* [syzbot] [crypto?] KMSAN: uninit-value in __crc32c_le_base (4)
@ 2024-04-01 21:52 syzbot
2024-04-03 9:39 ` Herbert Xu
` (2 more replies)
0 siblings, 3 replies; 7+ messages in thread
From: syzbot @ 2024-04-01 21:52 UTC (permalink / raw)
To: davem, herbert, linux-crypto, linux-kernel, syzkaller-bugs
Hello,
syzbot found the following issue on:
HEAD commit: 8d025e2092e2 Merge tag 'erofs-for-6.9-rc2-fixes' of git://..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1385be41180000
kernel config: https://syzkaller.appspot.com/x/.config?x=e2599baf258ef795
dashboard link: https://syzkaller.appspot.com/bug?extid=549710bad9c798e25b15
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5ccde1a19e22/disk-8d025e20.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/45420817e7d9/vmlinux-8d025e20.xz
kernel image: https://storage.googleapis.com/syzbot-assets/354bdafd8c8f/bzImage-8d025e20.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+549710bad9c798e25b15@syzkaller.appspotmail.com
=====================================================
BUG: KMSAN: uninit-value in crc32_body lib/crc32.c:110 [inline]
BUG: KMSAN: uninit-value in crc32_le_generic lib/crc32.c:179 [inline]
BUG: KMSAN: uninit-value in __crc32c_le_base+0x43c/0xd80 lib/crc32.c:201
crc32_body lib/crc32.c:110 [inline]
crc32_le_generic lib/crc32.c:179 [inline]
__crc32c_le_base+0x43c/0xd80 lib/crc32.c:201
chksum_update+0x5b/0xd0 crypto/crc32c_generic.c:88
crypto_shash_update+0x79/0xa0 crypto/shash.c:70
csum_tree_block+0x35f/0x5d0 fs/btrfs/disk-io.c:96
btree_csum_one_bio+0x4d5/0xeb0 fs/btrfs/disk-io.c:294
btrfs_bio_csum fs/btrfs/bio.c:538 [inline]
btrfs_submit_chunk fs/btrfs/bio.c:741 [inline]
btrfs_submit_bio+0x1eb6/0x2930 fs/btrfs/bio.c:770
write_one_eb+0x13fa/0x1570 fs/btrfs/extent_io.c:1750
submit_eb_page fs/btrfs/extent_io.c:1909 [inline]
btree_write_cache_pages+0x1d2a/0x29a0 fs/btrfs/extent_io.c:1959
btree_writepages+0x84/0x270 fs/btrfs/disk-io.c:516
do_writepages+0x427/0xc30 mm/page-writeback.c:2612
filemap_fdatawrite_wbc+0x1d8/0x270 mm/filemap.c:397
__filemap_fdatawrite_range mm/filemap.c:430 [inline]
filemap_fdatawrite_range+0xe1/0x110 mm/filemap.c:448
btrfs_write_marked_extents+0x2e7/0x620 fs/btrfs/transaction.c:1154
btrfs_sync_log+0x9fd/0x3830 fs/btrfs/tree-log.c:2969
btrfs_sync_file+0x144c/0x1c60 fs/btrfs/file.c:1968
vfs_fsync_range+0x20d/0x270 fs/sync.c:188
generic_write_sync include/linux/fs.h:2793 [inline]
btrfs_do_write_iter+0x1c5f/0x2270 fs/btrfs/file.c:1695
btrfs_file_write_iter+0x38/0x50 fs/btrfs/file.c:1705
call_write_iter include/linux/fs.h:2108 [inline]
new_sync_write fs/read_write.c:497 [inline]
vfs_write+0xb63/0x1520 fs/read_write.c:590
ksys_write+0x20f/0x4c0 fs/read_write.c:643
__do_sys_write fs/read_write.c:655 [inline]
__se_sys_write fs/read_write.c:652 [inline]
__x64_sys_write+0x93/0xe0 fs/read_write.c:652
do_syscall_64+0xd5/0x1f0
entry_SYSCALL_64_after_hwframe+0x6d/0x75
Uninit was created at:
__alloc_pages+0x9d6/0xe70 mm/page_alloc.c:4598
__alloc_pages_bulk+0x19e/0x21e0 mm/page_alloc.c:4523
alloc_pages_bulk_array include/linux/gfp.h:202 [inline]
btrfs_alloc_page_array+0x9e/0x460 fs/btrfs/extent_io.c:689
alloc_eb_folio_array fs/btrfs/extent_io.c:724 [inline]
alloc_extent_buffer+0xa68/0x4180 fs/btrfs/extent_io.c:3859
btrfs_find_create_tree_block+0x46/0x60 fs/btrfs/disk-io.c:610
btrfs_init_new_buffer fs/btrfs/extent-tree.c:5063 [inline]
btrfs_alloc_tree_block+0x35c/0x17c0 fs/btrfs/extent-tree.c:5178
btrfs_alloc_log_tree_node fs/btrfs/disk-io.c:960 [inline]
btrfs_add_log_tree+0x1b7/0x7a0 fs/btrfs/disk-io.c:1008
start_log_trans fs/btrfs/tree-log.c:208 [inline]
btrfs_log_inode_parent+0x9b6/0x1dd0 fs/btrfs/tree-log.c:7066
btrfs_log_dentry_safe+0x9a/0x100 fs/btrfs/tree-log.c:7171
btrfs_sync_file+0x126c/0x1c60 fs/btrfs/file.c:1933
vfs_fsync_range+0x20d/0x270 fs/sync.c:188
generic_write_sync include/linux/fs.h:2793 [inline]
btrfs_do_write_iter+0x1c5f/0x2270 fs/btrfs/file.c:1695
btrfs_file_write_iter+0x38/0x50 fs/btrfs/file.c:1705
call_write_iter include/linux/fs.h:2108 [inline]
new_sync_write fs/read_write.c:497 [inline]
vfs_write+0xb63/0x1520 fs/read_write.c:590
ksys_write+0x20f/0x4c0 fs/read_write.c:643
__do_sys_write fs/read_write.c:655 [inline]
__se_sys_write fs/read_write.c:652 [inline]
__x64_sys_write+0x93/0xe0 fs/read_write.c:652
do_syscall_64+0xd5/0x1f0
entry_SYSCALL_64_after_hwframe+0x6d/0x75
CPU: 1 PID: 5344 Comm: syz-executor.4 Not tainted 6.9.0-rc1-syzkaller-00061-g8d025e2092e2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
=====================================================
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report
If you want to undo deduplication, reply with:
#syz undup
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [syzbot] [crypto?] KMSAN: uninit-value in __crc32c_le_base (4)
2024-04-01 21:52 [syzbot] [crypto?] KMSAN: uninit-value in __crc32c_le_base (4) syzbot
@ 2024-04-03 9:39 ` Herbert Xu
2024-05-09 7:22 ` [syzbot] [btrfs] " syzbot
2025-04-23 16:37 ` [PATCH] bcachefs: Fix unit-value within btree_bounce_alloc() I Hsin Cheng
2 siblings, 0 replies; 7+ messages in thread
From: Herbert Xu @ 2024-04-03 9:39 UTC (permalink / raw)
To: syzbot; +Cc: davem, linux-crypto, linux-kernel, syzkaller-bugs
#syz set subsystems: btrfs
--
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [syzbot] [btrfs] KMSAN: uninit-value in __crc32c_le_base (4)
2024-04-01 21:52 [syzbot] [crypto?] KMSAN: uninit-value in __crc32c_le_base (4) syzbot
2024-04-03 9:39 ` Herbert Xu
@ 2024-05-09 7:22 ` syzbot
2025-04-23 16:37 ` [PATCH] bcachefs: Fix unit-value within btree_bounce_alloc() I Hsin Cheng
2 siblings, 0 replies; 7+ messages in thread
From: syzbot @ 2024-05-09 7:22 UTC (permalink / raw)
To: clm, davem, dsterba, herbert, josef, linux-btrfs, linux-crypto,
linux-kernel, syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: 6d7ddd805123 Merge tag 'soc-fixes-6.9-3' of git://git.kern..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1094303f180000
kernel config: https://syzkaller.appspot.com/x/.config?x=617171361dd3cd47
dashboard link: https://syzkaller.appspot.com/bug?extid=549710bad9c798e25b15
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11047204980000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17a2905c980000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/49caca594b2f/disk-6d7ddd80.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/cad0ed0e7e81/vmlinux-6d7ddd80.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c5403827515b/bzImage-6d7ddd80.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/dfb350d62061/mount_2.gz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+549710bad9c798e25b15@syzkaller.appspotmail.com
=====================================================
BUG: KMSAN: uninit-value in crc32_body lib/crc32.c:110 [inline]
BUG: KMSAN: uninit-value in crc32_le_generic lib/crc32.c:179 [inline]
BUG: KMSAN: uninit-value in __crc32c_le_base+0x43c/0xd80 lib/crc32.c:201
crc32_body lib/crc32.c:110 [inline]
crc32_le_generic lib/crc32.c:179 [inline]
__crc32c_le_base+0x43c/0xd80 lib/crc32.c:201
chksum_update+0x5b/0xd0 crypto/crc32c_generic.c:88
crypto_shash_update+0x79/0xa0 crypto/shash.c:70
csum_tree_block+0x35f/0x5d0 fs/btrfs/disk-io.c:96
btree_csum_one_bio+0x4d5/0xeb0 fs/btrfs/disk-io.c:294
btrfs_bio_csum fs/btrfs/bio.c:538 [inline]
btrfs_submit_chunk fs/btrfs/bio.c:741 [inline]
btrfs_submit_bio+0x1eb6/0x2930 fs/btrfs/bio.c:770
write_one_eb+0x13fa/0x1570 fs/btrfs/extent_io.c:1740
submit_eb_page fs/btrfs/extent_io.c:1899 [inline]
btree_write_cache_pages+0x1d2a/0x29a0 fs/btrfs/extent_io.c:1949
btree_writepages+0x84/0x270 fs/btrfs/disk-io.c:516
do_writepages+0x427/0xc30 mm/page-writeback.c:2612
filemap_fdatawrite_wbc+0x1d8/0x270 mm/filemap.c:397
__filemap_fdatawrite_range mm/filemap.c:430 [inline]
filemap_fdatawrite_range+0xe1/0x110 mm/filemap.c:448
btrfs_write_marked_extents+0x2e7/0x620 fs/btrfs/transaction.c:1153
btrfs_sync_log+0x9fd/0x3830 fs/btrfs/tree-log.c:2969
btrfs_sync_file+0x144c/0x1c60 fs/btrfs/file.c:1968
vfs_fsync_range+0x20d/0x270 fs/sync.c:188
generic_write_sync include/linux/fs.h:2795 [inline]
btrfs_do_write_iter+0x1c5f/0x2270 fs/btrfs/file.c:1695
btrfs_file_write_iter+0x38/0x50 fs/btrfs/file.c:1705
do_iter_readv_writev+0x7e6/0x960
vfs_writev+0x574/0x1450 fs/read_write.c:971
do_writev+0x251/0x5c0 fs/read_write.c:1018
__do_sys_writev fs/read_write.c:1091 [inline]
__se_sys_writev fs/read_write.c:1088 [inline]
__x64_sys_writev+0x98/0xe0 fs/read_write.c:1088
x64_sys_call+0x23dc/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:21
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Uninit was created at:
__alloc_pages+0x9d6/0xe70 mm/page_alloc.c:4598
__alloc_pages_bulk+0x19e/0x21e0 mm/page_alloc.c:4523
alloc_pages_bulk_array include/linux/gfp.h:202 [inline]
btrfs_alloc_page_array fs/btrfs/extent_io.c:690 [inline]
alloc_eb_folio_array+0x19b/0x760 fs/btrfs/extent_io.c:714
alloc_extent_buffer+0x965/0x3ad0 fs/btrfs/extent_io.c:3849
btrfs_find_create_tree_block+0x46/0x60 fs/btrfs/disk-io.c:610
btrfs_init_new_buffer fs/btrfs/extent-tree.c:5071 [inline]
btrfs_alloc_tree_block+0x35c/0x17c0 fs/btrfs/extent-tree.c:5186
btrfs_alloc_log_tree_node fs/btrfs/disk-io.c:960 [inline]
btrfs_add_log_tree+0x1b7/0x7a0 fs/btrfs/disk-io.c:1008
start_log_trans fs/btrfs/tree-log.c:208 [inline]
btrfs_log_inode_parent+0x9b6/0x1dd0 fs/btrfs/tree-log.c:7066
btrfs_log_dentry_safe+0x9a/0x100 fs/btrfs/tree-log.c:7171
btrfs_sync_file+0x126c/0x1c60 fs/btrfs/file.c:1933
vfs_fsync_range+0x20d/0x270 fs/sync.c:188
generic_write_sync include/linux/fs.h:2795 [inline]
btrfs_do_write_iter+0x1c5f/0x2270 fs/btrfs/file.c:1695
btrfs_file_write_iter+0x38/0x50 fs/btrfs/file.c:1705
do_iter_readv_writev+0x7e6/0x960
vfs_writev+0x574/0x1450 fs/read_write.c:971
do_writev+0x251/0x5c0 fs/read_write.c:1018
__do_sys_writev fs/read_write.c:1091 [inline]
__se_sys_writev fs/read_write.c:1088 [inline]
__x64_sys_writev+0x98/0xe0 fs/read_write.c:1088
x64_sys_call+0x23dc/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:21
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
CPU: 1 PID: 5036 Comm: syz-executor761 Not tainted 6.9.0-rc7-syzkaller-00023-g6d7ddd805123 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
=====================================================
---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH] bcachefs: Fix unit-value within btree_bounce_alloc()
2024-04-01 21:52 [syzbot] [crypto?] KMSAN: uninit-value in __crc32c_le_base (4) syzbot
2024-04-03 9:39 ` Herbert Xu
2024-05-09 7:22 ` [syzbot] [btrfs] " syzbot
@ 2025-04-23 16:37 ` I Hsin Cheng
2025-04-23 16:45 ` Kent Overstreet
2 siblings, 1 reply; 7+ messages in thread
From: I Hsin Cheng @ 2025-04-23 16:37 UTC (permalink / raw)
To: syzbot+549710bad9c798e25b15, kent.overstreet
Cc: bfoster, linux-bcachefs, linux-kernel, davem, herbert,
linux-crypto, syzkaller-bugs, skhan, linux-kernel-mentees,
I Hsin Cheng
Use "kvzalloc()" instead of "kvmalloc()" in btree_bounce_alloc() to
prevent uninit-value issue.
Reported-by: syzbot+549710bad9c798e25b15@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=549710bad9c798e25b15
Fixes: cb6fc943b650 ("bcachefs: kill kvpmalloc()")
Signed-off-by: I Hsin Cheng <richard120310@gmail.com>
---
syzbot reported an uninit-value issue. [1]
Though the uninit value was detected in the context of crc32_body(), the
memory was actually allocated in "btree_bounce_alloc()". Use
"kvzalloc()" to allocate the memory can solve the issue, and I've tested
against syzbot. [2]
If there're any further tests needed to be performed, please let me
know. I'll be more than happy to assist you with that, thanks !
[1]:
BUG: KMSAN: uninit-value in crc32_body lib/crc32.c:110 [inline]
BUG: KMSAN: uninit-value in crc32_le_generic lib/crc32.c:179 [inline]
BUG: KMSAN: uninit-value in __crc32c_le_base+0x43c/0xd80 lib/crc32.c:201
crc32_body lib/crc32.c:110 [inline]
crc32_le_generic lib/crc32.c:179 [inline]
__crc32c_le_base+0x43c/0xd80 lib/crc32.c:201
chksum_update+0x5b/0xd0 crypto/crc32c_generic.c:88
crypto_shash_update+0x79/0xa0 crypto/shash.c:52
crc32c+0xba/0x170 lib/libcrc32c.c:47
bch2_checksum_update+0x106/0x1d0 fs/bcachefs/checksum.c:83
bch2_checksum+0x3c5/0x7c0 fs/bcachefs/checksum.c:216
__bch2_btree_node_write+0x528c/0x67c0 fs/bcachefs/btree_io.c:2151
bch2_btree_node_write+0xa5/0x2e0 fs/bcachefs/btree_io.c:2288
btree_node_write_if_need fs/bcachefs/btree_io.h:153 [inline]
__btree_node_flush+0x4d0/0x640 fs/bcachefs/btree_trans_commit.c:229
bch2_btree_node_flush0+0x35/0x60 fs/bcachefs/btree_trans_commit.c:238
journal_flush_pins+0xce6/0x1780 fs/bcachefs/journal_reclaim.c:553
__bch2_journal_reclaim+0xd88/0x1610 fs/bcachefs/journal_reclaim.c:685
bch2_journal_reclaim_thread+0x18e/0x760 fs/bcachefs/journal_reclaim.c:727
kthread+0x3e2/0x540 kernel/kthread.c:389
ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Uninit was stored to memory at:
memcpy_u64s_small fs/bcachefs/util.h:511 [inline]
bkey_p_copy fs/bcachefs/bkey.h:46 [inline]
bch2_sort_keys+0x1b4d/0x2cb0 fs/bcachefs/bkey_sort.c:194
__bch2_btree_node_write+0x3acd/0x67c0 fs/bcachefs/btree_io.c:2100
bch2_btree_node_write+0xa5/0x2e0 fs/bcachefs/btree_io.c:2288
btree_node_write_if_need fs/bcachefs/btree_io.h:153 [inline]
__btree_node_flush+0x4d0/0x640 fs/bcachefs/btree_trans_commit.c:229
bch2_btree_node_flush0+0x35/0x60 fs/bcachefs/btree_trans_commit.c:238
journal_flush_pins+0xce6/0x1780 fs/bcachefs/journal_reclaim.c:553
__bch2_journal_reclaim+0xd88/0x1610 fs/bcachefs/journal_reclaim.c:685
bch2_journal_reclaim_thread+0x18e/0x760 fs/bcachefs/journal_reclaim.c:727
kthread+0x3e2/0x540 kernel/kthread.c:389
ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Uninit was created at:
__kmalloc_large_node+0x231/0x370 mm/slub.c:3994
__do_kmalloc_node mm/slub.c:4027 [inline]
__kmalloc_node+0xb10/0x10c0 mm/slub.c:4046
kmalloc_node include/linux/slab.h:648 [inline]
kvmalloc_node+0xc0/0x2d0 mm/util.c:634
kvmalloc include/linux/slab.h:766 [inline]
btree_bounce_alloc fs/bcachefs/btree_io.c:118 [inline]
bch2_btree_node_read_done+0x4e68/0x75e0 fs/bcachefs/btree_io.c:1185
btree_node_read_work+0x8a5/0x1eb0 fs/bcachefs/btree_io.c:1324
bch2_btree_node_read+0x3d42/0x4b50
__bch2_btree_root_read fs/bcachefs/btree_io.c:1748 [inline]
bch2_btree_root_read+0xa6c/0x13d0 fs/bcachefs/btree_io.c:1772
read_btree_roots+0x454/0xee0 fs/bcachefs/recovery.c:457
bch2_fs_recovery+0x7b6a/0x93e0 fs/bcachefs/recovery.c:785
bch2_fs_start+0x7b2/0xbd0 fs/bcachefs/super.c:1043
bch2_fs_open+0x152a/0x15f0 fs/bcachefs/super.c:2105
bch2_mount+0x90d/0x1d90 fs/bcachefs/fs.c:1906
legacy_get_tree+0x114/0x290 fs/fs_context.c:662
vfs_get_tree+0xa7/0x570 fs/super.c:1779
do_new_mount+0x71f/0x15e0 fs/namespace.c:3352
path_mount+0x742/0x1f20 fs/namespace.c:3679
do_mount fs/namespace.c:3692 [inline]
__do_sys_mount fs/namespace.c:3898 [inline]
__se_sys_mount+0x725/0x810 fs/namespace.c:3875
__x64_sys_mount+0xe4/0x150 fs/namespace.c:3875
x64_sys_call+0x2bf4/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:166
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
[2]:
https://lore.kernel.org/all/000000000000736bd406151001d7@google.com/T/#m748384a36239a7f66e63cfde949e3db6bf14d5c6
syzbot reply me with:
Hello,
syzbot has tested the proposed patch and the reproducer did not trigger any issue:
Reported-by: syzbot+549710bad9c798e25b15@syzkaller.appspotmail.com
Tested-by: syzbot+549710bad9c798e25b15@syzkaller.appspotmail.com
Tested on:
commit: 614da38e Merge tag 'hid-for-linus-2024051401' of git:/..
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=10be763f980000
kernel config: https://syzkaller.appspot.com/x/.config?x=49342144b6a907af
dashboard link: https://syzkaller.appspot.com/bug?extid=549710bad9c798e25b15
compiler: Debian clang version 15.0.6, Debian LLD 15.0.6
patch: https://syzkaller.appspot.com/x/patch.diff?x=15b99a6f980000
Note: testing is done by a robot and is best-effort only.
Best regards,
I Hsin Cheng
---
fs/bcachefs/btree_io.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/bcachefs/btree_io.c b/fs/bcachefs/btree_io.c
index debb0edc3455..dc00c5273ffe 100644
--- a/fs/bcachefs/btree_io.c
+++ b/fs/bcachefs/btree_io.c
@@ -115,7 +115,7 @@ static void *btree_bounce_alloc(struct bch_fs *c, size_t size,
BUG_ON(size > c->opts.btree_node_size);
*used_mempool = false;
- p = kvmalloc(size, __GFP_NOWARN|GFP_NOWAIT);
+ p = kvzalloc(size, __GFP_NOWARN|GFP_NOWAIT);
if (!p) {
*used_mempool = true;
p = mempool_alloc(&c->btree_bounce_pool, GFP_NOFS);
--
2.43.0
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH] bcachefs: Fix unit-value within btree_bounce_alloc()
2025-04-23 16:37 ` [PATCH] bcachefs: Fix unit-value within btree_bounce_alloc() I Hsin Cheng
@ 2025-04-23 16:45 ` Kent Overstreet
2025-04-25 16:53 ` I Hsin Cheng
0 siblings, 1 reply; 7+ messages in thread
From: Kent Overstreet @ 2025-04-23 16:45 UTC (permalink / raw)
To: I Hsin Cheng
Cc: syzbot+549710bad9c798e25b15, bfoster, linux-bcachefs,
linux-kernel, davem, herbert, linux-crypto, syzkaller-bugs, skhan,
linux-kernel-mentees
On Thu, Apr 24, 2025 at 12:37:18AM +0800, I Hsin Cheng wrote:
> Use "kvzalloc()" instead of "kvmalloc()" in btree_bounce_alloc() to
> prevent uninit-value issue.
>
> Reported-by: syzbot+549710bad9c798e25b15@syzkaller.appspotmail.com
> Closes: https://syzkaller.appspot.com/bug?extid=549710bad9c798e25b15
> Fixes: cb6fc943b650 ("bcachefs: kill kvpmalloc()")
> Signed-off-by: I Hsin Cheng <richard120310@gmail.com>
> ---
> syzbot reported an uninit-value issue. [1]
>
> Though the uninit value was detected in the context of crc32_body(), the
> memory was actually allocated in "btree_bounce_alloc()". Use
> "kvzalloc()" to allocate the memory can solve the issue, and I've tested
> against syzbot. [2]
>
> If there're any further tests needed to be performed, please let me
> know. I'll be more than happy to assist you with that, thanks !
See Documentation/filesystems/bcachefs/SubmittingPatches.
And this isn't the correct fix - the correct fix is already in Linus's
tree.
>
> [1]:
> BUG: KMSAN: uninit-value in crc32_body lib/crc32.c:110 [inline]
> BUG: KMSAN: uninit-value in crc32_le_generic lib/crc32.c:179 [inline]
> BUG: KMSAN: uninit-value in __crc32c_le_base+0x43c/0xd80 lib/crc32.c:201
> crc32_body lib/crc32.c:110 [inline]
> crc32_le_generic lib/crc32.c:179 [inline]
> __crc32c_le_base+0x43c/0xd80 lib/crc32.c:201
> chksum_update+0x5b/0xd0 crypto/crc32c_generic.c:88
> crypto_shash_update+0x79/0xa0 crypto/shash.c:52
> crc32c+0xba/0x170 lib/libcrc32c.c:47
> bch2_checksum_update+0x106/0x1d0 fs/bcachefs/checksum.c:83
> bch2_checksum+0x3c5/0x7c0 fs/bcachefs/checksum.c:216
> __bch2_btree_node_write+0x528c/0x67c0 fs/bcachefs/btree_io.c:2151
> bch2_btree_node_write+0xa5/0x2e0 fs/bcachefs/btree_io.c:2288
> btree_node_write_if_need fs/bcachefs/btree_io.h:153 [inline]
> __btree_node_flush+0x4d0/0x640 fs/bcachefs/btree_trans_commit.c:229
> bch2_btree_node_flush0+0x35/0x60 fs/bcachefs/btree_trans_commit.c:238
> journal_flush_pins+0xce6/0x1780 fs/bcachefs/journal_reclaim.c:553
> __bch2_journal_reclaim+0xd88/0x1610 fs/bcachefs/journal_reclaim.c:685
> bch2_journal_reclaim_thread+0x18e/0x760 fs/bcachefs/journal_reclaim.c:727
> kthread+0x3e2/0x540 kernel/kthread.c:389
> ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
> ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
>
> Uninit was stored to memory at:
> memcpy_u64s_small fs/bcachefs/util.h:511 [inline]
> bkey_p_copy fs/bcachefs/bkey.h:46 [inline]
> bch2_sort_keys+0x1b4d/0x2cb0 fs/bcachefs/bkey_sort.c:194
> __bch2_btree_node_write+0x3acd/0x67c0 fs/bcachefs/btree_io.c:2100
> bch2_btree_node_write+0xa5/0x2e0 fs/bcachefs/btree_io.c:2288
> btree_node_write_if_need fs/bcachefs/btree_io.h:153 [inline]
> __btree_node_flush+0x4d0/0x640 fs/bcachefs/btree_trans_commit.c:229
> bch2_btree_node_flush0+0x35/0x60 fs/bcachefs/btree_trans_commit.c:238
> journal_flush_pins+0xce6/0x1780 fs/bcachefs/journal_reclaim.c:553
> __bch2_journal_reclaim+0xd88/0x1610 fs/bcachefs/journal_reclaim.c:685
> bch2_journal_reclaim_thread+0x18e/0x760 fs/bcachefs/journal_reclaim.c:727
> kthread+0x3e2/0x540 kernel/kthread.c:389
> ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
> ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
>
> Uninit was created at:
> __kmalloc_large_node+0x231/0x370 mm/slub.c:3994
> __do_kmalloc_node mm/slub.c:4027 [inline]
> __kmalloc_node+0xb10/0x10c0 mm/slub.c:4046
> kmalloc_node include/linux/slab.h:648 [inline]
> kvmalloc_node+0xc0/0x2d0 mm/util.c:634
> kvmalloc include/linux/slab.h:766 [inline]
> btree_bounce_alloc fs/bcachefs/btree_io.c:118 [inline]
> bch2_btree_node_read_done+0x4e68/0x75e0 fs/bcachefs/btree_io.c:1185
> btree_node_read_work+0x8a5/0x1eb0 fs/bcachefs/btree_io.c:1324
> bch2_btree_node_read+0x3d42/0x4b50
> __bch2_btree_root_read fs/bcachefs/btree_io.c:1748 [inline]
> bch2_btree_root_read+0xa6c/0x13d0 fs/bcachefs/btree_io.c:1772
> read_btree_roots+0x454/0xee0 fs/bcachefs/recovery.c:457
> bch2_fs_recovery+0x7b6a/0x93e0 fs/bcachefs/recovery.c:785
> bch2_fs_start+0x7b2/0xbd0 fs/bcachefs/super.c:1043
> bch2_fs_open+0x152a/0x15f0 fs/bcachefs/super.c:2105
> bch2_mount+0x90d/0x1d90 fs/bcachefs/fs.c:1906
> legacy_get_tree+0x114/0x290 fs/fs_context.c:662
> vfs_get_tree+0xa7/0x570 fs/super.c:1779
> do_new_mount+0x71f/0x15e0 fs/namespace.c:3352
> path_mount+0x742/0x1f20 fs/namespace.c:3679
> do_mount fs/namespace.c:3692 [inline]
> __do_sys_mount fs/namespace.c:3898 [inline]
> __se_sys_mount+0x725/0x810 fs/namespace.c:3875
> __x64_sys_mount+0xe4/0x150 fs/namespace.c:3875
> x64_sys_call+0x2bf4/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:166
> do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
>
> [2]:
> https://lore.kernel.org/all/000000000000736bd406151001d7@google.com/T/#m748384a36239a7f66e63cfde949e3db6bf14d5c6
>
> syzbot reply me with:
> Hello,
>
> syzbot has tested the proposed patch and the reproducer did not trigger any issue:
>
> Reported-by: syzbot+549710bad9c798e25b15@syzkaller.appspotmail.com
> Tested-by: syzbot+549710bad9c798e25b15@syzkaller.appspotmail.com
>
> Tested on:
>
> commit: 614da38e Merge tag 'hid-for-linus-2024051401' of git:/..
> git tree: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> console output: https://syzkaller.appspot.com/x/log.txt?x=10be763f980000
> kernel config: https://syzkaller.appspot.com/x/.config?x=49342144b6a907af
> dashboard link: https://syzkaller.appspot.com/bug?extid=549710bad9c798e25b15
> compiler: Debian clang version 15.0.6, Debian LLD 15.0.6
> patch: https://syzkaller.appspot.com/x/patch.diff?x=15b99a6f980000
>
> Note: testing is done by a robot and is best-effort only.
>
> Best regards,
> I Hsin Cheng
> ---
> fs/bcachefs/btree_io.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/bcachefs/btree_io.c b/fs/bcachefs/btree_io.c
> index debb0edc3455..dc00c5273ffe 100644
> --- a/fs/bcachefs/btree_io.c
> +++ b/fs/bcachefs/btree_io.c
> @@ -115,7 +115,7 @@ static void *btree_bounce_alloc(struct bch_fs *c, size_t size,
> BUG_ON(size > c->opts.btree_node_size);
>
> *used_mempool = false;
> - p = kvmalloc(size, __GFP_NOWARN|GFP_NOWAIT);
> + p = kvzalloc(size, __GFP_NOWARN|GFP_NOWAIT);
> if (!p) {
> *used_mempool = true;
> p = mempool_alloc(&c->btree_bounce_pool, GFP_NOFS);
> --
> 2.43.0
>
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] bcachefs: Fix unit-value within btree_bounce_alloc()
2025-04-23 16:45 ` Kent Overstreet
@ 2025-04-25 16:53 ` I Hsin Cheng
2025-04-26 15:03 ` Kent Overstreet
0 siblings, 1 reply; 7+ messages in thread
From: I Hsin Cheng @ 2025-04-25 16:53 UTC (permalink / raw)
To: Kent Overstreet
Cc: syzbot+549710bad9c798e25b15, bfoster, linux-bcachefs,
linux-kernel, davem, herbert, linux-crypto, syzkaller-bugs, skhan,
linux-kernel-mentees
On Wed, Apr 23, 2025 at 12:45:20PM -0400, Kent Overstreet wrote:
> On Thu, Apr 24, 2025 at 12:37:18AM +0800, I Hsin Cheng wrote:
> > Use "kvzalloc()" instead of "kvmalloc()" in btree_bounce_alloc() to
> > prevent uninit-value issue.
> >
> > Reported-by: syzbot+549710bad9c798e25b15@syzkaller.appspotmail.com
> > Closes: https://syzkaller.appspot.com/bug?extid=549710bad9c798e25b15
> > Fixes: cb6fc943b650 ("bcachefs: kill kvpmalloc()")
> > Signed-off-by: I Hsin Cheng <richard120310@gmail.com>
> > ---
> > syzbot reported an uninit-value issue. [1]
> >
> > Though the uninit value was detected in the context of crc32_body(), the
> > memory was actually allocated in "btree_bounce_alloc()". Use
> > "kvzalloc()" to allocate the memory can solve the issue, and I've tested
> > against syzbot. [2]
> >
> > If there're any further tests needed to be performed, please let me
> > know. I'll be more than happy to assist you with that, thanks !
>
> See Documentation/filesystems/bcachefs/SubmittingPatches.
>
Sure ! Thanks for the info.
> And this isn't the correct fix - the correct fix is already in Linus's
> tree.
Ahh ok, may I ask for the commit hash or title so I can learn from it ?
Best regards,
I Hsin Cheng
>
> >
> > [1]:
> > BUG: KMSAN: uninit-value in crc32_body lib/crc32.c:110 [inline]
> > BUG: KMSAN: uninit-value in crc32_le_generic lib/crc32.c:179 [inline]
> > BUG: KMSAN: uninit-value in __crc32c_le_base+0x43c/0xd80 lib/crc32.c:201
> > crc32_body lib/crc32.c:110 [inline]
> > crc32_le_generic lib/crc32.c:179 [inline]
> > __crc32c_le_base+0x43c/0xd80 lib/crc32.c:201
> > chksum_update+0x5b/0xd0 crypto/crc32c_generic.c:88
> > crypto_shash_update+0x79/0xa0 crypto/shash.c:52
> > crc32c+0xba/0x170 lib/libcrc32c.c:47
> > bch2_checksum_update+0x106/0x1d0 fs/bcachefs/checksum.c:83
> > bch2_checksum+0x3c5/0x7c0 fs/bcachefs/checksum.c:216
> > __bch2_btree_node_write+0x528c/0x67c0 fs/bcachefs/btree_io.c:2151
> > bch2_btree_node_write+0xa5/0x2e0 fs/bcachefs/btree_io.c:2288
> > btree_node_write_if_need fs/bcachefs/btree_io.h:153 [inline]
> > __btree_node_flush+0x4d0/0x640 fs/bcachefs/btree_trans_commit.c:229
> > bch2_btree_node_flush0+0x35/0x60 fs/bcachefs/btree_trans_commit.c:238
> > journal_flush_pins+0xce6/0x1780 fs/bcachefs/journal_reclaim.c:553
> > __bch2_journal_reclaim+0xd88/0x1610 fs/bcachefs/journal_reclaim.c:685
> > bch2_journal_reclaim_thread+0x18e/0x760 fs/bcachefs/journal_reclaim.c:727
> > kthread+0x3e2/0x540 kernel/kthread.c:389
> > ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
> > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
> >
> > Uninit was stored to memory at:
> > memcpy_u64s_small fs/bcachefs/util.h:511 [inline]
> > bkey_p_copy fs/bcachefs/bkey.h:46 [inline]
> > bch2_sort_keys+0x1b4d/0x2cb0 fs/bcachefs/bkey_sort.c:194
> > __bch2_btree_node_write+0x3acd/0x67c0 fs/bcachefs/btree_io.c:2100
> > bch2_btree_node_write+0xa5/0x2e0 fs/bcachefs/btree_io.c:2288
> > btree_node_write_if_need fs/bcachefs/btree_io.h:153 [inline]
> > __btree_node_flush+0x4d0/0x640 fs/bcachefs/btree_trans_commit.c:229
> > bch2_btree_node_flush0+0x35/0x60 fs/bcachefs/btree_trans_commit.c:238
> > journal_flush_pins+0xce6/0x1780 fs/bcachefs/journal_reclaim.c:553
> > __bch2_journal_reclaim+0xd88/0x1610 fs/bcachefs/journal_reclaim.c:685
> > bch2_journal_reclaim_thread+0x18e/0x760 fs/bcachefs/journal_reclaim.c:727
> > kthread+0x3e2/0x540 kernel/kthread.c:389
> > ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
> > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
> >
> > Uninit was created at:
> > __kmalloc_large_node+0x231/0x370 mm/slub.c:3994
> > __do_kmalloc_node mm/slub.c:4027 [inline]
> > __kmalloc_node+0xb10/0x10c0 mm/slub.c:4046
> > kmalloc_node include/linux/slab.h:648 [inline]
> > kvmalloc_node+0xc0/0x2d0 mm/util.c:634
> > kvmalloc include/linux/slab.h:766 [inline]
> > btree_bounce_alloc fs/bcachefs/btree_io.c:118 [inline]
> > bch2_btree_node_read_done+0x4e68/0x75e0 fs/bcachefs/btree_io.c:1185
> > btree_node_read_work+0x8a5/0x1eb0 fs/bcachefs/btree_io.c:1324
> > bch2_btree_node_read+0x3d42/0x4b50
> > __bch2_btree_root_read fs/bcachefs/btree_io.c:1748 [inline]
> > bch2_btree_root_read+0xa6c/0x13d0 fs/bcachefs/btree_io.c:1772
> > read_btree_roots+0x454/0xee0 fs/bcachefs/recovery.c:457
> > bch2_fs_recovery+0x7b6a/0x93e0 fs/bcachefs/recovery.c:785
> > bch2_fs_start+0x7b2/0xbd0 fs/bcachefs/super.c:1043
> > bch2_fs_open+0x152a/0x15f0 fs/bcachefs/super.c:2105
> > bch2_mount+0x90d/0x1d90 fs/bcachefs/fs.c:1906
> > legacy_get_tree+0x114/0x290 fs/fs_context.c:662
> > vfs_get_tree+0xa7/0x570 fs/super.c:1779
> > do_new_mount+0x71f/0x15e0 fs/namespace.c:3352
> > path_mount+0x742/0x1f20 fs/namespace.c:3679
> > do_mount fs/namespace.c:3692 [inline]
> > __do_sys_mount fs/namespace.c:3898 [inline]
> > __se_sys_mount+0x725/0x810 fs/namespace.c:3875
> > __x64_sys_mount+0xe4/0x150 fs/namespace.c:3875
> > x64_sys_call+0x2bf4/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:166
> > do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> > do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
> > entry_SYSCALL_64_after_hwframe+0x77/0x7f
> >
> > [2]:
> > https://lore.kernel.org/all/000000000000736bd406151001d7@google.com/T/#m748384a36239a7f66e63cfde949e3db6bf14d5c6
> >
> > syzbot reply me with:
> > Hello,
> >
> > syzbot has tested the proposed patch and the reproducer did not trigger any issue:
> >
> > Reported-by: syzbot+549710bad9c798e25b15@syzkaller.appspotmail.com
> > Tested-by: syzbot+549710bad9c798e25b15@syzkaller.appspotmail.com
> >
> > Tested on:
> >
> > commit: 614da38e Merge tag 'hid-for-linus-2024051401' of git:/..
> > git tree: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> > console output: https://syzkaller.appspot.com/x/log.txt?x=10be763f980000
> > kernel config: https://syzkaller.appspot.com/x/.config?x=49342144b6a907af
> > dashboard link: https://syzkaller.appspot.com/bug?extid=549710bad9c798e25b15
> > compiler: Debian clang version 15.0.6, Debian LLD 15.0.6
> > patch: https://syzkaller.appspot.com/x/patch.diff?x=15b99a6f980000
> >
> > Note: testing is done by a robot and is best-effort only.
> >
> > Best regards,
> > I Hsin Cheng
> > ---
> > fs/bcachefs/btree_io.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/fs/bcachefs/btree_io.c b/fs/bcachefs/btree_io.c
> > index debb0edc3455..dc00c5273ffe 100644
> > --- a/fs/bcachefs/btree_io.c
> > +++ b/fs/bcachefs/btree_io.c
> > @@ -115,7 +115,7 @@ static void *btree_bounce_alloc(struct bch_fs *c, size_t size,
> > BUG_ON(size > c->opts.btree_node_size);
> >
> > *used_mempool = false;
> > - p = kvmalloc(size, __GFP_NOWARN|GFP_NOWAIT);
> > + p = kvzalloc(size, __GFP_NOWARN|GFP_NOWAIT);
> > if (!p) {
> > *used_mempool = true;
> > p = mempool_alloc(&c->btree_bounce_pool, GFP_NOFS);
> > --
> > 2.43.0
> >
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] bcachefs: Fix unit-value within btree_bounce_alloc()
2025-04-25 16:53 ` I Hsin Cheng
@ 2025-04-26 15:03 ` Kent Overstreet
0 siblings, 0 replies; 7+ messages in thread
From: Kent Overstreet @ 2025-04-26 15:03 UTC (permalink / raw)
To: I Hsin Cheng
Cc: syzbot+549710bad9c798e25b15, bfoster, linux-bcachefs,
linux-kernel, davem, herbert, linux-crypto, syzkaller-bugs, skhan,
linux-kernel-mentees
On Sat, Apr 26, 2025 at 12:53:49AM +0800, I Hsin Cheng wrote:
> On Wed, Apr 23, 2025 at 12:45:20PM -0400, Kent Overstreet wrote:
> > On Thu, Apr 24, 2025 at 12:37:18AM +0800, I Hsin Cheng wrote:
> > > Use "kvzalloc()" instead of "kvmalloc()" in btree_bounce_alloc() to
> > > prevent uninit-value issue.
> > >
> > > Reported-by: syzbot+549710bad9c798e25b15@syzkaller.appspotmail.com
> > > Closes: https://syzkaller.appspot.com/bug?extid=549710bad9c798e25b15
> > > Fixes: cb6fc943b650 ("bcachefs: kill kvpmalloc()")
> > > Signed-off-by: I Hsin Cheng <richard120310@gmail.com>
> > > ---
> > > syzbot reported an uninit-value issue. [1]
> > >
> > > Though the uninit value was detected in the context of crc32_body(), the
> > > memory was actually allocated in "btree_bounce_alloc()". Use
> > > "kvzalloc()" to allocate the memory can solve the issue, and I've tested
> > > against syzbot. [2]
> > >
> > > If there're any further tests needed to be performed, please let me
> > > know. I'll be more than happy to assist you with that, thanks !
> >
> > See Documentation/filesystems/bcachefs/SubmittingPatches.
> >
>
> Sure ! Thanks for the info.
>
> > And this isn't the correct fix - the correct fix is already in Linus's
> > tree.
>
> Ahh ok, may I ask for the commit hash or title so I can learn from it ?
9c3a2c9b471a bcachefs: Disable asm memcpys when kmsan enabled
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2024-04-01 21:52 [syzbot] [crypto?] KMSAN: uninit-value in __crc32c_le_base (4) syzbot
2024-04-03 9:39 ` Herbert Xu
2024-05-09 7:22 ` [syzbot] [btrfs] " syzbot
2025-04-23 16:37 ` [PATCH] bcachefs: Fix unit-value within btree_bounce_alloc() I Hsin Cheng
2025-04-23 16:45 ` Kent Overstreet
2025-04-25 16:53 ` I Hsin Cheng
2025-04-26 15:03 ` Kent Overstreet
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