Re: [PATCH] kcm: fix /proc memory leak

From: David Miller
Date: Wed Jun 22 2016 - 16:33:21 EST


From: Jiri Slaby <jslaby@xxxxxxx>
Date: Mon, 20 Jun 2016 11:36:28 +0200

> Every open of /proc/net/kcm leaks 16 bytes of memory as is reported by
> kmemleak:
> unreferenced object 0xffff88059c0e3458 (size 192):
> comm "cat", pid 1401, jiffies 4294935742 (age 310.720s)
> hex dump (first 32 bytes):
> 28 45 71 96 05 88 ff ff 00 10 00 00 00 00 00 00 (Eq.............
> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
> backtrace:
> [<ffffffff8156a2de>] kmem_cache_alloc_trace+0x16e/0x230
> [<ffffffff8162a479>] seq_open+0x79/0x1d0
> [<ffffffffa0578510>] kcm_seq_open+0x0/0x30 [kcm]
> [<ffffffff8162a479>] seq_open+0x79/0x1d0
> [<ffffffff8162a8cf>] __seq_open_private+0x2f/0xa0
> [<ffffffff81712548>] seq_open_net+0x38/0xa0
> ...
>
> It is caused by a missing free in the ->release path. So fix it by
> providing seq_release_net as the ->release method.
>
> Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
> Fixes: cd6e111bf5 (kcm: Add statistics and proc interfaces)

Applied and queued up for -stable, thanks.