Liyuan Pang d133e30aab ubi: fastmap: fix ubi->fm memory leak
The problem is that scan_fast() allocate memory for ubi->fm
and ubi->fm->e[x], but if the following attach process fails
in ubi_wl_init or ubi_read_volume_table, the whole attach
process will fail without executing ubi_wl_close to free the
memory under ubi->fm.

Fix this by add a new ubi_free_fastmap function in fastmap.c
to free the memory allocated for fm.

If SLUB_DEBUG and KUNIT are enabled, the following warning messages
will show:
ubi0: detaching mtd0
ubi0: mtd0 is detached
ubi0: default fastmap pool size: 200
ubi0: default fastmap WL pool size: 100
ubi0: attaching mtd0
ubi0: attached by fastmap
ubi0: fastmap pool size: 200
ubi0: fastmap WL pool size: 100
ubi0 error: ubi_wl_init [ubi]: no enough physical eraseblocks (4, need 203)
ubi0 error: ubi_attach_mtd_dev [ubi]: failed to attach mtd0, error -28
UBI error: cannot attach mtd0
=================================================================
BUG ubi_wl_entry_slab (Tainted: G    B      O L   ): Objects remaining in ubi_wl_entry_slab on __kmem_cache_shutdown()
-----------------------------------------------------------------------------

Slab 0xffff2fd23a40cd00 objects=22 used=1 fp=0xffff2fd1d0334fd8 flags=0x883fffc010200(slab|head|section=34|node=0|zone=1|lastcpupid=0x7fff)
CPU: 0 PID: 5884 Comm: insmod Tainted: G    B      O L    5.10.0 #1
Hardware name: LS1043A RDB Board (DT)
Call trace:
 dump_backtrace+0x0/0x198
 show_stack+0x18/0x28
 dump_stack+0xe8/0x15c
 slab_err+0x94/0xc0
 __kmem_cache_shutdown+0x1fc/0x39c
 kmem_cache_destroy+0x48/0x138
 ubi_init+0x1d4/0xf34 [ubi]
 do_one_initcall+0xb4/0x24c
 do_init_module+0x4c/0x1dc
 load_module+0x212c/0x2260
 __se_sys_finit_module+0xb4/0xd8
 __arm64_sys_finit_module+0x18/0x28
 el0_svc_common.constprop.0+0x78/0x1a0
 do_el0_svc+0x78/0x90
 el0_svc+0x20/0x38
 el0_sync_handler+0xf0/0x140
 normal+0x3d8/0x400
Object 0xffff2fd1d0334e68 @offset=3688
Allocated in ubi_scan_fastmap+0xf04/0xf40 [ubi] age=80 cpu=0 pid=5884
	__slab_alloc.isra.21+0x6c/0xb4
	kmem_cache_alloc+0x1e4/0x80c
	ubi_scan_fastmap+0xf04/0xf40 [ubi]
	ubi_attach+0x1f0/0x3a8 [ubi]
	ubi_attach_mtd_dev+0x810/0xbc8 [ubi]
	ubi_init+0x238/0xf34 [ubi]
	do_one_initcall+0xb4/0x24c
	do_init_module+0x4c/0x1dc
	load_module+0x212c/0x2260
	__se_sys_finit_module+0xb4/0xd8
	__arm64_sys_finit_module+0x18/0x28
	el0_svc_common.constprop.0+0x78/0x1a0
	do_el0_svc+0x78/0x90
	el0_svc+0x20/0x38
	el0_sync_handler+0xf0/0x140
	normal+0x3d8/0x400

Link: https://bugzilla.kernel.org/show_bug.cgi?id=220744

Signed-off-by: Liyuan Pang <pangliyuan1@huawei.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2025-11-28 21:49:01 +01:00
2025-11-15 10:52:01 -08:00
2025-11-16 14:25:38 -08:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Description
Linux kernel source tree
Readme 7.2 GiB
Languages
C 97.1%
Assembly 1%
Shell 0.6%
Rust 0.4%
Python 0.4%
Other 0.3%