Re: WARNING in rds_cmsg_rdma_args

From: Santosh Shilimkar
Date: Wed Jan 03 2018 - 13:43:29 EST


On 1/3/2018 12:58 AM, syzbot wrote:
Hello,

syzkaller hit the following crash on ad036b63ee57df9ab802a4eb20cbbbec66aa4520
git://git.cmpxchg.org/linux-mmots.git/master
compiler: gcc (GCC) 7.1.1 20170620
.config is attached
Raw console output is attached.
C reproducer is attached
syzkaller reproducer is attached. See


for information about syzkaller reproducers


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audit: type=1400 audit(1514947982.760:7): avc: denied { map } for pid=3468 comm="syzkaller284818" path="/root/syzkaller284818499" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1
WARNING: CPU: 1 PID: 3468 at net/rds/rdma.c:617 rds_cmsg_rdma_args+0xe96/0x1360 net/rds/rdma.c:617
Kernel panic - not syncing: panic_on_warn set ...

+Mohamed Ghannam, who was discussing similar issue and was going
to post fix for it. Checking args->nr_local against 0 upfront would
address this issue as well.

Regards,
Santosh