diff options
author | Bart Van Assche <bart.vanassche@sandisk.com> | 2017-02-14 10:56:30 -0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-03-15 09:57:13 +0800 |
commit | 944690cdb5f48d03842365b7359fe090d6c2b1fa (patch) | |
tree | 1900f3bffd82a54bfaeb813143074068a44ca1b9 | |
parent | bb4a21dcb6fb57892eea7c941fdfd57e55ba5dbe (diff) |
IB/srp: Avoid that duplicate responses trigger a kernel bug
commit 6cb72bc1b40bb2c1750ee7a5ebade93bed49a5fb upstream.
After srp_process_rsp() returns there is a short time during which
the scsi_host_find_tag() call will return a pointer to the SCSI
command that is being completed. If during that time a duplicate
response is received, avoid that the following call stack appears:
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: srp_recv_done+0x450/0x6b0 [ib_srp]
Oops: 0000 [#1] SMP
CPU: 10 PID: 0 Comm: swapper/10 Not tainted 4.10.0-rc7-dbg+ #1
Call Trace:
<IRQ>
__ib_process_cq+0x4b/0xd0 [ib_core]
ib_poll_handler+0x1d/0x70 [ib_core]
irq_poll_softirq+0xba/0x120
__do_softirq+0xba/0x4c0
irq_exit+0xbe/0xd0
smp_apic_timer_interrupt+0x38/0x50
apic_timer_interrupt+0x90/0xa0
</IRQ>
RIP: srp_recv_done+0x450/0x6b0 [ib_srp] RSP: ffff88046f483e20
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Israel Rukshin <israelr@mellanox.com>
Cc: Max Gurtovoy <maxg@mellanox.com>
Cc: Laurence Oberman <loberman@redhat.com>
Cc: Steve Feeley <Steve.Feeley@sandisk.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/infiniband/ulp/srp/ib_srp.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c index 5f0f4fc58f43..57a8a200e741 100644 --- a/drivers/infiniband/ulp/srp/ib_srp.c +++ b/drivers/infiniband/ulp/srp/ib_srp.c @@ -1795,9 +1795,11 @@ static void srp_process_rsp(struct srp_rdma_ch *ch, struct srp_rsp *rsp) complete(&ch->tsk_mgmt_done); } else { scmnd = scsi_host_find_tag(target->scsi_host, rsp->tag); - if (scmnd) { + if (scmnd && scmnd->host_scribble) { req = (void *)scmnd->host_scribble; scmnd = srp_claim_req(ch, req, NULL, scmnd); + } else { + scmnd = NULL; } if (!scmnd) { shost_printk(KERN_ERR, target->scsi_host, |