[3.13.y.z extended stable] Patch "UBI: add missing kmem_cache_free() in process_pool_aeb error path" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    UBI: add missing kmem_cache_free() in process_pool_aeb error path

to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue

This patch is scheduled to be released in version 3.13.11.10.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From f5fce7754cedf99ce0f500b5634b5c263c68310f Mon Sep 17 00:00:00 2001
From: Richard Genoud <richard.genoud at gmail.com>
Date: Tue, 9 Sep 2014 14:25:01 +0200
Subject: UBI: add missing kmem_cache_free() in process_pool_aeb error path

commit 1bf1890e86869032099b539bc83b098be12fc5a7 upstream.

I ran into this error after a ubiupdatevol, because I forgot to backport
e9110361a9a4 UBI: fix the volumes tree sorting criteria.

UBI error: process_pool_aeb: orphaned volume in fastmap pool
UBI error: ubi_scan_fastmap: Attach by fastmap failed, doing a full scan!
kmem_cache_destroy ubi_ainf_peb_slab: Slab cache still has objects
CPU: 0 PID: 1 Comm: swapper Not tainted 3.14.18-00053-gf05cac8dbf85 #1
[<c000d298>] (unwind_backtrace) from [<c000baa8>] (show_stack+0x10/0x14)
[<c000baa8>] (show_stack) from [<c01b7a68>] (destroy_ai+0x230/0x244)
[<c01b7a68>] (destroy_ai) from [<c01b8fd4>] (ubi_attach+0x98/0x1ec)
[<c01b8fd4>] (ubi_attach) from [<c01ade90>] (ubi_attach_mtd_dev+0x2b8/0x868)
[<c01ade90>] (ubi_attach_mtd_dev) from [<c038b510>] (ubi_init+0x1dc/0x2ac)
[<c038b510>] (ubi_init) from [<c0008860>] (do_one_initcall+0x94/0x140)
[<c0008860>] (do_one_initcall) from [<c037aadc>] (kernel_init_freeable+0xe8/0x1b0)
[<c037aadc>] (kernel_init_freeable) from [<c02730ac>] (kernel_init+0x8/0xe4)
[<c02730ac>] (kernel_init) from [<c00093f0>] (ret_from_fork+0x14/0x24)
UBI: scanning is finished

Freeing the cache in the error path fixes the Slab error.

Tested on at91sam9g35 (3.14.18+fastmap backports)

Signed-off-by: Richard Genoud <richard.genoud at gmail.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/mtd/ubi/fastmap.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/mtd/ubi/fastmap.c b/drivers/mtd/ubi/fastmap.c
index ead8613..fdbaf7a 100644
--- a/drivers/mtd/ubi/fastmap.c
+++ b/drivers/mtd/ubi/fastmap.c
@@ -330,6 +330,7 @@ static int process_pool_aeb(struct ubi_device *ubi, struct ubi_attach_info *ai,
 		av = tmp_av;
 	else {
 		ubi_err("orphaned volume in fastmap pool!");
+		kmem_cache_free(ai->aeb_slab_cache, new_aeb);
 		return UBI_BAD_FASTMAP;
 	}

--
1.9.1