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Message-ID: <97b16883-64ec-ba32-ddf2-656ff7a5fc80@kernel.org>
Date:   Tue, 7 Feb 2023 20:35:38 +0800
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Subject: Re: [f2fs-dev] [PATCH] f2fs: fix kernel crash due to null io->bio
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To:     Jaegeuk Kim <jaegeuk@kernel.org>, linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net
Cc:     stable@vger.kernel.org
References: <20230206034344.724593-1-jaegeuk@kernel.org>
From:   Chao Yu <chao@kernel.org>
In-Reply-To: <20230206034344.724593-1-jaegeuk@kernel.org>
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On 2023/2/6 11:43, Jaegeuk Kim wrote:
> We should return when io->bio is null before doing anything. Otherwise, panic.
> 
> BUG: kernel NULL pointer dereference, address: 0000000000000010
> RIP: 0010:__submit_merged_write_cond+0x164/0x240 [f2fs]
> Call Trace:
>   <TASK>
>   f2fs_submit_merged_write+0x1d/0x30 [f2fs]
>   commit_checkpoint+0x110/0x1e0 [f2fs]
>   f2fs_write_checkpoint+0x9f7/0xf00 [f2fs]
>   ? __pfx_issue_checkpoint_thread+0x10/0x10 [f2fs]
>   __checkpoint_and_complete_reqs+0x84/0x190 [f2fs]
>   ? preempt_count_add+0x82/0xc0
>   ? __pfx_issue_checkpoint_thread+0x10/0x10 [f2fs]
>   issue_checkpoint_thread+0x4c/0xf0 [f2fs]
>   ? __pfx_autoremove_wake_function+0x10/0x10
>   kthread+0xff/0x130
>   ? __pfx_kthread+0x10/0x10
>   ret_from_fork+0x2c/0x50
>   </TASK>
> 
> Cc: stable@vger.kernel.org # v5.18+
> Fixes: 64bf0eef0171 ("f2fs: pass the bio operation to bio_alloc_bioset")
> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

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

Thanks,