提交 50c6e282 编写于 作者: C Christoph Hellwig 提交者: Al Viro

posix_acl: handle NULL ACL in posix_acl_equiv_mode

Various filesystems don't bother checking for a NULL ACL in
posix_acl_equiv_mode, and thus can dereference a NULL pointer when it
gets passed one. This usually happens from the NFS server, as the ACL tools
never pass a NULL ACL, but instead of one representing the mode bits.

Instead of adding boilerplat to all filesystems put this check into one place,
which will allow us to remove the check from other filesystems as well later
on.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reported-by: NBen Greear <greearb@candelatech.com>
Reported-by: Marco Munderloh <munderl@tnt.uni-hannover.de>,
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
上级 60942f2f
...@@ -246,6 +246,12 @@ posix_acl_equiv_mode(const struct posix_acl *acl, umode_t *mode_p) ...@@ -246,6 +246,12 @@ posix_acl_equiv_mode(const struct posix_acl *acl, umode_t *mode_p)
umode_t mode = 0; umode_t mode = 0;
int not_equiv = 0; int not_equiv = 0;
/*
* A null ACL can always be presented as mode bits.
*/
if (!acl)
return 0;
FOREACH_ACL_ENTRY(pa, acl, pe) { FOREACH_ACL_ENTRY(pa, acl, pe) {
switch (pa->e_tag) { switch (pa->e_tag) {
case ACL_USER_OBJ: case ACL_USER_OBJ:
......
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册