Commit Graph

14 Commits

Author SHA1 Message Date
Randy Dunlap 201a08830d net: llc: fix kernel-doc notation warnings
Use the corrent function parameter name or format to prevent
kernel-doc warnings.
Add 2 function parameter descriptions to prevent kernel-doc warnings.

llc_pdu.h:278: warning: Function parameter or member 'da' not described in 'llc_pdu_decode_da'
llc_pdu.h:278: warning: Excess function parameter 'sa' description in 'llc_pdu_decode_da'
llc_pdu.h:330: warning: Function parameter or member 'skb' not described in 'llc_pdu_init_as_test_cmd'
llc_pdu.h:379: warning: Function parameter or member 'svcs_supported' not described in 'llc_pdu_init_as_xid_cmd'
llc_pdu.h:379: warning: Function parameter or member 'rx_window' not described in 'llc_pdu_init_as_xid_cmd'

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20230714045127.18752-7-rdunlap@infradead.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-07-14 20:39:29 -07:00
Pavel Skripkin c7c9d2102c net: llc: fix skb_over_panic
Syzbot reported skb_over_panic() in llc_pdu_init_as_xid_cmd(). The
problem was in wrong LCC header manipulations.

Syzbot's reproducer tries to send XID packet. llc_ui_sendmsg() is
doing following steps:

	1. skb allocation with size = len + header size
		len is passed from userpace and header size
		is 3 since addr->sllc_xid is set.

	2. skb_reserve() for header_len = 3
	3. filling all other space with memcpy_from_msg()

Ok, at this moment we have fully loaded skb, only headers needs to be
filled.

Then code comes to llc_sap_action_send_xid_c(). This function pushes 3
bytes for LLC PDU header and initializes it. Then comes
llc_pdu_init_as_xid_cmd(). It initalizes next 3 bytes *AFTER* LLC PDU
header and call skb_push(skb, 3). This looks wrong for 2 reasons:

	1. Bytes rigth after LLC header are user data, so this function
	   was overwriting payload.

	2. skb_push(skb, 3) call can cause skb_over_panic() since
	   all free space was filled in llc_ui_sendmsg(). (This can
	   happen is user passed 686 len: 686 + 14 (eth header) + 3 (LLC
	   header) = 703. SKB_DATA_ALIGN(703) = 704)

So, in this patch I added 2 new private constansts: LLC_PDU_TYPE_U_XID
and LLC_PDU_LEN_U_XID. LLC_PDU_LEN_U_XID is used to correctly reserve
header size to handle LLC + XID case. LLC_PDU_TYPE_U_XID is used by
llc_pdu_header_init() function to push 6 bytes instead of 3. And finally
I removed skb_push() call from llc_pdu_init_as_xid_cmd().

This changes should not affect other parts of LLC, since after
all steps we just transmit buffer.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-and-tested-by: syzbot+5e5a981ad7cc54c4b2b4@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-27 13:05:56 +01:00
Daniel Borkmann 7e0309631e net: llc: fix order of evaluation in llc_conn_ac_inc_vr_by_1
Function llc_conn_ac_inc_vr_by_1() evaluates via macro
PDU_GET_NEXT_Vr() into ...

  llc_sk(sk)->vR = ++llc_sk(sk)->vR & 0xffffffffffffff7f

... but the order in which the side effects take place is
undefined because there is no intervening sequence point.

As llc_sk(sk)->vR is written in llc_sk(sk)->vR (assignment
left-hand side) and written in ++llc_sk(sk)->vR & 0xffffffffffffff7f
this might possibly yield undefined behavior.

The final value of llc_sk(sk)->vR is ambiguous, because,
depending on the order of expression evaluation, the
increment may occur before, after, or interleaved with
the assignment. In C, evaluating such an expression yields
undefined behavior.

Since we're doing the increment via PDU_GET_NEXT_Vr() macro
and the only place it is being used is from
llc_conn_ac_inc_vr_by_1(), in order to increment vR by 1
with a follow-up optimized modulo, rewrite the expression
into ((vR + 1) & CONST) in order to fix this.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-01 22:22:43 -05:00
Joe Perches bf3c710f71 llc*.h: Remove extern from function prototypes
There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-21 14:01:38 -04:00
Paul Gortmaker 211ed86510 net: delete all instances of special processing for token ring
We are going to delete the Token ring support.  This removes any
special processing in the core networking for token ring, (aside
from net/tr.c itself), leaving the drivers and remaining tokenring
support present but inert.

The mass removal of the drivers and net/tr.c will be in a separate
commit, so that the history of these files that we still care
about won't have the giant deletion tied into their history.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-05-15 20:14:35 -04:00
Vitalii Demianets a10e146676 bonding,llc: Fix structure sizeof incompatibility for some PDUs
With some combinations of arch/compiler (e.g. arm-linux-gcc) the sizeof
operator on structure returns value greater than expected. In cases when the
structure is used for mapping PDU fields it may lead to unexpected results
(such as holes and alignment problems in skb data). __packed prevents this
undesired behavior.

Signed-off-by: Vitalii Demianets <vitas@nppfactor.kiev.ua>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-13 15:13:24 -04:00
Joonwoo Park f83f1768f8 [LLC]: skb allocation size for responses
Allocate the skb for llc responses with the received packet size by
using the size adjustable llc_frame_alloc.
Don't allocate useless extra payload.
Cleanup magic numbers.

So, this fixes oops.
Reported by Jim Westfall:
kernel: skb_over_panic: text:c0541fc7 len:1000 put:997 head:c166ac00 data:c166ac2f tail:0xc166b017 end:0xc166ac80 dev:eth0
kernel: ------------[ cut here ]------------
kernel: kernel BUG at net/core/skbuff.c:95!

Signed-off-by: Joonwoo Park <joonwpark81@gmail.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-31 21:02:47 -07:00
Arnaldo Carvalho de Melo d56f90a7c9 [SK_BUFF]: Introduce skb_network_header()
For the places where we need a pointer to the network header, it is still legal
to touch skb->nh.raw directly if just adding to, subtracting from or setting it
to another layer header.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:24:59 -07:00
Arnaldo Carvalho de Melo c1d2bbe1cd [SK_BUFF]: Introduce skb_reset_network_header(skb)
For the common, open coded 'skb->nh.raw = skb->data' operation, so that we can
later turn skb->nh.raw into a offset, reducing the size of struct sk_buff in
64bit land while possibly keeping it as a pointer on 32bit.

This one touches just the most simple case, next will handle the slightly more
"complex" cases.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:24:46 -07:00
Arnaldo Carvalho de Melo 37e6636669 [LLC]: Kill llc_set_pdu_hdr
We'll have skb_reset_network_header soon.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:24:42 -07:00
Al Viro 3fbd418acc [LLC]: anotations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:21:23 -08:00
Jochen Friedrich cf22535657 [LLC]: Fix typo
Signed-off-by: Jochen Friedrich <jochen@scram.de>
Acked-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-11-14 21:58:18 -08:00
Jochen Friedrich 5ed688a716 [LLC]: Strip RIF flag from source MAC address
Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-10-25 21:34:39 -02:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00