4.8-stable review patch. If anyone has any objections, please let me know.
------------------ From: Eric W. Biederman <[email protected]> commit 069d5ac9ae0d271903cc4607890616418118379a upstream. Seth Forshee reports that in 4.8-rcN some automounts are failing because the requesting the automount changed. The relevant call path is: follow_automount() ->d_automount autofs4_d_automount autofs4_mount_wait autofs4_wait In autofs4_wait wq_uid and wq_gid are set to current_uid() and current_gid respectively. With follow_automount now overriding creds uid that we export to userspace changes and that breaks existing setups. To remove the regression set wq_uid and wq_gid from current_real_cred()->uid and current_real_cred()->gid respectively. This restores the current behavior as current->real_cred is identical to current->cred except when override creds are used. Fixes: aeaa4a79ff6a ("fs: Call d_automount with the filesystems creds") Reported-by: Seth Forshee <[email protected]> Tested-by: Seth Forshee <[email protected]> Signed-off-by: "Eric W. Biederman" <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- fs/autofs4/waitq.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/fs/autofs4/waitq.c +++ b/fs/autofs4/waitq.c @@ -431,8 +431,8 @@ int autofs4_wait(struct autofs_sb_info * memcpy(&wq->name, &qstr, sizeof(struct qstr)); wq->dev = autofs4_get_dev(sbi); wq->ino = autofs4_get_ino(sbi); - wq->uid = current_uid(); - wq->gid = current_gid(); + wq->uid = current_real_cred()->uid; + wq->gid = current_real_cred()->gid; wq->pid = pid; wq->tgid = tgid; wq->status = -EINTR; /* Status return if interrupted */
