diff options
author | Roland Dreier <rolandd@cisco.com> | 2006-11-13 09:38:07 -0800 |
---|---|---|
committer | Roland Dreier <rolandd@cisco.com> | 2006-11-13 09:38:07 -0800 |
commit | 39798695b4bcc7b145f8910ca56195808d3a7637 (patch) | |
tree | 89f594faf977f800893f6fa59213e94e098df386 | |
parent | b26c791e9ca3365616d40836000285931ca033d0 (diff) |
IB/mad: Fix race between cancel and receive completion
When ib_cancel_mad() is called, it puts the canceled send on a list
and schedules a "flushed" callback from process context. However,
this leaves a window where a receive completion could be processed
before the send is fully flushed.
This is fine, except that ib_find_send_mad() will find the MAD and
return it to the receive processing, which results in the sender
getting both a successful receive and a "flushed" send completion for
the same request. Understandably, this confuses the sender, which is
expecting only one of these two callbacks, and leads to grief such as
a use-after-free in IPoIB.
Fix this by changing ib_find_send_mad() to return a send struct only
if the status is still successful (and not "flushed"). The search of
the send_list already had this check, so this patch just adds the same
check to the search of the wait_list.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
-rw-r--r-- | drivers/infiniband/core/mad.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/infiniband/core/mad.c b/drivers/infiniband/core/mad.c index 493f4c65c7a2..a72bcea46ff6 100644 --- a/drivers/infiniband/core/mad.c +++ b/drivers/infiniband/core/mad.c @@ -1750,7 +1750,7 @@ ib_find_send_mad(struct ib_mad_agent_private *mad_agent_priv, */ (is_direct(wc->recv_buf.mad->mad_hdr.mgmt_class) || rcv_has_same_gid(mad_agent_priv, wr, wc))) - return wr; + return (wr->status == IB_WC_SUCCESS) ? wr : NULL; } /* |