From: Eric W. Biederman Date: Fri, 30 Sep 2016 16:28:05 +0000 (-0500) Subject: autofs: Fix automounts by using current_real_cred()->uid X-Git-Tag: v4.9-rc1~111^2 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=069d5ac9ae0d271903cc4607890616418118379a;p=linux.git autofs: Fix automounts by using current_real_cred()->uid 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. Cc: stable@vger.kernel.org Fixes: aeaa4a79ff6a ("fs: Call d_automount with the filesystems creds") Reported-by: Seth Forshee Tested-by: Seth Forshee Signed-off-by: "Eric W. Biederman" --- diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c index 431fd7ee3488..e44271dfceb6 100644 --- a/fs/autofs4/waitq.c +++ b/fs/autofs4/waitq.c @@ -431,8 +431,8 @@ int autofs4_wait(struct autofs_sb_info *sbi, 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 */