diff options
author | David Jeffery <djeffery@redhat.com> | 2013-07-10 13:19:50 -0400 |
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committer | J. Bruce Fields <bfields@redhat.com> | 2013-07-11 17:24:07 -0400 |
commit | 1c327d962fc420aea046c16215a552710bde8231 (patch) | |
tree | 2ab025c8b577d7fe338b1530bea72c3fa0ef0d72 /net/netfilter/xt_realm.c | |
parent | d109148111cdfcdae94f797dc142468bd0ff7557 (diff) |
lockd: protect nlm_blocked access in nlmsvc_retry_blocked
In nlmsvc_retry_blocked, the check that the list is non-empty and acquiring
the pointer of the first entry is unprotected by any lock. This allows a rare
race condition when there is only one entry on the list. A function such as
nlmsvc_grant_callback() can be called, which will temporarily remove the entry
from the list. Between the list_empty() and list_entry(),the list may become
empty, causing an invalid pointer to be used as an nlm_block, leading to a
possible crash.
This patch adds the nlm_block_lock around these calls to prevent concurrent
use of the nlm_blocked list.
This was a regression introduced by
f904be9cc77f361d37d71468b13ff3d1a1823dea "lockd: Mostly remove BKL from
the server".
Cc: Bryan Schumaker <bjschuma@netapp.com>
Cc: stable@vger.kernel.org
Signed-off-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'net/netfilter/xt_realm.c')
0 files changed, 0 insertions, 0 deletions