct tc_sfq_xstats xstats = { 0 };
if (idx != SFQ_EMPTY_SLOT) {
const struct sfq_slot *slot = &q->slots[idx];
xstats.allot = slot->allot << SFQ_ALLOT_SHIFT;
qs.qlen = slot->qlen;
net_sched: sfq: add optional RED on top of SFQ Adds an optional Random Early Detection on each SFQ flow queue. Traditional SFQ limits count of packets, while RED permits to also control number of bytes per flow, and adds ECN capability as well. 1) We dont handle the idle time management in this RED implementation, since each 'new flow' begins with a null qavg. We really want to address backlogged flows. 2) if headdrop is selected, we try to ecn mark first packet instead of currently enqueued packet. This gives faster feedback for tcp flows compared to traditional RED [ marking the last packet in queue ] Example of use : tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \ limit 3000 headdrop flows 512 divisor 16384 \ redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 ewma 6 min 8000b max 60000b probability 0.2 ecn prob_mark 0 prob_mark_head 4876 prob_drop 6131 forced_mark 0 forced_mark_head 0 forced_drop 0 Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007 requeues 0) rate 99483Kbit 8219pps backlog 689392b 456p requeues 0 In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled flows, we can see number of packets CE marked is smaller than number of drops (for non ECN flows) If same test is run, without RED, we can check backlog is much bigger. qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop flows 512/16384 divisor 16384 Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0) rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Tested-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-06 14:31:44 +08:00
qs.backlog = slot->backlog;
}
if (gnet_stats_copy_queue(d, NULL, &qs, qs.qlen) < 0)
return -1;
return gnet_stats_copy_app(d, &xstats, sizeof(xstats));
}
static void sfq_walk(struct Qdisc *sch, struct qdisc_walker *arg)
{
struct sfq_sched_data *q = qdisc_priv(sch);
unsigned int i;
if (arg->stop)
return;
for (i = 0; i < q->divisor; i++) {
if (q->ht[i] == SFQ_EMPTY_SLOT ||
arg->count < arg->skip) {
arg->count++;
continue;
}
if (arg->fn(sch, i + 1, arg) < 0) {
arg->stop = 1;
break;
}
arg->count++;
}
}
static const struct Qdisc_class_ops sfq_class_ops = {
.leaf = sfq_leaf,
.find = sfq_find,
.tcf_block = sfq_tcf_block,
.bind_tcf = sfq_bind,
.unbind_tcf = sfq_unbind,
.dump = sfq_dump_class,
.dump_stats = sfq_dump_class_stats,
.walk = sfq_walk,
};
static struct Qdisc_ops sfq_qdisc_ops __read_mostly = {
.cl_ops = &sfq_class_ops,
.id = "sfq",
.priv_size = sizeof(struct sfq_sched_data),
.enqueue = sfq_enqueue,
.dequeue = sfq_dequeue,
.peek = qdisc_peek_dequeued,
.init = sfq_init,
.reset = sfq_reset,
.destroy = sfq_destroy,
.change = NULL,
.dump = sfq_dump,
.owner = THIS_MODULE,
};
static int __init sfq_module_init(void)
{
return register_qdisc(&sfq_qdisc_ops);
}
static void __exit sfq_module_exit(void)
{
unregister_qdisc(&sfq_qdisc_ops);
}
module_init(sfq_module_init)
module_exit(sfq_module_exit)
MODULE_LICENSE("GPL");