From d9a9f4849fe0c9d560851ab22a85a666cddfdd24 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 12 Mar 2020 18:25:20 -0400 Subject: cifs_atomic_open(): fix double-put on late allocation failure several iterations of ->atomic_open() calling conventions ago, we used to need fput() if ->atomic_open() failed at some point after successful finish_open(). Now (since 2016) it's not needed - struct file carries enough state to make fput() work regardless of the point in struct file lifecycle and discarding it on failure exits in open() got unified. Unfortunately, I'd missed the fact that we had an instance of ->atomic_open() (cifs one) that used to need that fput(), as well as the stale comment in finish_open() demanding such late failure handling. Trivially fixed... Fixes: fe9ec8291fca "do_last(): take fput() on error after opening to out:" Cc: stable@kernel.org # v4.7+ Signed-off-by: Al Viro --- Documentation/filesystems/porting.rst | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'Documentation') diff --git a/Documentation/filesystems/porting.rst b/Documentation/filesystems/porting.rst index f18506083ced..26c093969573 100644 --- a/Documentation/filesystems/porting.rst +++ b/Documentation/filesystems/porting.rst @@ -850,3 +850,11 @@ business doing so. d_alloc_pseudo() is internal-only; uses outside of alloc_file_pseudo() are very suspect (and won't work in modules). Such uses are very likely to be misspelled d_alloc_anon(). + +--- + +**mandatory** + +[should've been added in 2016] stale comment in finish_open() nonwithstanding, +failure exits in ->atomic_open() instances should *NOT* fput() the file, +no matter what. Everything is handled by the caller. -- cgit v1.2.3-59-g8ed1b