Re: [PATCH] fs: f2fs: remove WARN_ON in f2fs_is_valid_blkaddr

From: Chao Yu
Date: Fri Apr 08 2022 - 23:46:43 EST


On 2022/4/9 9:34, Dongliang Mu wrote:
On Sat, Apr 9, 2022 at 8:27 AM Chao Yu <chao@xxxxxxxxxx> wrote:

On 2022/4/8 13:22, Dongliang Mu wrote:
From: Dongliang Mu <mudongliangabcd@xxxxxxxxx>

In f2fs_is_valid_blkaddr, if type is DATA_GENERIC_ENHANCE or
DATA_GENERIC_ENHANCE_READ, it invokes WARN_ON(1) not matter
blkaddr is in the range or not.

If we run into the path where we invoke WARN_ON(1) in f2fs_is_valid_blkaddr(),
It means f2fs image may be broken, or there is a bug in f2fs.

So, do you suffer any related issue in your environment?

related issue? Can you explain a little?

If you mean if this warning occurs, any other issues or crash

I mean have you seen any warning info printed in the path of
f2fs_is_valid_blkaddr() before applying this patch, and if so, w/ what
reproducer? or you just figure out this patch from perspective of code
review?

Thanks,

behaviors are generated? I tested on the syzbot. After removing the
WARN_ON, there is no abnormal issue or crash behaviors followed with
the corresponding reproducer.



Thanks,


Fix this by removing WARN_ON.

Note that, syzbot patch testing does not incur any further issues

Reported-by: syzbot+763ae12a2ede1d99d4dc@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Dongliang Mu <mudongliangabcd@xxxxxxxxx>
---
fs/f2fs/checkpoint.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index f5366feea82d..521498b2dd8c 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -158,7 +158,6 @@ static bool __is_bitmap_valid(struct f2fs_sb_info *sbi, block_t blkaddr,
f2fs_err(sbi, "Inconsistent error blkaddr:%u, sit bitmap:%d",
blkaddr, exist);
set_sbi_flag(sbi, SBI_NEED_FSCK);
- WARN_ON(1);
}
return exist;
}
@@ -196,7 +195,6 @@ bool f2fs_is_valid_blkaddr(struct f2fs_sb_info *sbi,
f2fs_warn(sbi, "access invalid blkaddr:%u",
blkaddr);
set_sbi_flag(sbi, SBI_NEED_FSCK);
- WARN_ON(1);
return false;
} else {
return __is_bitmap_valid(sbi, blkaddr, type);