* [syzbot] [bcachefs?] UBSAN: shift-out-of-bounds in bch2_alloc_to_text
@ 2024-10-21 6:44 syzbot
2024-10-22 1:34 ` Hongbo Li
0 siblings, 1 reply; 3+ messages in thread
From: syzbot @ 2024-10-21 6:44 UTC (permalink / raw)
To: kent.overstreet, linux-bcachefs, linux-kernel, syzkaller-bugs
Hello,
syzbot found the following issue on:
HEAD commit: c964ced77262 Merge tag 'for-linus' of git://git.kernel.org..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12d9745f980000
kernel config: https://syzkaller.appspot.com/x/.config?x=cfbd94c114a3d407
dashboard link: https://syzkaller.appspot.com/bug?extid=7f45fa9805c40db3f108
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=12637887980000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12a1e830580000
Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-c964ced7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e937ef58569a/vmlinux-c964ced7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f1df9880ca4b/bzImage-c964ced7.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/00439b875347/mount_0.gz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7f45fa9805c40db3f108@syzkaller.appspotmail.com
bcachefs (loop0): fatal error - emergency read only
bcachefs (loop0): insufficient writeable journal devices available: have 0, need 1
rw journal devs: loop0
------------[ cut here ]------------
UBSAN: shift-out-of-bounds in fs/bcachefs/alloc_background.h:165:13
shift exponent 129 is too large for 32-bit type 'unsigned int'
CPU: 0 UID: 0 PID: 5104 Comm: syz-executor159 Not tainted 6.12.0-rc3-syzkaller-00087-gc964ced77262 #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:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
ubsan_epilogue lib/ubsan.c:231 [inline]
__ubsan_handle_shift_out_of_bounds+0x3c8/0x420 lib/ubsan.c:468
data_type_movable fs/bcachefs/alloc_background.h:165 [inline]
alloc_lru_idx_fragmentation fs/bcachefs/alloc_background.h:171 [inline]
bch2_alloc_to_text+0xc79/0xce0 fs/bcachefs/alloc_background.c:369
__bch2_bkey_fsck_err+0x1c8/0x280 fs/bcachefs/error.c:454
bch2_alloc_v4_validate+0x931/0xef0 fs/bcachefs/alloc_background.c:259
bch2_btree_node_read_done+0x3e7e/0x5e90 fs/bcachefs/btree_io.c:1223
btree_node_read_work+0x68b/0x1260 fs/bcachefs/btree_io.c:1327
bch2_btree_node_read+0x2433/0x2a10
__bch2_btree_root_read fs/bcachefs/btree_io.c:1753 [inline]
bch2_btree_root_read+0x617/0x7a0 fs/bcachefs/btree_io.c:1775
read_btree_roots+0x296/0x840 fs/bcachefs/recovery.c:524
bch2_fs_recovery+0x2585/0x39c0 fs/bcachefs/recovery.c:854
bch2_fs_start+0x356/0x5b0 fs/bcachefs/super.c:1036
bch2_fs_get_tree+0xd68/0x1710 fs/bcachefs/fs.c:2174
vfs_get_tree+0x90/0x2b0 fs/super.c:1800
do_new_mount+0x2be/0xb40 fs/namespace.c:3507
do_mount fs/namespace.c:3847 [inline]
__do_sys_mount fs/namespace.c:4055 [inline]
__se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4032
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: 0033:0x7f7b61a11dea
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 5e 04 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007ffff7f9a888 EFLAGS: 00000282 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffff7f9a8a0 RCX: 00007f7b61a11dea
RDX: 00000000200058c0 RSI: 0000000020000100 RDI: 00007ffff7f9a8a0
RBP: 0000000000000004 R08: 00007ffff7f9a8e0 R09: 00000000000058c6
R10: 0000000000000000 R11: 0000000000000282 R12: 0000000000000000
R13: 00007ffff7f9a8e0 R14: 0000000000000003 R15: 0000000001000000
</TASK>
---[ end trace ]---
---
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 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.
If you want to overwrite report's subsystems, reply with:
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(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
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If you want to undo deduplication, reply with:
#syz undup
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [syzbot] [bcachefs?] UBSAN: shift-out-of-bounds in bch2_alloc_to_text
2024-10-21 6:44 [syzbot] [bcachefs?] UBSAN: shift-out-of-bounds in bch2_alloc_to_text syzbot
@ 2024-10-22 1:34 ` Hongbo Li
2024-10-22 1:50 ` syzbot
0 siblings, 1 reply; 3+ messages in thread
From: Hongbo Li @ 2024-10-22 1:34 UTC (permalink / raw)
To: syzbot, kent.overstreet, linux-bcachefs, linux-kernel,
syzkaller-bugs
[-- Attachment #1: Type: text/plain, Size: 5000 bytes --]
#syz test:
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
c964ced77262
On 2024/10/21 14:44, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: c964ced77262 Merge tag 'for-linus' of git://git.kernel.org..
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=12d9745f980000
> kernel config: https://syzkaller.appspot.com/x/.config?x=cfbd94c114a3d407
> dashboard link: https://syzkaller.appspot.com/bug?extid=7f45fa9805c40db3f108
> 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=12637887980000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12a1e830580000
>
> Downloadable assets:
> disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-c964ced7.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/e937ef58569a/vmlinux-c964ced7.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/f1df9880ca4b/bzImage-c964ced7.xz
> mounted in repro: https://storage.googleapis.com/syzbot-assets/00439b875347/mount_0.gz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+7f45fa9805c40db3f108@syzkaller.appspotmail.com
>
> bcachefs (loop0): fatal error - emergency read only
> bcachefs (loop0): insufficient writeable journal devices available: have 0, need 1
> rw journal devs: loop0
> ------------[ cut here ]------------
> UBSAN: shift-out-of-bounds in fs/bcachefs/alloc_background.h:165:13
> shift exponent 129 is too large for 32-bit type 'unsigned int'
> CPU: 0 UID: 0 PID: 5104 Comm: syz-executor159 Not tainted 6.12.0-rc3-syzkaller-00087-gc964ced77262 #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:
> <TASK>
> __dump_stack lib/dump_stack.c:94 [inline]
> dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
> ubsan_epilogue lib/ubsan.c:231 [inline]
> __ubsan_handle_shift_out_of_bounds+0x3c8/0x420 lib/ubsan.c:468
> data_type_movable fs/bcachefs/alloc_background.h:165 [inline]
> alloc_lru_idx_fragmentation fs/bcachefs/alloc_background.h:171 [inline]
> bch2_alloc_to_text+0xc79/0xce0 fs/bcachefs/alloc_background.c:369
> __bch2_bkey_fsck_err+0x1c8/0x280 fs/bcachefs/error.c:454
> bch2_alloc_v4_validate+0x931/0xef0 fs/bcachefs/alloc_background.c:259
> bch2_btree_node_read_done+0x3e7e/0x5e90 fs/bcachefs/btree_io.c:1223
> btree_node_read_work+0x68b/0x1260 fs/bcachefs/btree_io.c:1327
> bch2_btree_node_read+0x2433/0x2a10
> __bch2_btree_root_read fs/bcachefs/btree_io.c:1753 [inline]
> bch2_btree_root_read+0x617/0x7a0 fs/bcachefs/btree_io.c:1775
> read_btree_roots+0x296/0x840 fs/bcachefs/recovery.c:524
> bch2_fs_recovery+0x2585/0x39c0 fs/bcachefs/recovery.c:854
> bch2_fs_start+0x356/0x5b0 fs/bcachefs/super.c:1036
> bch2_fs_get_tree+0xd68/0x1710 fs/bcachefs/fs.c:2174
> vfs_get_tree+0x90/0x2b0 fs/super.c:1800
> do_new_mount+0x2be/0xb40 fs/namespace.c:3507
> do_mount fs/namespace.c:3847 [inline]
> __do_sys_mount fs/namespace.c:4055 [inline]
> __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4032
> 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: 0033:0x7f7b61a11dea
> Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 5e 04 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007ffff7f9a888 EFLAGS: 00000282 ORIG_RAX: 00000000000000a5
> RAX: ffffffffffffffda RBX: 00007ffff7f9a8a0 RCX: 00007f7b61a11dea
> RDX: 00000000200058c0 RSI: 0000000020000100 RDI: 00007ffff7f9a8a0
> RBP: 0000000000000004 R08: 00007ffff7f9a8e0 R09: 00000000000058c6
> R10: 0000000000000000 R11: 0000000000000282 R12: 0000000000000000
> R13: 00007ffff7f9a8e0 R14: 0000000000000003 R15: 0000000001000000
> </TASK>
> ---[ end trace ]---
>
>
> ---
> 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 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.
>
> 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
>
[-- Attachment #2: 0001-bcachefs-Fix-shift-out-of-bounds-in-bch2_alloc_to_te.patch --]
[-- Type: text/plain, Size: 2116 bytes --]
From 17fd366091d104702af5b0699ac73b06d0b57619 Mon Sep 17 00:00:00 2001
From: Hongbo Li <lihongbo22@huawei.com>
Date: Mon, 21 Oct 2024 15:35:09 +0800
Subject: [PATCH] bcachefs: Fix shift-out-of-bounds in bch2_alloc_to_text
The syzbot found the following issue:
```
------------[ cut here ]------------
UBSAN: shift-out-of-bounds in fs/bcachefs/alloc_background.h:165:13
shift exponent 129 is too large for 32-bit type 'unsigned int'
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
ubsan_epilogue lib/ubsan.c:231 [inline]
__ubsan_handle_shift_out_of_bounds+0x3c8/0x420 lib/ubsan.c:468
data_type_movable fs/bcachefs/alloc_background.h:165 [inline]
alloc_lru_idx_fragmentation fs/bcachefs/alloc_background.h:171 [inline]
bch2_alloc_to_text+0xc79/0xce0 fs/bcachefs/alloc_background.c:369
__bch2_bkey_fsck_err+0x1c8/0x280 fs/bcachefs/error.c:454
bch2_alloc_v4_validate+0x931/0xef0 fs/bcachefs/alloc_background.c:259
...
```
In bch2_alloc_v4_validate, bcachefs doesn't check the invalid
data_type in switch-case. And this will cause shift-out-of-bounds
error for invalid data_type. This can be easily avoided by adding
the default branch in switch statement for handling the data_type.
Reported-by: syzbot+7f45fa9805c40db3f108@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=7f45fa9805c40db3f108
Fixes: 71aba590297e ("bcachefs: Always check alloc data type")
Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
---
fs/bcachefs/alloc_background.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/fs/bcachefs/alloc_background.c b/fs/bcachefs/alloc_background.c
index 6e161f8ffe8d..09ff41cac5f8 100644
--- a/fs/bcachefs/alloc_background.c
+++ b/fs/bcachefs/alloc_background.c
@@ -314,6 +314,10 @@ int bch2_alloc_v4_validate(struct bch_fs *c, struct bkey_s_c k,
break;
case BCH_DATA_stripe:
break;
+ default:
+ bkey_fsck_err_on(true, c, alloc_key_data_type_bad,
+ "unknown data type %u", a.data_type);
+ break;
}
fsck_err:
return ret;
--
2.34.1
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [syzbot] [bcachefs?] UBSAN: shift-out-of-bounds in bch2_alloc_to_text
2024-10-22 1:34 ` Hongbo Li
@ 2024-10-22 1:50 ` syzbot
0 siblings, 0 replies; 3+ messages in thread
From: syzbot @ 2024-10-22 1:50 UTC (permalink / raw)
To: kent.overstreet, lihongbo22, linux-bcachefs, linux-kernel,
syzkaller-bugs
Hello,
syzbot has tested the proposed patch but the reproducer is still triggering an issue:
UBSAN: shift-out-of-bounds in bch2_alloc_to_text
bcachefs (loop0): fatal error - emergency read only
bcachefs (loop0): insufficient writeable journal devices available: have 0, need 1
rw journal devs: loop0
------------[ cut here ]------------
UBSAN: shift-out-of-bounds in fs/bcachefs/alloc_background.h:165:13
shift exponent 129 is too large for 32-bit type 'unsigned int'
CPU: 0 UID: 0 PID: 5607 Comm: syz.0.15 Not tainted 6.12.0-rc3-syzkaller-00087-gc964ced77262-dirty #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:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
ubsan_epilogue lib/ubsan.c:231 [inline]
__ubsan_handle_shift_out_of_bounds+0x3c8/0x420 lib/ubsan.c:468
data_type_movable fs/bcachefs/alloc_background.h:165 [inline]
alloc_lru_idx_fragmentation fs/bcachefs/alloc_background.h:171 [inline]
bch2_alloc_to_text+0xc79/0xce0 fs/bcachefs/alloc_background.c:373
__bch2_bkey_fsck_err+0x1c8/0x280 fs/bcachefs/error.c:454
bch2_alloc_v4_validate+0x97b/0xf30 fs/bcachefs/alloc_background.c:259
bch2_btree_node_read_done+0x3e7e/0x5e90 fs/bcachefs/btree_io.c:1223
btree_node_read_work+0x68b/0x1260 fs/bcachefs/btree_io.c:1327
bch2_btree_node_read+0x2433/0x2a10
__bch2_btree_root_read fs/bcachefs/btree_io.c:1753 [inline]
bch2_btree_root_read+0x617/0x7a0 fs/bcachefs/btree_io.c:1775
read_btree_roots+0x296/0x840 fs/bcachefs/recovery.c:524
bch2_fs_recovery+0x2585/0x39c0 fs/bcachefs/recovery.c:854
bch2_fs_start+0x356/0x5b0 fs/bcachefs/super.c:1036
bch2_fs_get_tree+0xd68/0x1710 fs/bcachefs/fs.c:2174
vfs_get_tree+0x90/0x2b0 fs/super.c:1800
do_new_mount+0x2be/0xb40 fs/namespace.c:3507
do_mount fs/namespace.c:3847 [inline]
__do_sys_mount fs/namespace.c:4055 [inline]
__se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4032
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: 0033:0x7fca2ff7f79a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fca30df3e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fca30df3ef0 RCX: 00007fca2ff7f79a
RDX: 00000000200058c0 RSI: 0000000020000100 RDI: 00007fca30df3eb0
RBP: 00000000200058c0 R08: 00007fca30df3ef0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000020000100
R13: 00007fca30df3eb0 R14: 00000000000058cc R15: 0000000020005940
</TASK>
---[ end trace ]---
Tested on:
commit: c964ced7 Merge tag 'for-linus' of git://git.kernel.org..
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=139890a7980000
kernel config: https://syzkaller.appspot.com/x/.config?x=cfbd94c114a3d407
dashboard link: https://syzkaller.appspot.com/bug?extid=7f45fa9805c40db3f108
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch: https://syzkaller.appspot.com/x/patch.diff?x=15735c87980000
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2024-10-22 1:50 UTC | newest]
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2024-10-21 6:44 [syzbot] [bcachefs?] UBSAN: shift-out-of-bounds in bch2_alloc_to_text syzbot
2024-10-22 1:34 ` Hongbo Li
2024-10-22 1:50 ` syzbot
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