Marc Dionne c4c613ff08 afs: Fix possible oops in afs_lookup trace event
The afs_lookup trace event can cause the following:

[  216.576777] BUG: kernel NULL pointer dereference, address: 000000000000023b
[  216.576803] #PF: supervisor read access in kernel mode
[  216.576813] #PF: error_code(0x0000) - not-present page
...
[  216.576913] RIP: 0010:trace_event_raw_event_afs_lookup+0x9e/0x1c0 [kafs]

If the inode from afs_do_lookup() is an error other than ENOENT, or if it
is ENOENT and afs_try_auto_mntpt() returns an error, the trace event will
try to dereference the error pointer as a valid pointer.

Use IS_ERR_OR_NULL to only pass a valid pointer for the trace, or NULL.

Ideally the trace would include the error value, but for now just avoid
the oops.

Fixes: 80548b03991f ("afs: Add more tracepoints")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-08-22 13:33:26 +01:00
..
2019-08-18 09:51:48 -07:00
2019-07-12 17:37:53 -07:00
2019-07-12 16:54:37 -07:00
2019-07-30 13:15:39 -07:00
2019-08-09 16:56:12 +01:00
2019-07-25 11:05:11 +02:00
2019-07-03 17:52:09 -04:00
2019-06-21 09:58:42 -07:00
\n
2019-07-10 20:27:07 -07:00
\n
2019-07-10 20:09:17 -07:00
\n
2019-07-10 20:27:07 -07:00
2019-08-15 11:09:16 -06:00
2019-07-15 21:20:52 -07:00
2019-05-21 08:23:41 +01:00
2019-04-08 18:21:02 -05:00
2019-03-08 14:48:40 -08:00
2019-07-12 16:54:37 -07:00
2019-07-10 21:22:43 -07:00
2019-02-07 16:38:35 +01:00
2019-07-31 12:22:32 -04:00