From: Li Zetao <lizetao1@huawei.com>
Date: Fri, 21 Oct 2022 10:21:57 +0000 (+0800)
Subject: ubi: Fix unreferenced object reported by kmemleak in ubi_resize_volume()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=1e591ea072df7211f64542a09482b5f81cb3ad27;p=linux.git

ubi: Fix unreferenced object reported by kmemleak in ubi_resize_volume()

There is a memory leaks problem reported by kmemleak:

unreferenced object 0xffff888102007a00 (size 128):
  comm "ubirsvol", pid 32090, jiffies 4298464136 (age 2361.231s)
  hex dump (first 32 bytes):
ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff  ................
ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff  ................
  backtrace:
[<ffffffff8176cecd>] __kmalloc+0x4d/0x150
[<ffffffffa02a9a36>] ubi_eba_create_table+0x76/0x170 [ubi]
[<ffffffffa029764e>] ubi_resize_volume+0x1be/0xbc0 [ubi]
[<ffffffffa02a3321>] ubi_cdev_ioctl+0x701/0x1850 [ubi]
[<ffffffff81975d2d>] __x64_sys_ioctl+0x11d/0x170
[<ffffffff83c142a5>] do_syscall_64+0x35/0x80
[<ffffffff83e0006a>] entry_SYSCALL_64_after_hwframe+0x46/0xb0

This is due to a mismatch between create and destroy interfaces, and
in detail that "new_eba_tbl" created by ubi_eba_create_table() but
destroyed by kfree(), while will causing "new_eba_tbl->entries" not
freed.

Fix it by replacing kfree(new_eba_tbl) with
ubi_eba_destroy_table(new_eba_tbl)

Fixes: 799dca34ac54 ("UBI: hide EBA internals")
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
---

diff --git a/drivers/mtd/ubi/vmt.c b/drivers/mtd/ubi/vmt.c
index 74637575346e8..9fbc64b997cef 100644
--- a/drivers/mtd/ubi/vmt.c
+++ b/drivers/mtd/ubi/vmt.c
@@ -515,7 +515,7 @@ out_acc:
 	return err;
 
 out_free:
-	kfree(new_eba_tbl);
+	ubi_eba_destroy_table(new_eba_tbl);
 	return err;
 }