mirror of https://gitee.com/openkylin/linux.git
ecca8f88da
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> |
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| .. | ||
| Kconfig | ||
| Makefile | ||
| associola.c | ||
| auth.c | ||
| bind_addr.c | ||
| chunk.c | ||
| debug.c | ||
| endpointola.c | ||
| input.c | ||
| inqueue.c | ||
| ipv6.c | ||
| objcnt.c | ||
| offload.c | ||
| output.c | ||
| outqueue.c | ||
| primitive.c | ||
| probe.c | ||
| proc.c | ||
| protocol.c | ||
| sctp_diag.c | ||
| sm_make_chunk.c | ||
| sm_sideeffect.c | ||
| sm_statefuns.c | ||
| sm_statetable.c | ||
| socket.c | ||
| stream.c | ||
| stream_sched.c | ||
| stream_sched_prio.c | ||
| stream_sched_rr.c | ||
| sysctl.c | ||
| transport.c | ||
| tsnmap.c | ||
| ulpevent.c | ||
| ulpqueue.c | ||