linux-stable.git/fs/udf, branch linux-4.9.y

udf: Avoid double brelse() in udf_rename()

2023-01-07T11:07:30+00:00

[ Upstream commit c791730f2554a9ebb8f18df9368dc27d4ebc38c2 ]

syzbot reported a warning like below [1]:

VFS: brelse: Trying to free free buffer
WARNING: CPU: 2 PID: 7301 at fs/buffer.c:1145 __brelse+0x67/0xa0
...
Call Trace:
 
 invalidate_bh_lru+0x99/0x150
 smp_call_function_many_cond+0xe2a/0x10c0
 ? generic_remap_file_range_prep+0x50/0x50
 ? __brelse+0xa0/0xa0
 ? __mutex_lock+0x21c/0x12d0
 ? smp_call_on_cpu+0x250/0x250
 ? rcu_read_lock_sched_held+0xb/0x60
 ? lock_release+0x587/0x810
 ? __brelse+0xa0/0xa0
 ? generic_remap_file_range_prep+0x50/0x50
 on_each_cpu_cond_mask+0x3c/0x80
 blkdev_flush_mapping+0x13a/0x2f0
 blkdev_put_whole+0xd3/0xf0
 blkdev_put+0x222/0x760
 deactivate_locked_super+0x96/0x160
 deactivate_super+0xda/0x100
 cleanup_mnt+0x222/0x3d0
 task_work_run+0x149/0x240
 ? task_work_cancel+0x30/0x30
 do_exit+0xb29/0x2a40
 ? reacquire_held_locks+0x4a0/0x4a0
 ? do_raw_spin_lock+0x12a/0x2b0
 ? mm_update_next_owner+0x7c0/0x7c0
 ? rwlock_bug.part.0+0x90/0x90
 ? zap_other_threads+0x234/0x2d0
 do_group_exit+0xd0/0x2a0
 __x64_sys_exit_group+0x3a/0x50
 do_syscall_64+0x34/0xb0
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The cause of the issue is that brelse() is called on both ofibh.sbh
and ofibh.ebh by udf_find_entry() when it returns NULL.  However,
brelse() is called by udf_rename(), too.  So, b_count on buffer_head
becomes unbalanced.

This patch fixes the issue by not calling brelse() by udf_rename()
when udf_find_entry() returns NULL.

Link: https://syzkaller.appspot.com/bug?id=8297f45698159c6bca8a1f87dc983667c1a1c851 [1]
Reported-by: syzbot+7902cd7684bc35306224@syzkaller.appspotmail.com
Signed-off-by: Shigeru Yoshida 
Signed-off-by: Jan Kara 
Link: https://lore.kernel.org/r/20221023095741.271430-1-syoshida@redhat.com
Signed-off-by: Sasha Levin

udf: Fix extending file within last block

2023-01-07T11:07:11+00:00

commit 1f3868f06855c97a4954c99b36f3fc9eb8f60326 upstream.

When extending file within last block it can happen that the extent is
already rounded to the blocksize and thus contains the offset we want to
grow up to. In such case we would mistakenly expand the last extent and
make it one block longer than it should be, exposing unallocated block
in a file and causing data corruption. Fix the problem by properly
detecting this case and bailing out.

CC: stable@vger.kernel.org
Signed-off-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

udf: Do not bother looking for prealloc extents if i_lenExtents matches i_size

2023-01-07T11:07:11+00:00

commit 6ad53f0f71c52871202a7bf096feb2c59db33fc5 upstream.

If rounded block-rounded i_lenExtents matches block rounded i_size,
there are no preallocation extents. Do not bother walking extent linked
list.

CC: stable@vger.kernel.org
Signed-off-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

udf: Fix preallocation discarding at indirect extent boundary

2023-01-07T11:07:11+00:00

commit cfe4c1b25dd6d2f056afc00b7c98bcb3dd0b1fc3 upstream.

When preallocation extent is the first one in the extent block, the
code would corrupt extent tree header instead. Fix the problem and use
udf_delete_aext() for deleting extent to avoid some code duplication.

CC: stable@vger.kernel.org
Signed-off-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

udf: Drop unused arguments of udf_delete_aext()

2023-01-07T11:07:11+00:00

commit 6c1e4d06a3808dc67dbce2d631f4c12574567dd5 upstream.

udf_delete_aext() uses its last two arguments only as local variables.
Drop them.

Signed-off-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

udf: Discard preallocation before extending file with a hole

2023-01-07T11:07:10+00:00

commit 16d0556568148bdcaa45d077cac9f8f7077cf70a upstream.

When extending file with a hole, we tried to preserve existing
preallocation for the file. However that is not very useful and
complicates code because the previous extent may need to be rounded to
block boundary as well (which we forgot to do thus causing data
corruption for sequence like:

xfs_io -f -c "pwrite 0x75e63 11008" -c "truncate 0x7b24b" \
  -c "truncate 0xabaa3" -c "pwrite 0xac70b 22954" \
  -c "pwrite 0x93a43 11358" -c "pwrite 0xb8e65 52211" file

with 512-byte block size. Just discard preallocation before extending
file to simplify things and also fix this data corruption.

CC: stable@vger.kernel.org
Signed-off-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

udf: Fix a slab-out-of-bounds write bug in udf_find_entry()

2022-11-25T16:35:37+00:00

commit c8af247de385ce49afabc3bf1cf4fd455c94bfe8 upstream.

Syzbot reported a slab-out-of-bounds Write bug:

loop0: detected capacity change from 0 to 2048
==================================================================
BUG: KASAN: slab-out-of-bounds in udf_find_entry+0x8a5/0x14f0
fs/udf/namei.c:253
Write of size 105 at addr ffff8880123ff896 by task syz-executor323/3610

CPU: 0 PID: 3610 Comm: syz-executor323 Not tainted
6.1.0-rc2-syzkaller-00105-gb229b6ca5abb #0
Hardware name: Google Compute Engine/Google Compute Engine, BIOS
Google 10/11/2022
Call Trace:
 
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
 print_address_description+0x74/0x340 mm/kasan/report.c:284
 print_report+0x107/0x1f0 mm/kasan/report.c:395
 kasan_report+0xcd/0x100 mm/kasan/report.c:495
 kasan_check_range+0x2a7/0x2e0 mm/kasan/generic.c:189
 memcpy+0x3c/0x60 mm/kasan/shadow.c:66
 udf_find_entry+0x8a5/0x14f0 fs/udf/namei.c:253
 udf_lookup+0xef/0x340 fs/udf/namei.c:309
 lookup_open fs/namei.c:3391 [inline]
 open_last_lookups fs/namei.c:3481 [inline]
 path_openat+0x10e6/0x2df0 fs/namei.c:3710
 do_filp_open+0x264/0x4f0 fs/namei.c:3740
 do_sys_openat2+0x124/0x4e0 fs/open.c:1310
 do_sys_open fs/open.c:1326 [inline]
 __do_sys_creat fs/open.c:1402 [inline]
 __se_sys_creat fs/open.c:1396 [inline]
 __x64_sys_creat+0x11f/0x160 fs/open.c:1396
 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: 0033:0x7ffab0d164d9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe1a7e6bb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ffab0d164d9
RDX: 00007ffab0d164d9 RSI: 0000000000000000 RDI: 0000000020000180
RBP: 00007ffab0cd5a10 R08: 0000000000000000 R09: 0000000000000000
R10: 00005555573552c0 R11: 0000000000000246 R12: 00007ffab0cd5aa0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 

Allocated by task 3610:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x3d/0x60 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:371 [inline]
 __kasan_kmalloc+0x97/0xb0 mm/kasan/common.c:380
 kmalloc include/linux/slab.h:576 [inline]
 udf_find_entry+0x7b6/0x14f0 fs/udf/namei.c:243
 udf_lookup+0xef/0x340 fs/udf/namei.c:309
 lookup_open fs/namei.c:3391 [inline]
 open_last_lookups fs/namei.c:3481 [inline]
 path_openat+0x10e6/0x2df0 fs/namei.c:3710
 do_filp_open+0x264/0x4f0 fs/namei.c:3740
 do_sys_openat2+0x124/0x4e0 fs/open.c:1310
 do_sys_open fs/open.c:1326 [inline]
 __do_sys_creat fs/open.c:1402 [inline]
 __se_sys_creat fs/open.c:1396 [inline]
 __x64_sys_creat+0x11f/0x160 fs/open.c:1396
 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

The buggy address belongs to the object at ffff8880123ff800
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 150 bytes inside of
 256-byte region [ffff8880123ff800, ffff8880123ff900)

The buggy address belongs to the physical page:
page:ffffea000048ff80 refcount:1 mapcount:0 mapping:0000000000000000
index:0x0 pfn:0x123fe
head:ffffea000048ff80 order:1 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea00004b8500 dead000000000003 ffff888012041b40
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x0(),
pid 1, tgid 1 (swapper/0), ts 1841222404, free_ts 0
 create_dummy_stack mm/page_owner.c:67 [inline]
 register_early_stack+0x77/0xd0 mm/page_owner.c:83
 init_page_owner+0x3a/0x731 mm/page_owner.c:93
 kernel_init_freeable+0x41c/0x5d5 init/main.c:1629
 kernel_init+0x19/0x2b0 init/main.c:1519
page_owner free stack trace missing

Memory state around the buggy address:
 ffff8880123ff780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880123ff800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880123ff880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 06
                                                                ^
 ffff8880123ff900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880123ff980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Fix this by changing the memory size allocated for copy_name from
UDF_NAME_LEN(254) to UDF_NAME_LEN_CS0(255), because the total length
(lfi) of subsequent memcpy can be up to 255.

CC: stable@vger.kernel.org
Reported-by: syzbot+69c9fdccc6dd08961d34@syzkaller.appspotmail.com
Fixes: 066b9cded00b ("udf: Use separate buffer for copying split names")
Signed-off-by: ZhangPeng 
Signed-off-by: Jan Kara 
Link: https://lore.kernel.org/r/20221109013542.442790-1-zhangpeng362@huawei.com
Signed-off-by: Greg Kroah-Hartman

udf: Fix NULL ptr deref when converting from inline format

2022-02-08T17:15:26+00:00

commit 7fc3b7c2981bbd1047916ade327beccb90994eee upstream.

udf_expand_file_adinicb() calls directly ->writepage to write data
expanded into a page. This however misses to setup inode for writeback
properly and so we can crash on inode->i_wb dereference when submitting
page for IO like:

  BUG: kernel NULL pointer dereference, address: 0000000000000158
  #PF: supervisor read access in kernel mode
...
  
  __folio_start_writeback+0x2ac/0x350
  __block_write_full_page+0x37d/0x490
  udf_expand_file_adinicb+0x255/0x400 [udf]
  udf_file_write_iter+0xbe/0x1b0 [udf]
  new_sync_write+0x125/0x1c0
  vfs_write+0x28e/0x400

Fix the problem by marking the page dirty and going through the standard
writeback path to write the page. Strictly speaking we would not even
have to write the page but we want to catch e.g. ENOSPC errors early.

Reported-by: butt3rflyh4ck 
CC: stable@vger.kernel.org
Fixes: 52ebea749aae ("writeback: make backing_dev_info host cgroup-specific bdi_writebacks")
Reviewed-by: Christoph Hellwig 
Signed-off-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

udf: Restore i_lenAlloc when inode expansion fails

2022-02-08T17:15:26+00:00

commit ea8569194b43f0f01f0a84c689388542c7254a1f upstream.

When we fail to expand inode from inline format to a normal format, we
restore inode to contain the original inline formatting but we forgot to
set i_lenAlloc back. The mismatch between i_lenAlloc and i_size was then
causing further problems such as warnings and lost data down the line.

Reported-by: butt3rflyh4ck 
CC: stable@vger.kernel.org
Fixes: 7e49b6f2480c ("udf: Convert UDF to new truncate calling sequence")
Reviewed-by: Christoph Hellwig 
Signed-off-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

udf_get_extendedattr() had no boundary checks.

2021-09-22T09:42:59+00:00

[ Upstream commit 58bc6d1be2f3b0ceecb6027dfa17513ec6aa2abb ]

When parsing the ExtendedAttr data, malicous or corrupt attribute length
could cause kernel hangs and buffer overruns in some special cases.

Link: https://lore.kernel.org/r/20210822093332.25234-1-stian.skjelstad@gmail.com
Signed-off-by: Stian Skjelstad 
Signed-off-by: Jan Kara 
Signed-off-by: Sasha Levin