Ubuntu: (CVE-2022-49381): linux vulnerability

In the Linux kernel, the following vulnerability has been resolved:

jffs2: fix memory leak in jffs2_do_fill_super

If jffs2_iget() or d_make_root() in jffs2_do_fill_super() returns
an error, we can observe the following kmemleak report:

--------------------------------------------
unreferenced object 0xffff888105a65340 (size 64):
comm "mount", pid 710, jiffies 4302851558 (age 58.239s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[] kmem_cache_alloc_trace+0x475/0x8a0
[] jffs2_sum_init+0x96/0x1a0
[] jffs2_do_mount_fs+0x745/0x2120
[] jffs2_do_fill_super+0x35c/0x810
[] jffs2_fill_super+0x2b9/0x3b0
[...]
unreferenced object 0xffff8881bd7f0000 (size 65536):
comm "mount", pid 710, jiffies 4302851558 (age 58.239s)
hex dump (first 32 bytes):
bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb ................
bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb ................
backtrace:
[] kmalloc_order+0xda/0x110
[] kmalloc_order_trace+0x21/0x130
[] __kmalloc+0x711/0x8a0
[] jffs2_sum_init+0xd9/0x1a0
[] jffs2_do_mount_fs+0x745/0x2120
[] jffs2_do_fill_super+0x35c/0x810
[] jffs2_fill_super+0x2b9/0x3b0
[...]
--------------------------------------------

This is because the resources allocated in jffs2_sum_init() are not
released. Call jffs2_sum_exit() to release these resources to solve
the problem.