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authorBart Van Assche <bvanassche@acm.org>2014-05-20 15:03:49 +0200
committerRoland Dreier <roland@purestorage.com>2014-05-20 09:20:51 -0700
commit024ca90151f5e4296d30f72c13ff9a075e23c9ec (patch)
treefe418c63a06d19c3739c58ff988ccf6b95d0d100
parentd6d211db37e75de2ddc3a4f979038c40df7cc79c (diff)
IB/srp: Fix a sporadic crash triggered by cable pulling
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> Cc: stable <stable@vger.kernel.org> Signed-off-by: Roland Dreier <roland@purestorage.com>
-rw-r--r--drivers/infiniband/ulp/srp/ib_srp.c6
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c
index 66a908bf3fb..5b2bed8fc49 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -1594,6 +1594,12 @@ err_unmap:
err_iu:
srp_put_tx_iu(target, iu, SRP_IU_CMD);
+ /*
+ * Avoid that the loops that iterate over the request ring can
+ * encounter a dangling SCSI command pointer.
+ */
+ req->scmnd = NULL;
+
spin_lock_irqsave(&target->lock, flags);
list_add(&req->list, &target->free_reqs);