[PATCH 4.1 60/86] ovl: free lower_mnt array in ovl_put_super

Greg Kroah-Hartman
2015-11-06T20:05:04Z

From: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>

commit 5ffdbe8bf1e485026e1c7e4714d2841553cf0b40 upstream.

This fixes memory leak after umount.

Kmemleak report:

unreferenced object 0xffff8800ba791010 (size 8):
comm "mount", pid 2394, jiffies 4294996294 (age 53.920s)
hex dump (first 8 bytes):
20 1c 13 02 00 88 ff ff .......
backtrace:
[<ffffffff811f8cd4>] create_object+0x124/0x2c0
[<ffffffff817a059b>] kmemleak_alloc+0x7b/0xc0
[<ffffffff811dffe6>] __kmalloc+0x106/0x340
[<ffffffffa0152bfc>] ovl_fill_super+0x55c/0x9b0 [overlay]
[<ffffffff81200ac4>] mount_nodev+0x54/0xa0
[<ffffffffa0152118>] ovl_mount+0x18/0x20 [overlay]
[<ffffffff81201ab3>] mount_fs+0x43/0x170
[<ffffffff81220d34>] vfs_kern_mount+0x74/0x170
[<ffffffff812233ad>] do_mount+0x22d/0xdf0
[<ffffffff812242cb>] SyS_mount+0x7b/0xc0
[<ffffffff817b6bee>] entry_SYSCALL_64_fastpath+0x12/0x76
[<ffffffffffffffff>] 0xffffffffffffffff

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Fixes: dd662667e6d3 ("ovl: add mutli-layer infrastructure")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/overlayfs/super.c | 1 +
1 file changed, 1 insertion(+)

--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -474,6 +474,7 @@ static void ovl_put_super(struct super_b
mntput(ufs->upper_mnt);
for (i = 0; i < ufs->numlower; i++)
mntput(ufs->lower_mnt[i]);
+ kfree(ufs->lower_mnt);

kfree(ufs->config.lowerdir);
kfree(ufs->config.upperdir);