[syzbot] kernel BUG in ext4_ind_remove_space

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: ef6b35306dd8 Add linux-next specific files for 20220204
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=1602d71c700000
kernel config: https://syzkaller.appspot.com/x/.config?x=e0431e0b00810b4f
dashboard link: https://syzkaller.appspot.com/bug?extid=fcc629d1a1ae8d3fe8a5
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11d31674700000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+fcc629...@syzkaller.appspotmail.com

EXT4-fs warning (device sda1): ext4_block_to_path:105: block 1074791436 > max in inode 1187
------------[ cut here ]------------
kernel BUG at fs/ext4/indirect.c:1244!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 3853 Comm: syz-executor.0 Not tainted 5.17.0-rc2-next-20220204-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:ext4_ind_remove_space+0xfde/0x1400 fs/ext4/indirect.c:1244
Code: 00 0f 85 36 03 00 00 48 8b 0b 4c 89 fe 44 8b 4c 24 20 48 8b 7c 24 10 48 83 c1 04 e8 6c bb ff ff e9 02 f6 ff ff e8 12 c3 5f ff <0f> 0b 4c 8b 7c 24 50 e9 8e f9 ff ff e8 01 c3 5f ff 48 8b 7c 24 10
RSP: 0018:ffffc90003647ab8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000
RDX: ffff88807acdba80 RSI: ffffffff8218e5de RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: ffffffff8218d85a R11: 0000000000000000 R12: 0000000000001000
R13: ffffc90003647b68 R14: ffffc90003647b88 R15: ffff88806ccc2a80
FS: 00007f2b2de3d700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2961b6f090 CR3: 000000006d02e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
ext4_punch_hole+0xf3e/0x1110 fs/ext4/inode.c:4044
ext4_fallocate+0x1194/0x3ed0 fs/ext4/extents.c:4694
vfs_fallocate+0x48d/0xe10 fs/open.c:310
ksys_fallocate fs/open.c:333 [inline]
__do_sys_fallocate fs/open.c:341 [inline]
__se_sys_fallocate fs/open.c:339 [inline]
__x64_sys_fallocate+0xcf/0x140 fs/open.c:339
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f2b2e6c8059
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2b2de3d168 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007f2b2e7daf60 RCX: 00007f2b2e6c8059
RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000005
RBP: 00007f2b2e72208d R08: 0000000000000000 R09: 0000000000000000
R10: 00000ffeffeff000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffcd330bbaf R14: 00007f2b2de3d300 R15: 0000000000022000
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_ind_remove_space+0xfde/0x1400 fs/ext4/indirect.c:1244
Code: 00 0f 85 36 03 00 00 48 8b 0b 4c 89 fe 44 8b 4c 24 20 48 8b 7c 24 10 48 83 c1 04 e8 6c bb ff ff e9 02 f6 ff ff e8 12 c3 5f ff <0f> 0b 4c 8b 7c 24 50 e9 8e f9 ff ff e8 01 c3 5f ff 48 8b 7c 24 10
RSP: 0018:ffffc90003647ab8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000
RDX: ffff88807acdba80 RSI: ffffffff8218e5de RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: ffffffff8218d85a R11: 0000000000000000 R12: 0000000000001000
R13: ffffc90003647b68 R14: ffffc90003647b88 R15: ffff88806ccc2a80
FS: 00007f2b2de3d700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020200000 CR3: 000000006d02e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
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 syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
syzbot can test patches for this issue, for details see:
https://goo.gl/tpsmEJ#testing-patches

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 09688c0166e7 Linux 5.17-rc8
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11a8bd61700000
kernel config: https://syzkaller.appspot.com/x/.config?x=d35f9bc6884af6c9

dashboard link: https://syzkaller.appspot.com/bug?extid=fcc629d1a1ae8d3fe8a5
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1205b189700000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15dda4fe700000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+fcc629...@syzkaller.appspotmail.com

EXT4-fs warning (device sda1): ext4_block_to_path:105: block 1074791436 > max in inode 1137

------------[ cut here ]------------
kernel BUG at fs/ext4/indirect.c:1244!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN

CPU: 0 PID: 3590 Comm: syz-executor391 Not tainted 5.17.0-rc8-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:ext4_ind_remove_space+0xfde/0x1400 fs/ext4/indirect.c:1244

Code: 00 0f 85 36 03 00 00 48 8b 0b 4c 89 fe 44 8b 4c 24 20 48 8b 7c 24 10 48 83 c1 04 e8 3c bb ff ff e9 02 f6 ff ff e8 c2 26 66 ff <0f> 0b 4c 8b 7c 24 50 e9 8e f9 ff ff e8 b1 26 66 ff 48 8b 7c 24 10
RSP: 0018:ffffc90001adfab8 EFLAGS: 00010293

RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000

RDX: ffff888021523a00 RSI: ffffffff8212996e RDI: 0000000000000003

RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000

R10: ffffffff82128bea R11: 0000000000000000 R12: 0000000000001000
R13: ffffc90001adfb68 R14: ffffc90001adfb88 R15: ffff8880751fa088
FS: 00007f69922ff700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 0000000020000080 CR3: 0000000021605000 CR4: 0000000000350ef0
Call Trace:
<TASK>
ext4_punch_hole+0xfe8/0x11d0 fs/ext4/inode.c:4044
ext4_fallocate+0x1194/0x3ed0 fs/ext4/extents.c:4694
vfs_fallocate+0x48d/0xe10 fs/open.c:308
ksys_fallocate fs/open.c:331 [inline]
__do_sys_fallocate fs/open.c:339 [inline]
__se_sys_fallocate fs/open.c:337 [inline]
__x64_sys_fallocate+0xcf/0x140 fs/open.c:337

do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae

RIP: 0033:0x7f699234cdf9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 81 14 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:00007f69922ff308 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 0000000000000040 RCX: 00007f699234cdf9

RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000005

RBP: 00007f69923d5408 R08: 0000000000000000 R09: 0000000000000000
R10: 00000ffeffeff000 R11: 0000000000000246 R12: 00000ffeffeff000
R13: 00007f69923d5400 R14: 00007f69923a3004 R15: 0000000000022000

</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_ind_remove_space+0xfde/0x1400 fs/ext4/indirect.c:1244

Code: 00 0f 85 36 03 00 00 48 8b 0b 4c 89 fe 44 8b 4c 24 20 48 8b 7c 24 10 48 83 c1 04 e8 3c bb ff ff e9 02 f6 ff ff e8 c2 26 66 ff <0f> 0b 4c 8b 7c 24 50 e9 8e f9 ff ff e8 b1 26 66 ff 48 8b 7c 24 10
RSP: 0018:ffffc90001adfab8 EFLAGS: 00010293

RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000

RDX: ffff888021523a00 RSI: ffffffff8212996e RDI: 0000000000000003

RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000

R10: ffffffff82128bea R11: 0000000000000000 R12: 0000000000001000
R13: ffffc90001adfb68 R14: ffffc90001adfb88 R15: ffff8880751fa088
FS: 00007f69922ff700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 0000000020000080 CR3: 0000000021605000 CR4: 0000000000350ef0

[Tadeusz Struk]

#syz test:
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

===========================
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 01c9e4f743ba..dd9c35113efe 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3924,7 +3924,8 @@ int ext4_punch_hole(struct inode *inode, loff_t offset,
loff_t length)
struct super_block *sb = inode->i_sb;
ext4_lblk_t first_block, stop_block;
struct address_space *mapping = inode->i_mapping;
- loff_t first_block_offset, last_block_offset;
+ loff_t first_block_offset, last_block_offset, max_length;
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
handle_t *handle;
unsigned int credits;
int ret = 0, ret2 = 0;
@@ -3967,6 +3968,16 @@ int ext4_punch_hole(struct inode *inode, loff_t offset,
loff_t length)
offset;
}

+ /*
+ * For punch hole the length + offset needs to be at least within
+ * one block before last
+ */
+ max_length = sbi->s_bitmap_maxbytes - sbi->s_blocksize;
+ if (offset + length >= max_length) {
+ ret = -ENOSPC;
+ goto out_mutex;
+ }
+
if (offset & (sb->s_blocksize - 1) ||
(offset + length) & (sb->s_blocksize - 1)) {
/*
--
Thanks,
Tadeusz

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

failed to apply patch:
checking file fs/ext4/inode.c
patch: **** unexpected end of file in patch



Tested on:

commit: 56e337f2 Revert "gpio: Revert regression in sysfs-gpio..
git tree: upstream

dashboard link: https://syzkaller.appspot.com/bug?extid=fcc629d1a1ae8d3fe8a5
compiler:

patch: https://syzkaller.appspot.com/x/patch.diff?x=14bf8361700000

[Tadeusz Struk]

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

==============================================
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 01c9e4f743ba..355384007d11 100644

--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3924,7 +3924,8 @@ int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length)
struct super_block *sb = inode->i_sb;
ext4_lblk_t first_block, stop_block;
struct address_space *mapping = inode->i_mapping;
- loff_t first_block_offset, last_block_offset;
+ loff_t first_block_offset, last_block_offset, max_length;
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
handle_t *handle;
unsigned int credits;
int ret = 0, ret2 = 0;
@@ -3967,6 +3968,16 @@ int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length)
offset;
}

+ /*
+ * For punch hole the length + offset needs to be at least within
+ * one block before last
+ */

+ max_length = sbi->s_bitmap_maxbytes - inode->i_sb->s_blocksize;

+ if (offset + length >= max_length) {
+ ret = -ENOSPC;
+ goto out_mutex;
+ }
+
if (offset & (sb->s_blocksize - 1) ||
(offset + length) & (sb->s_blocksize - 1)) {
/*
--

2.35.1

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+fcc629...@syzkaller.appspotmail.com

Tested on:

commit: 56e337f2 Revert "gpio: Revert regression in sysfs-gpio..
git tree: upstream

kernel config: https://syzkaller.appspot.com/x/.config?x=d35f9bc6884af6c9
dashboard link: https://syzkaller.appspot.com/bug?extid=fcc629d1a1ae8d3fe8a5

compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

patch: https://syzkaller.appspot.com/x/patch.diff?x=1131f2c5700000

Note: testing is done by a robot and is best-effort only.

[Tadeusz Struk]

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+7a8060...@syzkaller.appspotmail.com

Tested on:

commit: 56e337f2 Revert "gpio: Revert regression in sysfs-gpio..

git tree: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
kernel config: https://syzkaller.appspot.com/x/.config?x=8e2dda835f422d5b
dashboard link: https://syzkaller.appspot.com/bug?extid=7a806094edd5d07ba029
compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2
patch: https://syzkaller.appspot.com/x/patch.diff?x=12e7a6d5700000

[Tadeusz Struk]

#syz test: https://android.googlesource.com/kernel/common android12-5.10

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+7a8060...@syzkaller.appspotmail.com

Tested on:

commit: 28837e41 UPSTREAM: arm64: entry: Add macro for reading..
git tree: https://android.googlesource.com/kernel/common android12-5.10
kernel config: https://syzkaller.appspot.com/x/.config?x=19aa60a59068ed72

dashboard link: https://syzkaller.appspot.com/bug?extid=7a806094edd5d07ba029
compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2

patch: https://syzkaller.appspot.com/x/patch.diff?x=13375589700000

[Jan Kara]

On Tue 15-03-22 14:38:57, Tadeusz Struk wrote:
> #syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

Did this fix fall through the cracks? Tadeusz, can you do a proper patch
submission with your Signed-off-by etc.? Thanks!

Honza

--
Jan Kara <ja...@suse.com>
SUSE Labs, CR

[Tadeusz Struk]

On 4/28/22 07:02, Jan Kara wrote:
> On Tue 15-03-22 14:38:57, Tadeusz Struk wrote:
>> #syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> Did this fix fall through the cracks? Tadeusz, can you do a proper patch
> submission with your Signed-off-by etc.? Thanks!

I'm still working on it.
--
Thanks,
Tadeusz

[syzbot]

syzbot suspects this issue was fixed by commit:

commit 2da376228a2427501feb9d15815a45dbdbdd753e
Author: Tadeusz Struk <tadeus...@linaro.org>
Date: Thu Mar 31 20:05:15 2022 +0000

ext4: limit length to bitmap_maxbytes - blocksize in punch_hole

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=100ac712f00000
start commit: 09688c0166e7 Linux 5.17-rc8

git tree: upstream
kernel config: https://syzkaller.appspot.com/x/.config?x=d35f9bc6884af6c9
dashboard link: https://syzkaller.appspot.com/bug?extid=fcc629d1a1ae8d3fe8a5

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1205b189700000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15dda4fe700000

If the result looks correct, please mark the issue as fixed by replying with:

#syz fix: ext4: limit length to bitmap_maxbytes - blocksize in punch_hole

For information about bisection process see: https://goo.gl/tpsmEJ#bisection

[syzbot]

> On Mon 09-05-22 09:41:09, syzbot wrote:
>> syzbot suspects this issue was fixed by commit:
>>
>> commit 2da376228a2427501feb9d15815a45dbdbdd753e
>> Author: Tadeusz Struk <tadeus...@linaro.org>
>> Date: Thu Mar 31 20:05:15 2022 +0000
>>
>> ext4: limit length to bitmap_maxbytes - blocksize in punch_hole
>>
>> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=100ac712f00000
>> start commit: 09688c0166e7 Linux 5.17-rc8
>> git tree: upstream
>> kernel config: https://syzkaller.appspot.com/x/.config?x=d35f9bc6884af6c9
>> dashboard link: https://syzkaller.appspot.com/bug?extid=fcc629d1a1ae8d3fe8a5
>> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1205b189700000
>> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15dda4fe700000
>>
>> If the result looks correct, please mark the issue as fixed by replying with:
>>

> Yep, looks like the same issue:

>
> #syz fix: ext4: limit length to bitmap_maxbytes - blocksize in punch_hole

Your 'fix:' command is accepted, but please keep syzkall...@googlegroups.com mailing list in CC next time. It serves as a history of what happened with each bug report. Thank you.

>
>
> Honza