2024-03-22 15:00:21

by Chao Yu

Subject: [PATCH] f2fs: fix to detect inconsistent nat entry during truncation

As Roman Smirnov reported as below:

"
There is a possible bug in f2fs_truncate_inode_blocks():

if (err < 0 && err != -ENOENT)
goto fail;
...
offset[1] = 0;
offset[0]++;
nofs += err;

If err = -ENOENT then nofs will sum with an error code,
which is strange behaviour. Also if nofs < ENOENT this will
cause an overflow. err will be equal to -ENOENT with the
following call stack:

truncate_nodes()
f2fs_get_node_page()
__get_node_page()
read_node_page()
"

If nat is corrupted, truncate_nodes() may return -ENOENT, and
f2fs_truncate_inode_blocks() doesn't handle such error correctly,
fix it.

Reported-by: Roman Smirnov <[email protected]>
Closes: https://lore.kernel.org/linux-f2fs-devel/[email protected]
Signed-off-by: Chao Yu <[email protected]>
---
fs/f2fs/node.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index b3de6d6cdb02..bb57bbaff7b4 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1187,7 +1187,17 @@ int f2fs_truncate_inode_blocks(struct inode *inode, pgoff_t from)
default:
BUG();
}
- if (err < 0 && err != -ENOENT)
+ if (err == -ENOENT) {
+ set_sbi_flag(F2FS_P_SB(page), SBI_NEED_FSCK);
+ f2fs_handle_error(sbi, ERROR_INVALID_BLKADDR);
+ f2fs_err_ratelimited(sbi,
+ "truncate node fail, ino:%lu, nid:%u, "
+ "offset[0]:%d, offset[1]:%d, nofs:%d",
+ inode->i_ino, dn.nid, offset[0],
+ offset[1], nofs);
+ err = 0;
+ }
+ if (err < 0)
goto fail;
if (offset[1] == 0 &&
ri->i_nid[offset[0] - NODE_DIR1_BLOCK]) {
--
2.40.1

2024-04-14 15:34:27

by patchwork-bot+f2fs

Subject: Re: [f2fs-dev] [PATCH] f2fs: fix to detect inconsistent nat entry during truncation

Hello:

This patch was applied to jaegeuk/f2fs.git (dev)
by Jaegeuk Kim <[email protected]>:

On Fri, 22 Mar 2024 22:59:55 +0800 you wrote:
> As Roman Smirnov reported as below:
>
> "
> There is a possible bug in f2fs_truncate_inode_blocks():
>
> if (err < 0 && err != -ENOENT)
> goto fail;
> ...
> offset[1] = 0;
> offset[0]++;
> nofs += err;
>
> [...]

Here is the summary with links:
- [f2fs-dev] f2fs: fix to detect inconsistent nat entry during truncation
https://git.kernel.org/jaegeuk/f2fs/c/92c556ed6318

You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html