diff options
| author | Hariprasad S <hariprasad@chelsio.com> | 2016-05-04 22:57:31 +0300 |
|---|---|---|
| committer | Doug Ledford <dledford@redhat.com> | 2016-05-05 23:11:14 +0300 |
| commit | 6e410d8f7175caf2316c515f1ea0bf80d33b3158 (patch) | |
| tree | 06f9d18b62083f5cd0638daf72530b549b1b44a7 /drivers/infiniband | |
| parent | 88bc230dc614b8e19000022d0ae2c1dfd578a0b0 (diff) | |
| download | linux-6e410d8f7175caf2316c515f1ea0bf80d33b3158.tar.xz | |
RDMA/iw_cxgb4: ensure eps don't get freed while the mutex is held
In rx_data(), with the ep in FPDU_MODE, refcnt=2, if we get unexpected
streaming data, we call c4iw_modify_rc_qp() and move the qp from
RTS -> TERMINATE. In c4iw_modify_rc_qp(), if rdma_fini() returns
an error, the ep will be dereferenced (refcnt=1). Then rx_data()
calls c4iw_ep_disconnect() which starts the close operation.
But if send_halfclose() fails in c4iw_ep_disconnect(), we will call
release_ep_resources() derefing the ep which reduces the refcnt to 0 and
and frees the ep. However we still has the ep mutex at that point, so we
have a touch-after-free bug. There is a similar issue where
peer_close() calls c4iw_ep_disconnect().
The solution is to add a reference to the ep in c4iw_ep_disconnect()
after acquiring the mutex, and release it after releasing the mutex.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Diffstat (limited to 'drivers/infiniband')
| -rw-r--r-- | drivers/infiniband/hw/cxgb4/cm.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/cxgb4/cm.c b/drivers/infiniband/hw/cxgb4/cm.c index cc9836e46800..12eac98661c1 100644 --- a/drivers/infiniband/hw/cxgb4/cm.c +++ b/drivers/infiniband/hw/cxgb4/cm.c @@ -3416,6 +3416,12 @@ int c4iw_ep_disconnect(struct c4iw_ep *ep, int abrupt, gfp_t gfp) PDBG("%s ep %p state %s, abrupt %d\n", __func__, ep, states[ep->com.state], abrupt); + /* + * Ref the ep here in case we have fatal errors causing the + * ep to be released and freed. + */ + c4iw_get_ep(&ep->com); + rdev = &ep->com.dev->rdev; if (c4iw_fatal_error(rdev)) { fatal = 1; @@ -3476,6 +3482,7 @@ int c4iw_ep_disconnect(struct c4iw_ep *ep, int abrupt, gfp_t gfp) } } mutex_unlock(&ep->com.mutex); + c4iw_put_ep(&ep->com); if (fatal) release_ep_resources(ep); return ret; |