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Message-ID: <55418c89-b1b2-5aec-34d3-0dbf9510c551@kernel.org>
Date:   Tue, 11 Jul 2023 16:53:54 +0800
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Subject: Re: [f2fs-dev] [PATCH] f2fs: flush inode if atomic file is aborted
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To:     Jaegeuk Kim <jaegeuk@kernel.org>, linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net
Cc:     syzbot+e1246909d526a9d470fa@syzkaller.appspotmail.com,
        stable@vger.kernel.org
References: <20230707141142.2276510-1-jaegeuk@kernel.org>
From:   Chao Yu <chao@kernel.org>
In-Reply-To: <20230707141142.2276510-1-jaegeuk@kernel.org>
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On 2023/7/7 22:11, Jaegeuk Kim wrote:
> Let's flush the inode being aborted atomic operation to avoid stale dirty
> inode during eviction in this call stack:
> 
>    f2fs_mark_inode_dirty_sync+0x22/0x40 [f2fs]
>    f2fs_abort_atomic_write+0xc4/0xf0 [f2fs]
>    f2fs_evict_inode+0x3f/0x690 [f2fs]
>    ? sugov_start+0x140/0x140
>    evict+0xc3/0x1c0
>    evict_inodes+0x17b/0x210
>    generic_shutdown_super+0x32/0x120
>    kill_block_super+0x21/0x50
>    deactivate_locked_super+0x31/0x90
>    cleanup_mnt+0x100/0x160
>    task_work_run+0x59/0x90
>    do_exit+0x33b/0xa50
>    do_group_exit+0x2d/0x80
>    __x64_sys_exit_group+0x14/0x20
>    do_syscall_64+0x3b/0x90
>    entry_SYSCALL_64_after_hwframe+0x63/0xcd
> 
> This triggers f2fs_bug_on() in f2fs_evict_inode:
>   f2fs_bug_on(sbi, is_inode_flag_set(inode, FI_DIRTY_INODE));
> 
> This fixes the syzbot report:
> 
> loop0: detected capacity change from 0 to 131072
> F2FS-fs (loop0): invalid crc value
> F2FS-fs (loop0): Found nat_bits in checkpoint
> F2FS-fs (loop0): Mounted with checkpoint version = 48b305e4
> ------------[ cut here ]------------
> kernel BUG at fs/f2fs/inode.c:869!
> invalid opcode: 0000 [#1] PREEMPT SMP KASAN
> CPU: 0 PID: 5014 Comm: syz-executor220 Not tainted 6.4.0-syzkaller-11479-g6cd06ab12d1a #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
> RIP: 0010:f2fs_evict_inode+0x172d/0x1e00 fs/f2fs/inode.c:869
> Code: ff df 48 c1 ea 03 80 3c 02 00 0f 85 6a 06 00 00 8b 75 40 ba 01 00 00 00 4c 89 e7 e8 6d ce 06 00 e9 aa fc ff ff e8 63 22 e2 fd <0f> 0b e8 5c 22 e2 fd 48 c7 c0 a8 3a 18 8d 48 ba 00 00 00 00 00 fc
> RSP: 0018:ffffc90003a6fa00 EFLAGS: 00010293
> RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000
> RDX: ffff8880273b8000 RSI: ffffffff83a2bd0d RDI: 0000000000000007
> RBP: ffff888077db91b0 R08: 0000000000000007 R09: 0000000000000000
> R10: 0000000000000001 R11: 0000000000000001 R12: ffff888029a3c000
> R13: ffff888077db9660 R14: ffff888029a3c0b8 R15: ffff888077db9c50
> FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007f1909bb9000 CR3: 00000000276a9000 CR4: 0000000000350ef0
> Call Trace:
>   <TASK>
>   evict+0x2ed/0x6b0 fs/inode.c:665
>   dispose_list+0x117/0x1e0 fs/inode.c:698
>   evict_inodes+0x345/0x440 fs/inode.c:748
>   generic_shutdown_super+0xaf/0x480 fs/super.c:478
>   kill_block_super+0x64/0xb0 fs/super.c:1417
>   kill_f2fs_super+0x2af/0x3c0 fs/f2fs/super.c:4704
>   deactivate_locked_super+0x98/0x160 fs/super.c:330
>   deactivate_super+0xb1/0xd0 fs/super.c:361
>   cleanup_mnt+0x2ae/0x3d0 fs/namespace.c:1254
>   task_work_run+0x16f/0x270 kernel/task_work.c:179
>   exit_task_work include/linux/task_work.h:38 [inline]
>   do_exit+0xa9a/0x29a0 kernel/exit.c:874
>   do_group_exit+0xd4/0x2a0 kernel/exit.c:1024
>   __do_sys_exit_group kernel/exit.c:1035 [inline]
>   __se_sys_exit_group kernel/exit.c:1033 [inline]
>   __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1033
>   do_syscall_x64 arch/x86/entry/common.c:50 [inline]
>   do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
>   entry_SYSCALL_64_after_hwframe+0x63/0xcd
> RIP: 0033:0x7f309be71a09
> Code: Unable to access opcode bytes at 0x7f309be719df.
> RSP: 002b:00007fff171df518 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
> RAX: ffffffffffffffda RBX: 00007f309bef7330 RCX: 00007f309be71a09
> RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000001
> RBP: 0000000000000001 R08: ffffffffffffffc0 R09: 00007f309bef1e40
> R10: 0000000000010600 R11: 0000000000000246 R12: 00007f309bef7330
> R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001
>   </TASK>
> Modules linked in:
> ---[ end trace 0000000000000000 ]---
> RIP: 0010:f2fs_evict_inode+0x172d/0x1e00 fs/f2fs/inode.c:869
> Code: ff df 48 c1 ea 03 80 3c 02 00 0f 85 6a 06 00 00 8b 75 40 ba 01 00 00 00 4c 89 e7 e8 6d ce 06 00 e9 aa fc ff ff e8 63 22 e2 fd <0f> 0b e8 5c 22 e2 fd 48 c7 c0 a8 3a 18 8d 48 ba 00 00 00 00 00 fc
> RSP: 0018:ffffc90003a6fa00 EFLAGS: 00010293
> RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000
> RDX: ffff8880273b8000 RSI: ffffffff83a2bd0d RDI: 0000000000000007
> RBP: ffff888077db91b0 R08: 0000000000000007 R09: 0000000000000000
> R10: 0000000000000001 R11: 0000000000000001 R12: ffff888029a3c000
> R13: ffff888077db9660 R14: ffff888029a3c0b8 R15: ffff888077db9c50
> FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007f1909bb9000 CR3: 00000000276a9000 CR4: 0000000000350ef0
> 
> Cc: <stable@vger.kernel.org>
> Reported-by: syzbot+e1246909d526a9d470fa@syzkaller.appspotmail.com
> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Reviewed-by: Chao Yu <chao@kernel.org>

Thanks,

> ---
>   fs/f2fs/segment.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
> index 0457d620011f..6e5d1039ca76 100644
> --- a/fs/f2fs/segment.c
> +++ b/fs/f2fs/segment.c
> @@ -205,6 +205,8 @@ void f2fs_abort_atomic_write(struct inode *inode, bool clean)
>   		f2fs_i_size_write(inode, fi->original_i_size);
>   		fi->original_i_size = 0;
>   	}
> +	/* avoid stale dirty inode during eviction */
> +	sync_inode_metadata(inode, 0);
>   }
>   
>   static int __replace_atomic_write_block(struct inode *inode, pgoff_t index,