Syzbot reported ODEBUG warning in batadv_nc_mesh_free(). The problem was
in wrong error handling in batadv_mesh_init().
Before this patch batadv_mesh_init() was calling batadv_mesh_free() in case
of any batadv_*_init() calls failure. This approach may work well, when
there is some kind of indicator, which can tell which parts of batadv are
initialized; but there isn't any.
All written above lead to cleaning up uninitialized fields. Even if we hide
ODEBUG warning by initializing bat_priv->nc.work, syzbot was able to hit
GPF in batadv_nc_purge_paths(), because hash pointer in still NULL. [1]
To fix these bugs we can unwind batadv_*_init() calls one by one.
It is good approach for 2 reasons: 1) It fixes bugs on error handling
path 2) It improves the performance, since we won't call unneeded
batadv_*_free() functions.
So, this patch makes all batadv_*_init() clean up all allocated memory
before returning with an error to no call correspoing batadv_*_free()
and open-codes batadv_mesh_free() with proper order to avoid touching
uninitialized fields.
Link: https://lore.kernel.org/netdev/000000000000c87fbd05cef6bcb0@google.com/ [1]
Reported-and-tested-by: syzbot+28b0702ada0bf7381f58@syzkaller.appspotmail.com
Fixes: c6c8fea297 ("net: Add batman-adv meshing protocol")
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Acked-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The check if a batman-adv related object is NULL or not is now directly in
the batadv_*_put functions. It is not needed anymore to perform this check
outside these function:
The changes were generated using a coccinelle semantic patch:
@@
expression E;
@@
- if (likely(E != NULL))
(
batadv_backbone_gw_put
|
batadv_claim_put
|
batadv_dat_entry_put
|
batadv_gw_node_put
|
batadv_hardif_neigh_put
|
batadv_hardif_put
|
batadv_nc_node_put
|
batadv_nc_path_put
|
batadv_neigh_ifinfo_put
|
batadv_neigh_node_put
|
batadv_orig_ifinfo_put
|
batadv_orig_node_put
|
batadv_orig_node_vlan_put
|
batadv_softif_vlan_put
|
batadv_tp_vars_put
|
batadv_tt_global_entry_put
|
batadv_tt_local_entry_put
|
batadv_tt_orig_list_entry_put
|
batadv_tt_req_node_put
|
batadv_tvlv_container_put
|
batadv_tvlv_handler_put
)(E);
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The commit b37a466837 ("netdevice: add the case if dev is NULL") changed
the way how the NULL check for net_devices have to be handled when trying
to reduce its reference counter. Before this commit, it was the
responsibility of the caller to check whether the object is NULL or not.
But it was changed to behave more like kfree. Now the callee has to handle
the NULL-case.
The batman-adv code was scanned via cocinelle for similar places. These
were changed to use the paradigm
@@
identifier E, T, R, C;
identifier put;
@@
void put(struct T *E)
{
+ if (!E)
+ return;
kref_put(&E->C, R);
}
Functions which were used in other sources files were moved to the header
to allow the compiler to inline the NULL check and the kref_put call.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The batman-adv source code was using the year of publication (to net-next)
as "last" year for the copyright statement. The whole source code mentioned
in the MAINTAINERS "BATMAN ADVANCED" section was handled as a single entity
regarding the publishing year.
This avoided having outdated (in sense of year information - not copyright
holder) publishing information inside several files. But since the simple
"update copyright year" commit (without other changes) in the file was not
well received in the upstream kernel, the option to not have a copyright
year (for initial and last publication) in the files are chosen instead.
More detailed information about the years can still be retrieved from the
SCM system.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The debugfs support in batman-adv was marked as deprecated by the commit
00caf6a2b3 ("batman-adv: Mark debugfs functionality as deprecated") and
scheduled for removal in 2021.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The commit c0842fbc1b ("random32: move the pseudo-random 32-bit
definitions to prandom.h") introduced a new header for the pseudo random
functions from (previously) linux/random.h. One future goal of the
prandom.h change is to make code to switch just the new header file and to
avoid the implicit include. This would allow the removal of the implicit
include from random.h
Signed-off-by: Sven Eckelmann <sven@narfation.org>
checkpatch found various instances of "Possible repeated word" in various
comments.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
and change to pseudorandom numbers, as this is a traffic dithering
operation that doesn't need crypto-grade.
The previous code operated in 4 steps:
1. Generate a random byte 0 <= rand_tq <= 255
2. Multiply it by BATADV_TQ_MAX_VALUE - tq
3. Divide by 255 (= BATADV_TQ_MAX_VALUE)
4. Return BATADV_TQ_MAX_VALUE - rand_tq
This would apperar to scale (BATADV_TQ_MAX_VALUE - tq) by a random
value between 0/255 and 255/255.
But! The intermediate value between steps 3 and 4 is stored in a u8
variable. So it's truncated, and most of the time, is less than 255, after
which the division produces 0. Specifically, if tq is odd, the product is
always even, and can never be 255. If tq is even, there's exactly one
random byte value that will produce a product byte of 255.
Thus, the return value is 255 (511/512 of the time) or 254 (1/512
of the time).
If we assume that the truncation is a bug, and the code is meant to scale
the input, a simpler way of looking at it is that it's returning a random
value between tq and BATADV_TQ_MAX_VALUE, inclusive.
Well, we have an optimized function for doing just that.
Fixes: 3c12de9a5c ("batman-adv: network coding - code and transmit packets if possible")
Signed-off-by: George Spelvin <lkml@sdf.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
Because we don't care if debugfs works or not, this trickles back a bit
so we can clean things up by making some functions return void instead
of an error value that is never going to fail.
Cc: Marek Lindner <mareklindner@neomailbox.ch>
Cc: Simon Wunderlich <sw@simonwunderlich.de>
Cc: Antonio Quartulli <a@unstable.cc>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: b.a.t.m.a.n@lists.open-mesh.org
Cc: netdev@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[sven@narfation.org: drop unused variables]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
All files got a SPDX-License-Identifier with commit 7db7d9f369
("batman-adv: Add SPDX license identifier above copyright header"). All the
required information about the license conditions can be found in
LICENSES/.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The function batadv_nc_get_nc_node is responsible for adding new nc_nodes
to the in_coding_list and out_coding_list. It first checks whether the
entry already is in the list or not. If it is, then the creation of a new
entry is aborted.
But the lock for the list is only held when the list is really modified.
This could lead to duplicated entries because another context could create
an entry with the same key between the check and the list manipulation.
The check and the manipulation of the list must therefore be in the same
locked code section.
Fixes: d56b1705e2 ("batman-adv: network coding - detect coding nodes and remove these after timeout")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The header file is used by different userspace programs to inject packets
or to decode sniffed packets. It should therefore be available to them as
userspace header.
Also other components in the kernel (like the flow dissector) require
access to the packet definitions to be able to decode ETH_P_BATMAN ethernet
packets.
Signed-off-by: Sven Eckelmann <sven.eckelmann@openmesh.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The documentation describing kernel-doc comments for functions ("How to
format kernel-doc comments") uses parentheses at the end of the function
name. Using this format allows to use a consistent style when adding
documentation to a function and when referencing this function in a
different kernel-doc section.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The linux/net.h provides the net_ratelimited_function. It should
therefore be included directly before it is used.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The linux/gfp.h provides the GFP_ATOMIC and GFP_KERNEL define. It should
therefore be included instead of linux/fs.h.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The "Linux kernel licensing rules" require that each file has a SPDX
license identifier as first line (and sometimes as second line).
The FSFE REUSE practices [1] would also require the same tags but have no
restrictions on the placement in the source file. Using the "Linux kernel
licensing rules" is therefore also fulfilling the FSFE REUSE practices
requirements at the same time.
[1] https://reuse.software/practices/
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
A bit of text was put into a sequence by two separate function calls.
Print the same data by a single function call instead.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Receiving functions in Linux consume the supplied skbuff. Doing the same in
the batadv_rx_handler functions makes the behavior more similar to the rest
of the Linux network code.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
kfree_skb assumes that an skb is dropped after an failure and notes that.
consume_skb should be used in non-failure situations. Such information is
important for dropmonitor netlink which tells how many packets were dropped
and where this drop happened.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Linus prefers to have octal permission numbers instead of combinations of
macro names ("random line noise"). Also old existing "bad symbolic
permission bit macro use" should be converted to octal numbers.
(http://lkml.kernel.org/r/CA+55aFw5v23T-zvDZp-MmD_EYxF8WbafwwB59934FV7g21uMGQ@mail.gmail.com)
Also remove the S_IFREG bit from the octal representation because it is
filtered out by debugfs_create.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The files provided by batman-adv via debugfs are currently converted to
netlink. Tools which are not yet converted to use the netlink interface may
still rely on the old debugfs files. But systems which already upgraded
their tools can save some space by disabling this feature. The default
configuration of batman-adv on amd64 can reduce the size of the module by
around 11% when this feature is disabled.
$ size net/batman-adv/batman-adv.ko*
text data bss dec hex filename
150507 10395 4160 165062 284c6 net/batman-adv/batman-adv.ko.y
137106 7099 2112 146317 23b8d net/batman-adv/batman-adv.ko.n
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
It is hard to understand why the refcnt is increased when it isn't done
near the actual place the new reference is used. So using kref_get right
before the place which requires the reference and in the same function
helps to avoid accidental problems caused by incorrect reference counting.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
It is hard to understand why the refcnt is increased when it isn't done
near the actual place the new reference is used. So using kref_get right
before the place which requires the reference and in the same function
helps to avoid accidental problems caused by incorrect reference counting.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
It is hard to understand why the refcnt is increased when it isn't done
near the actual place the new reference is used. So using kref_get right
before the place which requires the reference and in the same function
helps to avoid accidental problems caused by incorrect reference counting.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
There are several places in batman-adv which provide logging related
functions. These should be grouped together in the log.* files to make them
easier to find.
Reported-by: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The tvlv functionality in main.c is mostly unrelated to the rest of the
content. It still takes up a large portion of this source file (~45%, 588
lines). Moving it to a separate file makes it better visible as a main
component of the batman-adv implementation and hides it less in the other
helper functions in main.c
Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
[sven@narfation.org: fix conflicts with current version, fix includes,
rewrote commit message]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
When comparing Ethernet address it is better to use the more
generic batadv_compare_eth. The latter is also optimised for
architectures having a fast unaligned access.
Signed-off-by: Antonio Quartulli <a@unstable.cc>
[sven@narfation.org: fix conflicts with current version]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
It is easier to understand that the returned value of a specific function
doesn't have to be 0 when the functions was successful when the actual
return type is bool. This is especially true when all surrounding functions
with return type int use negative values to return the error code.
Reported-by: Nicholas Krause <xerofoify@gmail.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
batadv_nc_get_nc_node requires that the caller already has a valid
reference for orig_neigh_node. It is therefore not possible that it has an
reference counter of 0 and was still given to this function
The kref_get function instead WARNs (with debug information) when the
reference counter would still be 0. This makes a bug in batman-adv better
visible because kref_get_unless_zero would have ignored this problem.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Some really long function names in batman-adv require a newline between
return type and the function name. This has lead to some lines starting
with *batadv_...
This * belongs to the return type and thus should be on the same line as
the return type.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Use to_delayed_work() instead of open-coding it.
Signed-off-by: Geliang Tang <geliangtang@163.com>
Reviewed-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
To enable ELP to send probing packets over wireless links
only if needed, batman-adv must keep track of the last time
it sent a unicast packet towards every neighbour.
For this purpose a 2 main changes are introduced:
1) a new member of the elp_neigh_node structure stores the
last time a unicast packet was sent towards this neighbour;
2) a wrapper function for sending unicast packets is
implemented. This function will simply update the member
describe din point 1) and then forward the packet to the
real sending routine.
Point 2) implies that any code-path leading to a unicast
sending now has to use the new wrapper.
Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
The batman-adv source code is the only place in the kernel which uses the
*_free_ref naming scheme for the *_put functions. Changing it to *_put
makes it more consistent and makes it easier to understand the connection
to the *_get functions.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
The batman-adv source code is the only place in the kernel which uses the
*_free_ref naming scheme for the *_put functions. Changing it to *_put
makes it more consistent and makes it easier to understand the connection
to the *_get functions.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
The batman-adv source code is the only place in the kernel which uses the
*_free_ref naming scheme for the *_put functions. Changing it to *_put
makes it more consistent and makes it easier to understand the connection
to the *_get functions.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
The batman-adv source code is the only place in the kernel which uses the
*_free_ref naming scheme for the *_put functions. Changing it to *_put
makes it more consistent and makes it easier to understand the connection
to the *_get functions.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
The batman-adv source code is the only place in the kernel which uses the
*_free_ref naming scheme for the *_put functions. Changing it to *_put
makes it more consistent and makes it easier to understand the connection
to the *_get functions.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
The batman-adv source code is the only place in the kernel which uses the
*_free_ref naming scheme for the *_put functions. Changing it to *_put
makes it more consistent and makes it easier to understand the connection
to the *_get functions.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
The batman-adv source code is the only place in the kernel which uses the
*_free_ref naming scheme for the *_put functions. Changing it to *_put
makes it more consistent and makes it easier to understand the connection
to the *_get functions.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
batman-adv uses a self-written reference implementation which is just based
on atomic_t. This is less obvious when reading the code than kref and
therefore increases the change that the reference counting will be missed.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
batman-adv uses a self-written reference implementation which is just based
on atomic_t. This is less obvious when reading the code than kref and
therefore increases the change that the reference counting will be missed.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
batman-adv uses a self-written reference implementation which is just based
on atomic_t. This is less obvious when reading the code than kref and
therefore increases the change that the reference counting will be missed.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Pavel Skripkin