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Josef Bacik e03418abde btrfs: make sure that WRITTEN is set on all metadata blocks
We previously would call btrfs_check_leaf() if we had the check
integrity code enabled, which meant that we could only run the extended
leaf checks if we had WRITTEN set on the header flags.

This leaves a gap in our checking, because we could end up with
corruption on disk where WRITTEN isn't set on the leaf, and then the
extended leaf checks don't get run which we rely on to validate all of
the item pointers to make sure we don't access memory outside of the
extent buffer.

However, since 732fab95ab ("btrfs: check-integrity: remove
CONFIG_BTRFS_FS_CHECK_INTEGRITY option") we no longer call
btrfs_check_leaf() from btrfs_mark_buffer_dirty(), which means we only
ever call it on blocks that are being written out, and thus have WRITTEN
set, or that are being read in, which should have WRITTEN set.

Add checks to make sure we have WRITTEN set appropriately, and then make
sure __btrfs_check_leaf() always does the item checking.  This will
protect us from file systems that have been corrupted and no longer have
WRITTEN set on some of the blocks.

This was hit on a crafted image tweaking the WRITTEN bit and reported by
KASAN as out-of-bound access in the eb accessors. The example is a dir
item at the end of an eb.

  [2.042] BTRFS warning (device loop1): bad eb member start: ptr 0x3fff start 30572544 member offset 16410 size 2
  [2.040] general protection fault, probably for non-canonical address 0xe0009d1000000003: 0000 [#1] PREEMPT SMP KASAN NOPTI
  [2.537] KASAN: maybe wild-memory-access in range [0x0005088000000018-0x000508800000001f]
  [2.729] CPU: 0 PID: 2587 Comm: mount Not tainted 6.8.2 #1
  [2.729] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
  [2.621] RIP: 0010:btrfs_get_16+0x34b/0x6d0
  [2.621] RSP: 0018:ffff88810871fab8 EFLAGS: 00000206
  [2.621] RAX: 0000a11000000003 RBX: ffff888104ff8720 RCX: ffff88811b2288c0
  [2.621] RDX: dffffc0000000000 RSI: ffffffff81dd8aca RDI: ffff88810871f748
  [2.621] RBP: 000000000000401a R08: 0000000000000001 R09: ffffed10210e3ee9
  [2.621] R10: ffff88810871f74f R11: 205d323430333737 R12: 000000000000001a
  [2.621] R13: 000508800000001a R14: 1ffff110210e3f5d R15: ffffffff850011e8
  [2.621] FS:  00007f56ea275840(0000) GS:ffff88811b200000(0000) knlGS:0000000000000000
  [2.621] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [2.621] CR2: 00007febd13b75c0 CR3: 000000010bb50000 CR4: 00000000000006f0
  [2.621] Call Trace:
  [2.621]  <TASK>
  [2.621]  ? show_regs+0x74/0x80
  [2.621]  ? die_addr+0x46/0xc0
  [2.621]  ? exc_general_protection+0x161/0x2a0
  [2.621]  ? asm_exc_general_protection+0x26/0x30
  [2.621]  ? btrfs_get_16+0x33a/0x6d0
  [2.621]  ? btrfs_get_16+0x34b/0x6d0
  [2.621]  ? btrfs_get_16+0x33a/0x6d0
  [2.621]  ? __pfx_btrfs_get_16+0x10/0x10
  [2.621]  ? __pfx_mutex_unlock+0x10/0x10
  [2.621]  btrfs_match_dir_item_name+0x101/0x1a0
  [2.621]  btrfs_lookup_dir_item+0x1f3/0x280
  [2.621]  ? __pfx_btrfs_lookup_dir_item+0x10/0x10
  [2.621]  btrfs_get_tree+0xd25/0x1910

Reported-by: lei lu <llfamsec@gmail.com>
CC: stable@vger.kernel.org # 6.7+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ copy more details from report ]
Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-02 22:11:13 +02:00
arch powerpc fixes for 6.8 #5 2024-03-03 09:47:19 -08:00
block block: sed-opal: handle empty atoms when parsing response 2024-02-16 15:52:45 -07:00
certs This update includes the following changes: 2023-11-02 16:15:30 -10:00
crypto crypto: lskcipher - Copy IV in lskcipher glue code always 2024-02-24 08:37:24 +08:00
Documentation Including fixes from bluetooth, WiFi and netfilter. 2024-02-29 12:40:20 -08:00
drivers phy second set of fixes for 6.8 2024-03-03 09:56:49 -08:00
fs btrfs: make sure that WRITTEN is set on all metadata blocks 2024-05-02 22:11:13 +02:00
include btrfs: qgroup: validate btrfs_qgroup_inherit parameter 2024-03-05 17:13:24 +01:00
init update workarounds for gcc "asm goto" issue 2024-02-15 11:14:33 -08:00
io_uring io_uring/net: fix multishot accept overflow handling 2024-02-14 18:30:19 -07:00
ipc shm: Slim down dependencies 2023-12-20 19:26:31 -05:00
kernel Probes fixes for v6.8-rc5: 2024-03-01 11:17:23 -08:00
lib Including fixes from bluetooth, WiFi and netfilter. 2024-02-29 12:40:20 -08:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm 6 hotfixes. 3 are cc:stable and the remainder address post-6.7 issues 2024-02-27 16:44:15 -08:00
net bluetooth pull request for net: 2024-02-29 09:10:24 -08:00
rust Rust changes for v6.8 2024-01-11 13:05:41 -08:00
samples work around gcc bugs with 'asm goto' with outputs 2024-02-09 15:57:48 -08:00
scripts RISC-V Fixes for 6.8-rc7 2024-03-01 12:44:33 -08:00
security tomoyo: fix UAF write bug in tomoyo_write_control() 2024-03-01 11:14:00 -08:00
sound ASoC: Fixes for v6.8 2024-02-29 08:29:04 +01:00
tools powerpc fixes for 6.8 #5 2024-03-03 09:47:19 -08:00
usr Kbuild updates for v6.8 2024-01-18 17:57:07 -08:00
virt Generic: 2024-01-17 13:03:37 -08:00
.clang-format clang-format: Update with v6.7-rc4's for_each macro list 2023-12-08 23:54:38 +01:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.editorconfig Add .editorconfig file for basic formatting 2023-12-28 16:22:47 +09:00
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore Add .editorconfig file for basic formatting 2023-12-28 16:22:47 +09:00
.mailmap MAINTAINERS: mailmap: update Shakeel's email address 2024-02-20 14:20:50 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: supplement of zswap maintainers update 2024-01-25 23:52:21 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS RISC-V Fixes for 6.8-rc7 2024-03-01 12:44:33 -08:00
Makefile Linux 6.8-rc7 2024-03-03 13:02:52 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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 Restructured Text 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.