linux-toradex.git/drivers/mtd/ubi/attach.c, branch v6.19

ubi: fastmap: fix ubi->fm memory leak

2025-11-28T20:49:01+00:00

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 
Reviewed-by: Zhihao Cheng 
Signed-off-by: Richard Weinberger

ubi: fastmap: Fix duplicate slab cache names while attaching

2024-11-14T18:45:28+00:00

Since commit 4c39529663b9 ("slab: Warn on duplicate cache names when
DEBUG_VM=y"), the duplicate slab cache names can be detected and a
kernel WARNING is thrown out.
In UBI fast attaching process, alloc_ai() could be invoked twice
with the same slab cache name 'ubi_aeb_slab_cache', which will trigger
following warning messages:
 kmem_cache of name 'ubi_aeb_slab_cache' already exists
 WARNING: CPU: 0 PID: 7519 at mm/slab_common.c:107
          __kmem_cache_create_args+0x100/0x5f0
 Modules linked in: ubi(+) nandsim [last unloaded: nandsim]
 CPU: 0 UID: 0 PID: 7519 Comm: modprobe Tainted: G 6.12.0-rc2
 RIP: 0010:__kmem_cache_create_args+0x100/0x5f0
 Call Trace:
   __kmem_cache_create_args+0x100/0x5f0
   alloc_ai+0x295/0x3f0 [ubi]
   ubi_attach+0x3c3/0xcc0 [ubi]
   ubi_attach_mtd_dev+0x17cf/0x3fa0 [ubi]
   ubi_init+0x3fb/0x800 [ubi]
   do_init_module+0x265/0x7d0
   __x64_sys_finit_module+0x7a/0xc0

The problem could be easily reproduced by loading UBI device by fastmap
with CONFIG_DEBUG_VM=y.
Fix it by using different slab names for alloc_ai() callers.

Fixes: d2158f69a7d4 ("UBI: Remove alloc_ai() slab name from parameter list")
Fixes: fdf10ed710c0 ("ubi: Rework Fastmap attach base code")
Signed-off-by: Zhihao Cheng 
Signed-off-by: Richard Weinberger

mtd: Convert fallthrough comments into statements

2020-03-30T08:14:54+00:00

Use Joe Perches cvt_fallthrough.pl script to convert

	/* fallthrough */

comments (and its derivatives) into a

	fallthrough;

statement. This automatically drops useless ones.

Do it MTD-wide.

Signed-off-by: Miquel Raynal 
Acked-by: Vignesh Raghavendra 
Acked-by: Tudor Ambarus 
Acked-by: Richard Weinberger 
Link: https://lore.kernel.org/linux-mtd/20200325212115.14170-1-miquel.raynal@bootlin.com

ubi: Free the normal volumes in error paths of ubi_attach_mtd_dev()

2020-01-16T22:35:59+00:00

The allocated normal volumes saved in ubi->volumes are not freed
in the error paths in ubi_attach_mtd_dev() and its callees (e.g.
ubi_attach() and ubi_read_volume_table()).

These normal volumes should be freed through kill_volumes() and
vol_release(), but ubi_attach_mtd_dev() may fail before
calling uif_init(), and there will be memory leaks.

So adding a new helper ubi_free_all_volumes() to free the normal
and the internal volumes. And in order to prevent double-free
of volume, reset ubi->volumes[i] to NULL after freeing.

Signed-off-by: Hou Tao 
Signed-off-by: Richard Weinberger

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

2019-05-30T18:26:35+00:00

Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Allison Randal 
Reviewed-by: Richard Fontana 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman

ubi: Mark expected switch fall-throughs

2018-10-23T11:46:48+00:00

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Addresses-Coverity-ID: 1373884 ("Missing break in switch")
Addresses-Coverity-ID: 114869 ("Missing break in switch")
Addresses-Coverity-ID: 114870 ("Missing break in switch")
Signed-off-by: Gustavo A. R. Silva 
Signed-off-by: Richard Weinberger

UBI: introduce the VID buffer concept

2016-10-02T20:48:14+00:00

Currently, all VID headers are allocated and freed using the
ubi_zalloc_vid_hdr() and ubi_free_vid_hdr() function. These functions
make sure to align allocation on ubi->vid_hdr_alsize and adjust the
vid_hdr pointer to match the ubi->vid_hdr_shift requirements.
This works fine, but is a bit convoluted.
Moreover, the future introduction of LEB consolidation (needed to support
MLC/TLC NANDs) will allows a VID buffer to contain more than one VID
header.

Hence the creation of a ubi_vid_io_buf struct to attach extra information
to the VID header.

We currently only store the actual pointer of the underlying buffer, but
will soon add the number of VID headers contained in the buffer.

Signed-off-by: Boris Brezillon 
Signed-off-by: Richard Weinberger

UBI: move the global ech and vidh variables into struct ubi_attach_info

2016-10-02T20:48:14+00:00

Even if it works fine with those global variables, attaching the
temporary ech and vidh objects used during UBI scan to the
ubi_attach_info object sounds like a more future-proof option.

For example, attaching several UBI devices in parallel is prevented by
this use of global variable. And also because global variables should
be avoided in general.

Signed-off-by: Boris Brezillon 
Signed-off-by: Richard Weinberger

UBI: provide helpers to allocate and free aeb elements

2016-10-02T20:48:14+00:00

This not only hides the aeb allocation internals (which is always good in
case we ever want to change the allocation system), but also helps us
factorize the initialization of some common fields (ec and pnum).

Signed-off-by: Boris Brezillon 
Signed-off-by: Richard Weinberger

UBI: factorize destroy_av() and ubi_remove_av() code

2016-10-02T20:48:14+00:00

Those functions are pretty much doing the same thing, except
ubi_remove_av() is putting the aeb elements attached to the volume into
the ai->erase list and the destroy_av() is freeing them.

Rework destroy_av() to handle both cases.

Signed-off-by: Boris Brezillon 
Signed-off-by: Richard Weinberger