Created attachment 1065676 [details]
patch to correct broken uid/gid and fix pid/tgid lines

Description of problem:

commit 52e9e2ef9fcf667da3b09de834fd4b7566c773d8 for bugzilla 858164 broke autofs uid and gid, and did not solve bugzilla 858164 correctly.

In addition, Customer experienced autofs mount failures when mounting cifs volumes using krb authentication


Version-Release number of selected component (if applicable):

kernels 2.6.32-505.el6-7-g52e9e2e and more recent


How reproducible:

always

Steps to Reproduce:

 Code review

 Automount failure was reproduced by customer, but not provided.


Actual results:

 mount is attempted with uid=0 and gid=0


Expected results:

 mount is attempted with uid/gid of the user making the call 


Additional info:

 This is a regression from the RHEL 6.6 kernel.

 Verbose automount debugging from 2.6.32-504.30.3.el6 kernel shows correct uid/gid in mount attempt:

2015-08-13T14:38:02.950816+02:00 server1 automount[2864]: mount_mount: mount(generic): calling mount -t cifs -s -o sec=krb5,uid=500,gid=100,file_mode=0700,dir_mode=0700,nobrl //server2/scanner /mnt/server2_scanner

 in 2.6.32-573.3.1.el6 kernel, uid/gid 0 are used in mount attempt:
2015-08-13T14:23:31.750570+02:00 server1 automount[5128]: mount_mount: mount(generic): calling mount -t cifs -s -o sec=krb5,uid=0,gid=0,file_mode=0700,dir_mode=0700,nobrl //server2/scanner /mnt/server2_scanner


The broken commit replaced the 'wq->uid' and 'wq->gid' lines, rather than the 'wq->pid' and 'wq->tgid' lines:

diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c
index 150826b..ded41e6 100644
--- a/fs/autofs4/waitq.c
+++ b/fs/autofs4/waitq.c
@@ -410,8 +422,8 @@ int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,
                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->pid = pid;
+               wq->tgid = tgid;
                wq->pid = current->pid;
                wq->tgid = current->tgid;
                wq->status = -EINTR; /* Status return if interrupted */


patch to correct this is attached