This is a note to let you know that I've just added the patch titled f2fs: fix to detect inconsistent nat entry during truncation to the 6.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: f2fs-fix-to-detect-inconsistent-nat-entry-during-tru.patch and it can be found in the queue-6.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit deeb3102f02310f6d207ee0fd505976bc9479386 Author: Chao Yu <chao@xxxxxxxxxx> Date: Fri Mar 22 22:59:55 2024 +0800 f2fs: fix to detect inconsistent nat entry during truncation [ Upstream commit 92c556ed6318e13c16746495a8d4513129eb9b0f ] 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 <r.smirnov@xxxxxx> Closes: https://lore.kernel.org/linux-f2fs-devel/085b27fd2b364a3c8c3a9ca77363e246@xxxxxx Signed-off-by: Chao Yu <chao@xxxxxxxxxx> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index 7df5ad84cb5ea..15c9a9f5750bc 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]) {