linux-stable.git/fs/ext4, branch v6.2.15

ext4: fix use-after-free read in ext4_find_extent for bigalloc + inline

2023-05-11T14:11:30+00:00

[ Upstream commit 835659598c67907b98cd2aa57bb951dfaf675c69 ]

Syzbot found the following issue:
loop0: detected capacity change from 0 to 2048
EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 without journal. Quota mode: none.
==================================================================
BUG: KASAN: use-after-free in ext4_ext_binsearch_idx fs/ext4/extents.c:768 [inline]
BUG: KASAN: use-after-free in ext4_find_extent+0x76e/0xd90 fs/ext4/extents.c:931
Read of size 4 at addr ffff888073644750 by task syz-executor420/5067

CPU: 0 PID: 5067 Comm: syz-executor420 Not tainted 6.2.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1b1/0x290 lib/dump_stack.c:106
 print_address_description+0x74/0x340 mm/kasan/report.c:306
 print_report+0x107/0x1f0 mm/kasan/report.c:417
 kasan_report+0xcd/0x100 mm/kasan/report.c:517
 ext4_ext_binsearch_idx fs/ext4/extents.c:768 [inline]
 ext4_find_extent+0x76e/0xd90 fs/ext4/extents.c:931
 ext4_clu_mapped+0x117/0x970 fs/ext4/extents.c:5809
 ext4_insert_delayed_block fs/ext4/inode.c:1696 [inline]
 ext4_da_map_blocks fs/ext4/inode.c:1806 [inline]
 ext4_da_get_block_prep+0x9e8/0x13c0 fs/ext4/inode.c:1870
 ext4_block_write_begin+0x6a8/0x2290 fs/ext4/inode.c:1098
 ext4_da_write_begin+0x539/0x760 fs/ext4/inode.c:3082
 generic_perform_write+0x2e4/0x5e0 mm/filemap.c:3772
 ext4_buffered_write_iter+0x122/0x3a0 fs/ext4/file.c:285
 ext4_file_write_iter+0x1d0/0x18f0
 call_write_iter include/linux/fs.h:2186 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x7dc/0xc50 fs/read_write.c:584
 ksys_write+0x177/0x2a0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f4b7a9737b9
RSP: 002b:00007ffc5cac3668 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f4b7a9737b9
RDX: 00000000175d9003 RSI: 0000000020000200 RDI: 0000000000000004
RBP: 00007f4b7a933050 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000079f R11: 0000000000000246 R12: 00007f4b7a9330e0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 

Above issue is happens when enable bigalloc and inline data feature. As
commit 131294c35ed6 fixed delayed allocation bug in ext4_clu_mapped for
bigalloc + inline. But it only resolved issue when has inline data, if
inline data has been converted to extent(ext4_da_convert_inline_data_to_extent)
before writepages, there is no EXT4_STATE_MAY_INLINE_DATA flag. However
i_data is still store inline data in this scene. Then will trigger UAF
when find extent.
To resolve above issue, there is need to add judge "ext4_has_inline_data(inode)"
in ext4_clu_mapped().

Fixes: 131294c35ed6 ("ext4: fix delayed allocation bug in ext4_clu_mapped for bigalloc + inline")
Reported-by: syzbot+bf4bb7731ef73b83a3b4@syzkaller.appspotmail.com
Reviewed-by: Jan Kara 
Reviewed-by: Ye Bin 
Reviewed-by: Tudor Ambarus 
Tested-by: Tudor Ambarus 
Link: https://lore.kernel.org/r/20230406111627.1916759-1-tudor.ambarus@linaro.org
Signed-off-by: Theodore Ts'o 
Signed-off-by: Sasha Levin

ext4: fix i_disksize exceeding i_size problem in paritally written case

2023-05-11T14:11:30+00:00

[ Upstream commit 1dedde690303c05ef732b7c5c8356fdf60a4ade3 ]

It is possible for i_disksize can exceed i_size, triggering a warning.

generic_perform_write
 copied = iov_iter_copy_from_user_atomic(len) // copied < len
 ext4_da_write_end
 | ext4_update_i_disksize
 |  new_i_size = pos + copied;
 |  WRITE_ONCE(EXT4_I(inode)->i_disksize, newsize) // update i_disksize
 | generic_write_end
 |  copied = block_write_end(copied, len) // copied = 0
 |   if (unlikely(copied < len))
 |    if (!PageUptodate(page))
 |     copied = 0;
 |  if (pos + copied > inode->i_size) // return false
 if (unlikely(copied == 0))
  goto again;
 if (unlikely(iov_iter_fault_in_readable(i, bytes))) {
  status = -EFAULT;
  break;
 }

We get i_disksize greater than i_size here, which could trigger WARNING
check 'i_size_read(inode) < EXT4_I(inode)->i_disksize' while doing dio:

ext4_dio_write_iter
 iomap_dio_rw
  __iomap_dio_rw // return err, length is not aligned to 512
 ext4_handle_inode_extension
  WARN_ON_ONCE(i_size_read(inode) < EXT4_I(inode)->i_disksize) // Oops

 WARNING: CPU: 2 PID: 2609 at fs/ext4/file.c:319
 CPU: 2 PID: 2609 Comm: aa Not tainted 6.3.0-rc2
 RIP: 0010:ext4_file_write_iter+0xbc7
 Call Trace:
  vfs_write+0x3b1
  ksys_write+0x77
  do_syscall_64+0x39

Fix it by updating 'copied' value before updating i_disksize just like
ext4_write_inline_data_end() does.

A reproducer can be found in the buganizer link below.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=217209
Fixes: 64769240bd07 ("ext4: Add delayed allocation support in data=writeback mode")
Signed-off-by: Zhihao Cheng 
Reviewed-by: Jan Kara 
Link: https://lore.kernel.org/r/20230321013721.89818-1-chengzhihao1@huawei.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Sasha Levin

ext4: fix possible double unlock when moving a directory

2023-03-22T12:37:57+00:00

commit 70e42feab2e20618ddd0cbfc4ab4b08628236ecd upstream.

Fixes: 0813299c586b ("ext4: Fix possible corruption when moving a directory")
Link: https://lore.kernel.org/r/5efbe1b9-ad8b-4a4f-b422-24824d2b775c@kili.mountain
Reported-by: Dan Carpenter 
Reported-by: syzbot+0c73d1d8b952c5f3d714@syzkaller.appspotmail.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

ext4: fix task hung in ext4_xattr_delete_inode

2023-03-22T12:37:56+00:00

[ Upstream commit 0f7bfd6f8164be32dbbdf36aa1e5d00485c53cd7 ]

Syzbot reported a hung task problem:
==================================================================
INFO: task syz-executor232:5073 blocked for more than 143 seconds.
      Not tainted 6.2.0-rc2-syzkaller-00024-g512dee0c00ad #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-exec232 state:D stack:21024 pid:5073 ppid:5072 flags:0x00004004
Call Trace:
 
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x995/0xe20 kernel/sched/core.c:6555
 schedule+0xcb/0x190 kernel/sched/core.c:6631
 __wait_on_freeing_inode fs/inode.c:2196 [inline]
 find_inode_fast+0x35a/0x4c0 fs/inode.c:950
 iget_locked+0xb1/0x830 fs/inode.c:1273
 __ext4_iget+0x22e/0x3ed0 fs/ext4/inode.c:4861
 ext4_xattr_inode_iget+0x68/0x4e0 fs/ext4/xattr.c:389
 ext4_xattr_inode_dec_ref_all+0x1a7/0xe50 fs/ext4/xattr.c:1148
 ext4_xattr_delete_inode+0xb04/0xcd0 fs/ext4/xattr.c:2880
 ext4_evict_inode+0xd7c/0x10b0 fs/ext4/inode.c:296
 evict+0x2a4/0x620 fs/inode.c:664
 ext4_orphan_cleanup+0xb60/0x1340 fs/ext4/orphan.c:474
 __ext4_fill_super fs/ext4/super.c:5516 [inline]
 ext4_fill_super+0x81cd/0x8700 fs/ext4/super.c:5644
 get_tree_bdev+0x400/0x620 fs/super.c:1282
 vfs_get_tree+0x88/0x270 fs/super.c:1489
 do_new_mount+0x289/0xad0 fs/namespace.c:3145
 do_mount fs/namespace.c:3488 [inline]
 __do_sys_mount fs/namespace.c:3697 [inline]
 __se_sys_mount+0x2d3/0x3c0 fs/namespace.c:3674
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fa5406fd5ea
RSP: 002b:00007ffc7232f968 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fa5406fd5ea
RDX: 0000000020000440 RSI: 0000000020000000 RDI: 00007ffc7232f970
RBP: 00007ffc7232f970 R08: 00007ffc7232f9b0 R09: 0000000000000432
R10: 0000000000804a03 R11: 0000000000000202 R12: 0000000000000004
R13: 0000555556a7a2c0 R14: 00007ffc7232f9b0 R15: 0000000000000000
 
==================================================================

The problem is that the inode contains an xattr entry with ea_inum of 15
when cleaning up an orphan inode <15>. When evict inode <15>, the reference
counting of the corresponding EA inode is decreased. When EA inode <15> is
found by find_inode_fast() in __ext4_iget(), it is found that the EA inode
holds the I_FREEING flag and waits for the EA inode to complete deletion.
As a result, when inode <15> is being deleted, we wait for inode <15> to
complete the deletion, resulting in an infinite loop and triggering Hung
Task. To solve this problem, we only need to check whether the ino of EA
inode and parent is the same before getting EA inode.

Link: https://syzkaller.appspot.com/bug?extid=77d6fcc37bbb92f26048
Reported-by: syzbot+77d6fcc37bbb92f26048@syzkaller.appspotmail.com
Signed-off-by: Baokun Li 
Reviewed-by: Jan Kara 
Link: https://lore.kernel.org/r/20230110133436.996350-1-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Sasha Levin

ext4: update s_journal_inum if it changes after journal replay

2023-03-22T12:37:56+00:00

[ Upstream commit 3039d8b8692408438a618fac2776b629852663c3 ]

When mounting a crafted ext4 image, s_journal_inum may change after journal
replay, which is obviously unreasonable because we have successfully loaded
and replayed the journal through the old s_journal_inum. And the new
s_journal_inum bypasses some of the checks in ext4_get_journal(), which
may trigger a null pointer dereference problem. So if s_journal_inum
changes after the journal replay, we ignore the change, and rewrite the
current journal_inum to the superblock.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216541
Reported-by: Luís Henriques 
Signed-off-by: Baokun Li 
Reviewed-by: Jan Kara 
Link: https://lore.kernel.org/r/20230107032126.4165860-3-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Sasha Levin

ext4: Fix deadlock during directory rename

2023-03-17T07:58:00+00:00

[ Upstream commit 3c92792da8506a295afb6d032b4476e46f979725 ]

As lockdep properly warns, we should not be locking i_rwsem while having
transactions started as the proper lock ordering used by all directory
handling operations is i_rwsem -> transaction start. Fix the lock
ordering by moving the locking of the directory earlier in
ext4_rename().

Reported-by: syzbot+9d16c39efb5fade84574@syzkaller.appspotmail.com
Fixes: 0813299c586b ("ext4: Fix possible corruption when moving a directory")
Link: https://syzkaller.appspot.com/bug?extid=9d16c39efb5fade84574
Signed-off-by: Jan Kara 
Link: https://lore.kernel.org/r/20230301141004.15087-1-jack@suse.cz
Signed-off-by: Theodore Ts'o 
Signed-off-by: Sasha Levin

ext4: Fix possible corruption when moving a directory

2023-03-17T07:57:51+00:00

[ Upstream commit 0813299c586b175d7edb25f56412c54b812d0379 ]

When we are renaming a directory to a different directory, we need to
update '..' entry in the moved directory. However nothing prevents moved
directory from being modified and even converted from the inline format
to the normal format. When such race happens the rename code gets
confused and we crash. Fix the problem by locking the moved directory.

CC: stable@vger.kernel.org
Fixes: 32f7f22c0b52 ("ext4: let ext4_rename handle inline dir")
Signed-off-by: Jan Kara 
Link: https://lore.kernel.org/r/20230126112221.11866-1-jack@suse.cz
Signed-off-by: Theodore Ts'o 
Signed-off-by: Sasha Levin

ext4: zero i_disksize when initializing the bootloader inode

2023-03-17T07:57:48+00:00

commit f5361da1e60d54ec81346aee8e3d8baf1be0b762 upstream.

If the boot loader inode has never been used before, the
EXT4_IOC_SWAP_BOOT inode will initialize it, including setting the
i_size to 0.  However, if the "never before used" boot loader has a
non-zero i_size, then i_disksize will be non-zero, and the
inconsistency between i_size and i_disksize can trigger a kernel
warning:

 WARNING: CPU: 0 PID: 2580 at fs/ext4/file.c:319
 CPU: 0 PID: 2580 Comm: bb Not tainted 6.3.0-rc1-00004-g703695902cfa
 RIP: 0010:ext4_file_write_iter+0xbc7/0xd10
 Call Trace:
  vfs_write+0x3b1/0x5c0
  ksys_write+0x77/0x160
  __x64_sys_write+0x22/0x30
  do_syscall_64+0x39/0x80

Reproducer:
 1. create corrupted image and mount it:
       mke2fs -t ext4 /tmp/foo.img 200
       debugfs -wR "sif <5> size 25700" /tmp/foo.img
       mount -t ext4 /tmp/foo.img /mnt
       cd /mnt
       echo 123 > file
 2. Run the reproducer program:
       posix_memalign(&buf, 1024, 1024)
       fd = open("file", O_RDWR | O_DIRECT);
       ioctl(fd, EXT4_IOC_SWAP_BOOT);
       write(fd, buf, 1024);

Fix this by setting i_disksize as well as i_size to zero when
initiaizing the boot loader inode.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=217159
Cc: stable@kernel.org
Signed-off-by: Zhihao Cheng 
Link: https://lore.kernel.org/r/20230308032643.641113-1-chengzhihao1@huawei.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

ext4: fix WARNING in ext4_update_inline_data

2023-03-17T07:57:48+00:00

commit 2b96b4a5d9443ca4cad58b0040be455803c05a42 upstream.

Syzbot found the following issue:
EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 without journal. Quota mode: none.
fscrypt: AES-256-CTS-CBC using implementation "cts-cbc-aes-aesni"
fscrypt: AES-256-XTS using implementation "xts-aes-aesni"
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5071 at mm/page_alloc.c:5525 __alloc_pages+0x30a/0x560 mm/page_alloc.c:5525
Modules linked in:
CPU: 1 PID: 5071 Comm: syz-executor263 Not tainted 6.2.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:__alloc_pages+0x30a/0x560 mm/page_alloc.c:5525
RSP: 0018:ffffc90003c2f1c0 EFLAGS: 00010246
RAX: ffffc90003c2f220 RBX: 0000000000000014 RCX: 0000000000000000
RDX: 0000000000000028 RSI: 0000000000000000 RDI: ffffc90003c2f248
RBP: ffffc90003c2f2d8 R08: dffffc0000000000 R09: ffffc90003c2f220
R10: fffff52000785e49 R11: 1ffff92000785e44 R12: 0000000000040d40
R13: 1ffff92000785e40 R14: dffffc0000000000 R15: 1ffff92000785e3c
FS:  0000555556c0d300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f95d5e04138 CR3: 00000000793aa000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 
 __alloc_pages_node include/linux/gfp.h:237 [inline]
 alloc_pages_node include/linux/gfp.h:260 [inline]
 __kmalloc_large_node+0x95/0x1e0 mm/slab_common.c:1113
 __do_kmalloc_node mm/slab_common.c:956 [inline]
 __kmalloc+0xfe/0x190 mm/slab_common.c:981
 kmalloc include/linux/slab.h:584 [inline]
 kzalloc include/linux/slab.h:720 [inline]
 ext4_update_inline_data+0x236/0x6b0 fs/ext4/inline.c:346
 ext4_update_inline_dir fs/ext4/inline.c:1115 [inline]
 ext4_try_add_inline_entry+0x328/0x990 fs/ext4/inline.c:1307
 ext4_add_entry+0x5a4/0xeb0 fs/ext4/namei.c:2385
 ext4_add_nondir+0x96/0x260 fs/ext4/namei.c:2772
 ext4_create+0x36c/0x560 fs/ext4/namei.c:2817
 lookup_open fs/namei.c:3413 [inline]
 open_last_lookups fs/namei.c:3481 [inline]
 path_openat+0x12ac/0x2dd0 fs/namei.c:3711
 do_filp_open+0x264/0x4f0 fs/namei.c:3741
 do_sys_openat2+0x124/0x4e0 fs/open.c:1310
 do_sys_open fs/open.c:1326 [inline]
 __do_sys_openat fs/open.c:1342 [inline]
 __se_sys_openat fs/open.c:1337 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1337
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Above issue happens as follows:
ext4_iget
   ext4_find_inline_data_nolock ->i_inline_off=164 i_inline_size=60
ext4_try_add_inline_entry
   __ext4_mark_inode_dirty
      ext4_expand_extra_isize_ea ->i_extra_isize=32 s_want_extra_isize=44
         ext4_xattr_shift_entries
	 ->after shift i_inline_off is incorrect, actually is change to 176
ext4_try_add_inline_entry
  ext4_update_inline_dir
    get_max_inline_xattr_value_size
      if (EXT4_I(inode)->i_inline_off)
	entry = (struct ext4_xattr_entry *)((void *)raw_inode +
			EXT4_I(inode)->i_inline_off);
        free += EXT4_XATTR_SIZE(le32_to_cpu(entry->e_value_size));
	->As entry is incorrect, then 'free' may be negative
   ext4_update_inline_data
      value = kzalloc(len, GFP_NOFS);
      -> len is unsigned int, maybe very large, then trigger warning when
         'kzalloc()'

To resolve the above issue we need to update 'i_inline_off' after
'ext4_xattr_shift_entries()'.  We do not need to set
EXT4_STATE_MAY_INLINE_DATA flag here, since ext4_mark_inode_dirty()
already sets this flag if needed.  Setting EXT4_STATE_MAY_INLINE_DATA
when it is needed may trigger a BUG_ON in ext4_writepages().

Reported-by: syzbot+d30838395804afc2fa6f@syzkaller.appspotmail.com
Cc: stable@kernel.org
Signed-off-by: Ye Bin 
Reviewed-by: Jan Kara 
Link: https://lore.kernel.org/r/20230307015253.2232062-3-yebin@huaweicloud.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

ext4: move where set the MAY_INLINE_DATA flag is set

2023-03-17T07:57:48+00:00

commit 1dcdce5919115a471bf4921a57f20050c545a236 upstream.

The only caller of ext4_find_inline_data_nolock() that needs setting of
EXT4_STATE_MAY_INLINE_DATA flag is ext4_iget_extra_inode().  In
ext4_write_inline_data_end() we just need to update inode->i_inline_off.
Since we are going to add one more caller that does not need to set
EXT4_STATE_MAY_INLINE_DATA, just move setting of EXT4_STATE_MAY_INLINE_DATA
out to ext4_iget_extra_inode().

Signed-off-by: Ye Bin 
Cc: stable@kernel.org
Reviewed-by: Jan Kara 
Link: https://lore.kernel.org/r/20230307015253.2232062-2-yebin@huaweicloud.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman