linux_dsm_epyc7002/include/net/sctp
Xin Long ecca8f88da sctp: set frag_point in sctp_setsockopt_maxseg correctly
Now in sctp_setsockopt_maxseg user_frag or frag_point can be set with
val >= 8 and val <= SCTP_MAX_CHUNK_LEN. But both checks are incorrect.

val >= 8 means frag_point can even be less than SCTP_DEFAULT_MINSEGMENT.
Then in sctp_datamsg_from_user(), when it's value is greater than cookie
echo len and trying to bundle with cookie echo chunk, the first_len will
overflow.

The worse case is when it's value is equal as cookie echo len, first_len
becomes 0, it will go into a dead loop for fragment later on. In Hangbin
syzkaller testing env, oom was even triggered due to consecutive memory
allocation in that loop.

Besides, SCTP_MAX_CHUNK_LEN is the max size of the whole chunk, it should
deduct the data header for frag_point or user_frag check.

This patch does a proper check with SCTP_DEFAULT_MINSEGMENT subtracting
the sctphdr and datahdr, SCTP_MAX_CHUNK_LEN subtracting datahdr when
setting frag_point via sockopt. It also improves sctp_setsockopt_maxseg
codes.

Suggested-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Reported-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-18 10:32:41 +09:00
..
auth.h net, sctp: convert sctp_auth_bytes.refcnt from atomic_t to refcount_t 2017-07-04 22:35:18 +01:00
checksum.h include/net/: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
command.h sctp: remove the typedef sctp_verb_t 2017-08-11 10:02:44 -07:00
constants.h sctp: remove the typedef sctp_subtype_t 2017-08-06 21:33:42 -07:00
sctp.h sctp: set frag_point in sctp_setsockopt_maxseg correctly 2017-11-18 10:32:41 +09:00
sm.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-10-30 21:09:24 +09:00
stream_sched.h sctp: introduce stream scheduler foundations 2017-10-03 16:27:29 -07:00
structs.h sctp: introduce round robin stream scheduler 2017-10-03 16:27:29 -07:00
tsnmap.h sctp: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
ulpevent.h sctp: fix some type cast warnings introduced by stream reconf 2017-10-29 18:03:24 +09:00
ulpqueue.h sctp: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00