On Thu, Oct 01, 2020 at 08:50:55AM -0400, Qian Cai wrote:
> Calling pipe2() with O_NOTIFICATION_PIPE could results in memory leaks
> in an error path or CONFIG_WATCH_QUEUE=n. Plug them.
[snip the copy of bug report]
No objections on the patch itself, but commit message is just about
unreadable. How about something along the lines of the following?
=======================
Calling pipe2() with O_NOTIFICATION_PIPE could results in memory
leaks unless watch_queue_init() is successful.
In case of watch_queue_init() failure in pipe2() we are left
with inode and pipe_inode_info instances that need to be freed. That
failure exit has been introduced in commit c73be61cede5 ("pipe: Add
general notification queue support") and its handling should've been
identical to nearby treatment of alloc_file_pseudo() failures - it
is dealing with the same situation. As it is, the mainline kernel
leaks in that case.
Another problem is that CONFIG_WATCH_QUEUE and !CONFIG_WATCH_QUEUE
cases are treated differently (and the former leaks just pipe_inode_info,
the latter - both pipe_inode_info and inode).
Fixed by providing a dummy wath_queue_init() in !CONFIG_WATCH_QUEUE
case and by having failures of wath_queue_init() handled the same way
we handle alloc_file_pseudo() ones.
Fixes: c73be61cede5 ("pipe: Add general notification queue support")
Signed-off-by: Qian Cai <cai@xxxxxxxxxx>
=======================
