IB/srp: Fix a sporadic crash triggered by cable pulling
authorBart Van Assche <bvanassche@acm.org>
Tue, 20 May 2014 13:03:49 +0000 (15:03 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 7 Jul 2014 01:54:14 +0000 (18:54 -0700)
commit364461b2890b3f763872a5d05139430b5c67da94
tree5ad864a7d61ae5d5e269ac1d9608bb5d0406da1a
parenta533eba6682f1dc89bfa5dc6e16e18ea257dd4d0
IB/srp: Fix a sporadic crash triggered by cable pulling

commit 024ca90151f5e4296d30f72c13ff9a075e23c9ec upstream.

Avoid that the loops that iterate over the request ring can encounter
a pointer to a SCSI command in req->scmnd that is no longer associated
with that request. If the function srp_unmap_data() is invoked twice
for a SCSI command that is not in flight then that would cause
ib_fmr_pool_unmap() to be invoked with an invalid pointer as argument,
resulting in a kernel oops.

Reported-by: Sagi Grimberg <sagig@mellanox.com>
Reference: http://thread.gmane.org/gmane.linux.drivers.rdma/19068/focus=19069
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/infiniband/ulp/srp/ib_srp.c