linux-stable.git/fs/ext4, branch v5.4.285

ext4: nested locking for xattr inode

2024-11-08T15:20:44+00:00

[ Upstream commit d1bc560e9a9c78d0b2314692847fc8661e0aeb99 ]

Add nested locking with I_MUTEX_XATTR subclass to avoid lockdep warning
while handling xattr inode on file open syscall at ext4_xattr_inode_iget.

Backtrace
EXT4-fs (loop0): Ignoring removed oldalloc option
======================================================
WARNING: possible circular locking dependency detected
5.10.0-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor543/2794 is trying to acquire lock:
ffff8880215e1a48 (&ea_inode->i_rwsem#7/1){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:782 [inline]
ffff8880215e1a48 (&ea_inode->i_rwsem#7/1){+.+.}-{3:3}, at: ext4_xattr_inode_iget+0x42a/0x5c0 fs/ext4/xattr.c:425

but task is already holding lock:
ffff8880215e3278 (&ei->i_data_sem/3){++++}-{3:3}, at: ext4_setattr+0x136d/0x19c0 fs/ext4/inode.c:5559

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&ei->i_data_sem/3){++++}-{3:3}:
       lock_acquire+0x197/0x480 kernel/locking/lockdep.c:5566
       down_write+0x93/0x180 kernel/locking/rwsem.c:1564
       ext4_update_i_disksize fs/ext4/ext4.h:3267 [inline]
       ext4_xattr_inode_write fs/ext4/xattr.c:1390 [inline]
       ext4_xattr_inode_lookup_create fs/ext4/xattr.c:1538 [inline]
       ext4_xattr_set_entry+0x331a/0x3d80 fs/ext4/xattr.c:1662
       ext4_xattr_ibody_set+0x124/0x390 fs/ext4/xattr.c:2228
       ext4_xattr_set_handle+0xc27/0x14e0 fs/ext4/xattr.c:2385
       ext4_xattr_set+0x219/0x390 fs/ext4/xattr.c:2498
       ext4_xattr_user_set+0xc9/0xf0 fs/ext4/xattr_user.c:40
       __vfs_setxattr+0x404/0x450 fs/xattr.c:177
       __vfs_setxattr_noperm+0x11d/0x4f0 fs/xattr.c:208
       __vfs_setxattr_locked+0x1f9/0x210 fs/xattr.c:266
       vfs_setxattr+0x112/0x2c0 fs/xattr.c:283
       setxattr+0x1db/0x3e0 fs/xattr.c:548
       path_setxattr+0x15a/0x240 fs/xattr.c:567
       __do_sys_setxattr fs/xattr.c:582 [inline]
       __se_sys_setxattr fs/xattr.c:578 [inline]
       __x64_sys_setxattr+0xc5/0xe0 fs/xattr.c:578
       do_syscall_64+0x6d/0xa0 arch/x86/entry/common.c:62
       entry_SYSCALL_64_after_hwframe+0x61/0xcb

-> #0 (&ea_inode->i_rwsem#7/1){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:2988 [inline]
       check_prevs_add kernel/locking/lockdep.c:3113 [inline]
       validate_chain+0x1695/0x58f0 kernel/locking/lockdep.c:3729
       __lock_acquire+0x12fd/0x20d0 kernel/locking/lockdep.c:4955
       lock_acquire+0x197/0x480 kernel/locking/lockdep.c:5566
       down_write+0x93/0x180 kernel/locking/rwsem.c:1564
       inode_lock include/linux/fs.h:782 [inline]
       ext4_xattr_inode_iget+0x42a/0x5c0 fs/ext4/xattr.c:425
       ext4_xattr_inode_get+0x138/0x410 fs/ext4/xattr.c:485
       ext4_xattr_move_to_block fs/ext4/xattr.c:2580 [inline]
       ext4_xattr_make_inode_space fs/ext4/xattr.c:2682 [inline]
       ext4_expand_extra_isize_ea+0xe70/0x1bb0 fs/ext4/xattr.c:2774
       __ext4_expand_extra_isize+0x304/0x3f0 fs/ext4/inode.c:5898
       ext4_try_to_expand_extra_isize fs/ext4/inode.c:5941 [inline]
       __ext4_mark_inode_dirty+0x591/0x810 fs/ext4/inode.c:6018
       ext4_setattr+0x1400/0x19c0 fs/ext4/inode.c:5562
       notify_change+0xbb6/0xe60 fs/attr.c:435
       do_truncate+0x1de/0x2c0 fs/open.c:64
       handle_truncate fs/namei.c:2970 [inline]
       do_open fs/namei.c:3311 [inline]
       path_openat+0x29f3/0x3290 fs/namei.c:3425
       do_filp_open+0x20b/0x450 fs/namei.c:3452
       do_sys_openat2+0x124/0x460 fs/open.c:1207
       do_sys_open fs/open.c:1223 [inline]
       __do_sys_open fs/open.c:1231 [inline]
       __se_sys_open fs/open.c:1227 [inline]
       __x64_sys_open+0x221/0x270 fs/open.c:1227
       do_syscall_64+0x6d/0xa0 arch/x86/entry/common.c:62
       entry_SYSCALL_64_after_hwframe+0x61/0xcb

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ei->i_data_sem/3);
                               lock(&ea_inode->i_rwsem#7/1);
                               lock(&ei->i_data_sem/3);
  lock(&ea_inode->i_rwsem#7/1);

 *** DEADLOCK ***

5 locks held by syz-executor543/2794:
 #0: ffff888026fbc448 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x4a/0x2a0 fs/namespace.c:365
 #1: ffff8880215e3488 (&sb->s_type->i_mutex_key#7){++++}-{3:3}, at: inode_lock include/linux/fs.h:782 [inline]
 #1: ffff8880215e3488 (&sb->s_type->i_mutex_key#7){++++}-{3:3}, at: do_truncate+0x1cf/0x2c0 fs/open.c:62
 #2: ffff8880215e3310 (&ei->i_mmap_sem){++++}-{3:3}, at: ext4_setattr+0xec4/0x19c0 fs/ext4/inode.c:5519
 #3: ffff8880215e3278 (&ei->i_data_sem/3){++++}-{3:3}, at: ext4_setattr+0x136d/0x19c0 fs/ext4/inode.c:5559
 #4: ffff8880215e30c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:162 [inline]
 #4: ffff8880215e30c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:5938 [inline]
 #4: ffff8880215e30c8 (&ei->xattr_sem){++++}-{3:3}, at: __ext4_mark_inode_dirty+0x4fb/0x810 fs/ext4/inode.c:6018

stack backtrace:
CPU: 1 PID: 2794 Comm: syz-executor543 Not tainted 5.10.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x177/0x211 lib/dump_stack.c:118
 print_circular_bug+0x146/0x1b0 kernel/locking/lockdep.c:2002
 check_noncircular+0x2cc/0x390 kernel/locking/lockdep.c:2123
 check_prev_add kernel/locking/lockdep.c:2988 [inline]
 check_prevs_add kernel/locking/lockdep.c:3113 [inline]
 validate_chain+0x1695/0x58f0 kernel/locking/lockdep.c:3729
 __lock_acquire+0x12fd/0x20d0 kernel/locking/lockdep.c:4955
 lock_acquire+0x197/0x480 kernel/locking/lockdep.c:5566
 down_write+0x93/0x180 kernel/locking/rwsem.c:1564
 inode_lock include/linux/fs.h:782 [inline]
 ext4_xattr_inode_iget+0x42a/0x5c0 fs/ext4/xattr.c:425
 ext4_xattr_inode_get+0x138/0x410 fs/ext4/xattr.c:485
 ext4_xattr_move_to_block fs/ext4/xattr.c:2580 [inline]
 ext4_xattr_make_inode_space fs/ext4/xattr.c:2682 [inline]
 ext4_expand_extra_isize_ea+0xe70/0x1bb0 fs/ext4/xattr.c:2774
 __ext4_expand_extra_isize+0x304/0x3f0 fs/ext4/inode.c:5898
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:5941 [inline]
 __ext4_mark_inode_dirty+0x591/0x810 fs/ext4/inode.c:6018
 ext4_setattr+0x1400/0x19c0 fs/ext4/inode.c:5562
 notify_change+0xbb6/0xe60 fs/attr.c:435
 do_truncate+0x1de/0x2c0 fs/open.c:64
 handle_truncate fs/namei.c:2970 [inline]
 do_open fs/namei.c:3311 [inline]
 path_openat+0x29f3/0x3290 fs/namei.c:3425
 do_filp_open+0x20b/0x450 fs/namei.c:3452
 do_sys_openat2+0x124/0x460 fs/open.c:1207
 do_sys_open fs/open.c:1223 [inline]
 __do_sys_open fs/open.c:1231 [inline]
 __se_sys_open fs/open.c:1227 [inline]
 __x64_sys_open+0x221/0x270 fs/open.c:1227
 do_syscall_64+0x6d/0xa0 arch/x86/entry/common.c:62
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f0cde4ea229
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:00007ffd81d1c978 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0030656c69662f30 RCX: 00007f0cde4ea229
RDX: 0000000000000089 RSI: 00000000000a0a00 RDI: 00000000200001c0
RBP: 2f30656c69662f2e R08: 0000000000208000 R09: 0000000000208000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd81d1c9c0
R13: 00007ffd81d1ca00 R14: 0000000000080000 R15: 0000000000000003
EXT4-fs error (device loop0): ext4_expand_extra_isize_ea:2730: inode #13: comm syz-executor543: corrupted in-inode xattr

Signed-off-by: Wojciech Gładysz 
Link: https://patch.msgid.link/20240801143827.19135-1-wojciech.gladysz@infogain.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Sasha Levin

ext4: fix inode tree inconsistency caused by ENOMEM

2024-11-08T15:20:43+00:00

commit 3f5424790d4377839093b68c12b130077a4e4510 upstream.

If ENOMEM fails when the extent is splitting, we need to restore the length
of the split extent.
In the ext4_split_extent_at function, only in ext4_ext_create_new_leaf will
it alloc memory and change the shape of the extent tree,even if an ENOMEM
is returned at this time, the extent tree is still self-consistent, Just
restore the split extent lens in the function ext4_split_extent_at.

ext4_split_extent_at
 ext4_ext_insert_extent
  ext4_ext_create_new_leaf
   1)ext4_ext_split
     ext4_find_extent
   2)ext4_ext_grow_indepth
     ext4_find_extent

Signed-off-by: zhanchengbin 
Reviewed-by: Jan Kara 
Link: https://lore.kernel.org/r/20230103022812.130603-1-zhanchengbin1@huawei.com
Signed-off-by: Theodore Ts'o 
Cc: Baokun Li 
Signed-off-by: Greg Kroah-Hartman

ext4: fix incorrect tid assumption in ext4_wait_for_tail_page_commit()

2024-11-08T15:20:40+00:00

commit dd589b0f1445e1ea1085b98edca6e4d5dedb98d0 upstream.

Function ext4_wait_for_tail_page_commit() assumes that '0' is not a valid
value for transaction IDs, which is incorrect.  Don't assume that and invoke
jbd2_log_wait_commit() if the journal had a committing transaction instead.

Signed-off-by: Luis Henriques (SUSE) 
Reviewed-by: Jan Kara 
Link: https://patch.msgid.link/20240724161119.13448-2-luis.henriques@linux.dev
Signed-off-by: Theodore Ts'o 
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman

ext4: fix double brelse() the buffer of the extents path

2024-11-08T15:20:40+00:00

commit dcaa6c31134c0f515600111c38ed7750003e1b9c upstream.

In ext4_ext_try_to_merge_up(), set path[1].p_bh to NULL after it has been
released, otherwise it may be released twice. An example of what triggers
this is as follows:

  split2    map    split1
|--------|-------|--------|

ext4_ext_map_blocks
 ext4_ext_handle_unwritten_extents
  ext4_split_convert_extents
   // path->p_depth == 0
   ext4_split_extent
     // 1. do split1
     ext4_split_extent_at
       |ext4_ext_insert_extent
       |  ext4_ext_create_new_leaf
       |    ext4_ext_grow_indepth
       |      le16_add_cpu(&neh->eh_depth, 1)
       |    ext4_find_extent
       |      // return -ENOMEM
       |// get error and try zeroout
       |path = ext4_find_extent
       |  path->p_depth = 1
       |ext4_ext_try_to_merge
       |  ext4_ext_try_to_merge_up
       |    path->p_depth = 0
       |    brelse(path[1].p_bh)  ---> not set to NULL here
       |// zeroout success
     // 2. update path
     ext4_find_extent
     // 3. do split2
     ext4_split_extent_at
       ext4_ext_insert_extent
         ext4_ext_create_new_leaf
           ext4_ext_grow_indepth
             le16_add_cpu(&neh->eh_depth, 1)
           ext4_find_extent
             path[0].p_bh = NULL;
             path->p_depth = 1
             read_extent_tree_block  ---> return err
             // path[1].p_bh is still the old value
             ext4_free_ext_path
               ext4_ext_drop_refs
                 // path->p_depth == 1
                 brelse(path[1].p_bh)  ---> brelse a buffer twice

Finally got the following WARRNING when removing the buffer from lru:

============================================
VFS: brelse: Trying to free free buffer
WARNING: CPU: 2 PID: 72 at fs/buffer.c:1241 __brelse+0x58/0x90
CPU: 2 PID: 72 Comm: kworker/u19:1 Not tainted 6.9.0-dirty #716
RIP: 0010:__brelse+0x58/0x90
Call Trace:
 
 __find_get_block+0x6e7/0x810
 bdev_getblk+0x2b/0x480
 __ext4_get_inode_loc+0x48a/0x1240
 ext4_get_inode_loc+0xb2/0x150
 ext4_reserve_inode_write+0xb7/0x230
 __ext4_mark_inode_dirty+0x144/0x6a0
 ext4_ext_insert_extent+0x9c8/0x3230
 ext4_ext_map_blocks+0xf45/0x2dc0
 ext4_map_blocks+0x724/0x1700
 ext4_do_writepages+0x12d6/0x2a70
[...]
============================================

Fixes: ecb94f5fdf4b ("ext4: collapse a single extent tree block into the inode if possible")
Cc: stable@kernel.org
Signed-off-by: Baokun Li 
Reviewed-by: Jan Kara 
Reviewed-by: Ojaswin Mujoo 
Tested-by: Ojaswin Mujoo 
Link: https://patch.msgid.link/20240822023545.1994557-9-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

ext4: aovid use-after-free in ext4_ext_insert_extent()

2024-11-08T15:20:40+00:00

commit a164f3a432aae62ca23d03e6d926b122ee5b860d upstream.

As Ojaswin mentioned in Link, in ext4_ext_insert_extent(), if the path is
reallocated in ext4_ext_create_new_leaf(), we'll use the stale path and
cause UAF. Below is a sample trace with dummy values:

ext4_ext_insert_extent
  path = *ppath = 2000
  ext4_ext_create_new_leaf(ppath)
    ext4_find_extent(ppath)
      path = *ppath = 2000
      if (depth > path[0].p_maxdepth)
            kfree(path = 2000);
            *ppath = path = NULL;
      path = kcalloc() = 3000
      *ppath = 3000;
      return path;
  /* here path is still 2000, UAF! */
  eh = path[depth].p_hdr

==================================================================
BUG: KASAN: slab-use-after-free in ext4_ext_insert_extent+0x26d4/0x3330
Read of size 8 at addr ffff8881027bf7d0 by task kworker/u36:1/179
CPU: 3 UID: 0 PID: 179 Comm: kworker/u6:1 Not tainted 6.11.0-rc2-dirty #866
Call Trace:
 
 ext4_ext_insert_extent+0x26d4/0x3330
 ext4_ext_map_blocks+0xe22/0x2d40
 ext4_map_blocks+0x71e/0x1700
 ext4_do_writepages+0x1290/0x2800
[...]

Allocated by task 179:
 ext4_find_extent+0x81c/0x1f70
 ext4_ext_map_blocks+0x146/0x2d40
 ext4_map_blocks+0x71e/0x1700
 ext4_do_writepages+0x1290/0x2800
 ext4_writepages+0x26d/0x4e0
 do_writepages+0x175/0x700
[...]

Freed by task 179:
 kfree+0xcb/0x240
 ext4_find_extent+0x7c0/0x1f70
 ext4_ext_insert_extent+0xa26/0x3330
 ext4_ext_map_blocks+0xe22/0x2d40
 ext4_map_blocks+0x71e/0x1700
 ext4_do_writepages+0x1290/0x2800
 ext4_writepages+0x26d/0x4e0
 do_writepages+0x175/0x700
[...]
==================================================================

So use *ppath to update the path to avoid the above problem.

Reported-by: Ojaswin Mujoo 
Closes: https://lore.kernel.org/r/ZqyL6rmtwl6N4MWR@li-bb2b2a4c-3307-11b2-a85c-8fa5c3a69313.ibm.com
Fixes: 10809df84a4d ("ext4: teach ext4_ext_find_extent() to realloc path if necessary")
Cc: stable@kernel.org
Signed-off-by: Baokun Li 
Reviewed-by: Jan Kara 
Link: https://patch.msgid.link/20240822023545.1994557-7-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

ext4: propagate errors from ext4_find_extent() in ext4_insert_range()

2024-11-08T15:20:40+00:00

commit 369c944ed1d7c3fb7b35f24e4735761153afe7b3 upstream.

Even though ext4_find_extent() returns an error, ext4_insert_range() still
returns 0. This may confuse the user as to why fallocate returns success,
but the contents of the file are not as expected. So propagate the error
returned by ext4_find_extent() to avoid inconsistencies.

Fixes: 331573febb6a ("ext4: Add support FALLOC_FL_INSERT_RANGE for fallocate")
Cc: stable@kernel.org
Signed-off-by: Baokun Li 
Reviewed-by: Jan Kara 
Reviewed-by: Ojaswin Mujoo 
Tested-by: Ojaswin Mujoo 
Link: https://patch.msgid.link/20240822023545.1994557-11-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

ext4: no need to continue when the number of entries is 1

2024-11-08T15:20:40+00:00

commit 1a00a393d6a7fb1e745a41edd09019bd6a0ad64c upstream.

Fixes: ac27a0ec112a ("[PATCH] ext4: initial copy of files from ext3")
Reported-by: syzbot+ae688d469e36fb5138d0@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=ae688d469e36fb5138d0
Signed-off-by: Edward Adam Davis 
Reported-and-tested-by: syzbot+ae688d469e36fb5138d0@syzkaller.appspotmail.com
Link: https://patch.msgid.link/tencent_BE7AEE6C7C2D216CB8949CE8E6EE7ECC2C0A@qq.com
Signed-off-by: Theodore Ts'o 
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman

ext4: fix i_data_sem unlock order in ext4_ind_migrate()

2024-11-08T15:20:39+00:00

[ Upstream commit cc749e61c011c255d81b192a822db650c68b313f ]

Fuzzing reports a possible deadlock in jbd2_log_wait_commit.

This issue is triggered when an EXT4_IOC_MIGRATE ioctl is set to require
synchronous updates because the file descriptor is opened with O_SYNC.
This can lead to the jbd2_journal_stop() function calling
jbd2_might_wait_for_commit(), potentially causing a deadlock if the
EXT4_IOC_MIGRATE call races with a write(2) system call.

This problem only arises when CONFIG_PROVE_LOCKING is enabled. In this
case, the jbd2_might_wait_for_commit macro locks jbd2_handle in the
jbd2_journal_stop function while i_data_sem is locked. This triggers
lockdep because the jbd2_journal_start function might also lock the same
jbd2_handle simultaneously.

Found by Linux Verification Center (linuxtesting.org) with syzkaller.

Reviewed-by: Ritesh Harjani (IBM) 
Co-developed-by: Mikhail Ukhin 
Signed-off-by: Mikhail Ukhin 
Signed-off-by: Artem Sadovnikov 
Rule: add
Link: https://lore.kernel.org/stable/20240404095000.5872-1-mish.uxin2012%40yandex.ru
Link: https://patch.msgid.link/20240829152210.2754-1-ancowi69@gmail.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Sasha Levin

ext4: ext4_search_dir should return a proper error

2024-11-08T15:20:39+00:00

[ Upstream commit cd69f8f9de280e331c9e6ff689ced0a688a9ce8f ]

ext4_search_dir currently returns -1 in case of a failure, while it returns
0 when the name is not found. In such failure cases, it should return an
error code instead.

This becomes even more important when ext4_find_inline_entry returns an
error code as well in the next commit.

-EFSCORRUPTED seems appropriate as such error code as these failures would
be caused by unexpected record lengths and is in line with other instances
of ext4_check_dir_entry failures.

In the case of ext4_dx_find_entry, the current use of ERR_BAD_DX_DIR was
left as is to reduce the risk of regressions.

Signed-off-by: Thadeu Lima de Souza Cascardo 
Link: https://patch.msgid.link/20240821152324.3621860-2-cascardo@igalia.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Sasha Levin

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

2024-11-08T15:20:30+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