linux-stable.git/fs/ext4/inline.c, branch linux-6.10.y

ext4: avoid OOB when system.data xattr changes underneath the filesystem

2024-10-04T14:32:57+00:00

[ Upstream commit c6b72f5d82b1017bad80f9ebf502832fc321d796 ]

When looking up for an entry in an inlined directory, if e_value_offs is
changed underneath the filesystem by some change in the block device, it
will lead to an out-of-bounds access that KASAN detects as an UAF.

EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.
loop0: detected capacity change from 2048 to 2047
==================================================================
BUG: KASAN: use-after-free in ext4_search_dir+0xf2/0x1c0 fs/ext4/namei.c:1500
Read of size 1 at addr ffff88803e91130f by task syz-executor269/5103

CPU: 0 UID: 0 PID: 5103 Comm: syz-executor269 Not tainted 6.11.0-rc4-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 ext4_search_dir+0xf2/0x1c0 fs/ext4/namei.c:1500
 ext4_find_inline_entry+0x4be/0x5e0 fs/ext4/inline.c:1697
 __ext4_find_entry+0x2b4/0x1b30 fs/ext4/namei.c:1573
 ext4_lookup_entry fs/ext4/namei.c:1727 [inline]
 ext4_lookup+0x15f/0x750 fs/ext4/namei.c:1795
 lookup_one_qstr_excl+0x11f/0x260 fs/namei.c:1633
 filename_create+0x297/0x540 fs/namei.c:3980
 do_symlinkat+0xf9/0x3a0 fs/namei.c:4587
 __do_sys_symlinkat fs/namei.c:4610 [inline]
 __se_sys_symlinkat fs/namei.c:4607 [inline]
 __x64_sys_symlinkat+0x95/0xb0 fs/namei.c:4607
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3e73ced469
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 21 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff4d40c258 EFLAGS: 00000246 ORIG_RAX: 000000000000010a
RAX: ffffffffffffffda RBX: 0032656c69662f2e RCX: 00007f3e73ced469
RDX: 0000000020000200 RSI: 00000000ffffff9c RDI: 00000000200001c0
RBP: 0000000000000000 R08: 00007fff4d40c290 R09: 00007fff4d40c290
R10: 0023706f6f6c2f76 R11: 0000000000000246 R12: 00007fff4d40c27c
R13: 0000000000000003 R14: 431bde82d7b634db R15: 00007fff4d40c2b0
 

Calling ext4_xattr_ibody_find right after reading the inode with
ext4_get_inode_loc will lead to a check of the validity of the xattrs,
avoiding this problem.

Reported-by: syzbot+0c2508114d912a54ee79@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=0c2508114d912a54ee79
Fixes: e8e948e7802a ("ext4: let ext4_find_entry handle inline data")
Signed-off-by: Thadeu Lima de Souza Cascardo 
Link: https://patch.msgid.link/20240821152324.3621860-5-cascardo@igalia.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Sasha Levin

ext4: return error on ext4_find_inline_entry

2024-10-04T14:32:57+00:00

[ Upstream commit 4d231b91a944f3cab355fce65af5871fb5d7735b ]

In case of errors when reading an inode from disk or traversing inline
directory entries, return an error-encoded ERR_PTR instead of returning
NULL. ext4_find_inline_entry only caller, __ext4_find_entry already returns
such encoded errors.

Signed-off-by: Thadeu Lima de Souza Cascardo 
Link: https://patch.msgid.link/20240821152324.3621860-3-cascardo@igalia.com
Signed-off-by: Theodore Ts'o 
Stable-dep-of: c6b72f5d82b1 ("ext4: avoid OOB when system.data xattr changes underneath the filesystem")
Signed-off-by: Sasha Levin

ext4: fix uninitialized variable in ext4_inlinedir_to_tree

2024-08-14T13:34:16+00:00

[ Upstream commit 8dc9c3da79c84b13fdb135e2fb0a149a8175bffe ]

Syzbot has found an uninit-value bug in ext4_inlinedir_to_tree

This error happens because ext4_inlinedir_to_tree does not
handle the case when ext4fs_dirhash returns an error

This can be avoided by checking the return value of ext4fs_dirhash
and propagating the error,
similar to how it's done with ext4_htree_store_dirent

Signed-off-by: Xiaxi Shen 
Reported-and-tested-by: syzbot+eaba5abe296837a640c0@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=eaba5abe296837a640c0
Link: https://patch.msgid.link/20240501033017.220000-1-shenxiaxi26@gmail.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Sasha Levin

mm: add folio_zero_tail() and use it in ext4

2023-12-11T00:51:36+00:00

Patch series "Add folio_zero_tail() and folio_fill_tail()".

I'm trying to make it easier for filesystems with tailpacking / stuffing /
inline data to use folios.  The primary function here is
folio_fill_tail().  You give it a pointer to memory where the data
currently is, and it takes care of copying it into the folio at that
offset.  That works for gfs2 & iomap.  Then There's Ext4.  Rather than gin
up some kind of specialist "Here's a two pointers to two blocks of memory"
routine, just let it do its current thing, and let it call
folio_zero_tail(), which is also called by folio_fill_tail().

Other filesystems can be converted later; these ones seemed like good
examples as they're already partly or completely converted to folios.


This patch (of 3):

Instead of unmapping the folio after copying the data to it, then mapping
it again to zero the tail, provide folio_zero_tail() to zero the tail of
an already-mapped folio.

[akpm@linux-foundation.org: fix kerneldoc argument ordering]
Link: https://lkml.kernel.org/r/20231107212643.3490372-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20231107212643.3490372-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) 
Reviewed-by: Andreas Gruenbacher 
Cc: Darrick J. Wong 
Cc: Theodore Ts'o 
Signed-off-by: Andrew Morton

ext4: convert to new timestamp accessors

2023-10-18T11:26:21+00:00

Convert to using the new inode timestamp accessor functions.

Signed-off-by: Jeff Layton 
Link: https://lore.kernel.org/r/20231004185347.80880-33-jlayton@kernel.org
Signed-off-by: Christian Brauner

Merge tag 'ext4_for_linus-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2023-08-31T22:18:15+00:00

Pull ext4 updates from Ted Ts'o:
 "Many ext4 and jbd2 cleanups and bug fixes:

   - Cleanups in the ext4 remount code when going to and from read-only

   - Cleanups in ext4's multiblock allocator

   - Cleanups in the jbd2 setup/mounting code paths

   - Performance improvements when appending to a delayed allocation file

   - Miscellaneous syzbot and other bug fixes"

* tag 'ext4_for_linus-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (60 commits)
  ext4: fix slab-use-after-free in ext4_es_insert_extent()
  libfs: remove redundant checks of s_encoding
  ext4: remove redundant checks of s_encoding
  ext4: reject casefold inode flag without casefold feature
  ext4: use LIST_HEAD() to initialize the list_head in mballoc.c
  ext4: do not mark inode dirty every time when appending using delalloc
  ext4: rename s_error_work to s_sb_upd_work
  ext4: add periodic superblock update check
  ext4: drop dio overwrite only flag and associated warning
  ext4: add correct group descriptors and reserved GDT blocks to system zone
  ext4: remove unused function declaration
  ext4: mballoc: avoid garbage value from err
  ext4: use sbi instead of EXT4_SB(sb) in ext4_mb_new_blocks_simple()
  ext4: change the type of blocksize in ext4_mb_init_cache()
  ext4: fix unttached inode after power cut with orphan file feature enabled
  jbd2: correct the end of the journal recovery scan range
  ext4: ext4_get_{dev}_journal return proper error value
  ext4: cleanup ext4_get_dev_journal() and ext4_get_journal()
  jbd2: jbd2_journal_init_{dev,inode} return proper error return value
  jbd2: drop useless error tag in jbd2_journal_wipe()
  ...

ext4: make ext4_forced_shutdown() take struct super_block

2023-07-29T22:37:24+00:00

Currently ext4_forced_shutdown() takes struct ext4_sb_info but most
callers need to get it from struct super_block anyway. So just pass in
struct super_block to save all callers from some boilerplate code. No
functional changes.

Signed-off-by: Jan Kara 
Link: https://lore.kernel.org/r/20230616165109.21695-3-jack@suse.cz
Signed-off-by: Theodore Ts'o

ext4: convert to ctime accessor functions

2023-07-24T08:29:54+00:00

In later patches, we're going to change how the inode's ctime field is
used. Switch to using accessor functions instead of raw accesses of
inode->i_ctime.

Signed-off-by: Jeff Layton 
Signed-off-by: Jan Kara 
Message-Id: <20230705190309.579783-40-jlayton@kernel.org>
Signed-off-by: Christian Brauner

ext4: make ext4_es_remove_extent() return void

2023-06-26T23:35:12+00:00

Now ext4_es_remove_extent() never fails, so make it return void.

Signed-off-by: Baokun Li 
Reviewed-by: Jan Kara 
Link: https://lore.kernel.org/r/20230424033846.4732-10-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o

ext4: Make ext4_write_inline_data_end() use folio

2023-06-15T04:02:10+00:00

ext4_write_inline_data_end() is completely converted to work with folio.
Also all callers of ext4_write_inline_data_end() already works on folio
except ext4_da_write_end(). Mostly for consistency and saving few
instructions maybe, this patch just converts ext4_da_write_end() to work
with folio which makes the last caller of ext4_write_inline_data_end()
also converted to work with folio.
We then make ext4_write_inline_data_end() take folio instead of page.

Reviewed-by: Matthew Wilcox (Oracle) 
Signed-off-by: Ritesh Harjani (IBM) 
Link: https://lore.kernel.org/r/1bcea771720ff451a5a59b3f1bcd5fae51cb7ce7.1684122756.git.ritesh.list@gmail.com
Signed-off-by: Theodore Ts'o