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@xxxxxxxxxxxx> Reference: http://thread.gmane.org/gmane.linux.drivers.rdma/19068/focus=19069 Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx> Cc: Roland Dreier <roland@xxxxxxxxxxxxxxx> Cc: David Dillow <dave@xxxxxxxxxxxxxx> Cc: Sagi Grimberg <sagig@xxxxxxxxxxxx> Cc: Vu Pham <vu@xxxxxxxxxxxx> Cc: Sebastian Parschauer <sebastian.riemer@xxxxxxxxxxxxxxxx> Cc: stable <stable@xxxxxxxxxxxxxxx> --- drivers/infiniband/ulp/srp/ib_srp.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c index 66a908b..5b2bed8 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); -- 1.8.4.5 -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
