From f43f02429295486059605997bc43803527d69791 Mon Sep 17 00:00:00 2001 From: Wentao Liang Date: Tue, 29 Apr 2025 02:37:07 +0900 Subject: [PATCH] nilfs2: add pointer check for nilfs_direct_propagate() Patch series "nilfs2: improve sanity checks in dirty state propagation". This fixes one missed check for block mapping anomalies and one improper return of an error code during a preparation step for log writing, thereby improving checking for filesystem corruption on writeback. This patch (of 2): In nilfs_direct_propagate(), the printer get from nilfs_direct_get_ptr() need to be checked to ensure it is not an invalid pointer. If the pointer value obtained by nilfs_direct_get_ptr() is NILFS_BMAP_INVALID_PTR, means that the metadata (in this case, i_bmap in the nilfs_inode_info struct) that should point to the data block at the buffer head of the argument is corrupted and the data block is orphaned, meaning that the file system has lost consistency. Add a value check and return -EINVAL when it is an invalid pointer. Link: https://lkml.kernel.org/r/20250428173808.6452-1-konishi.ryusuke@gmail.com Link: https://lkml.kernel.org/r/20250428173808.6452-2-konishi.ryusuke@gmail.com Fixes: 36a580eb489f ("nilfs2: direct block mapping") Signed-off-by: Wentao Liang Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton --- fs/nilfs2/direct.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/nilfs2/direct.c b/fs/nilfs2/direct.c index 893ab36824cc2..2d8dc6b35b547 100644 --- a/fs/nilfs2/direct.c +++ b/fs/nilfs2/direct.c @@ -273,6 +273,9 @@ static int nilfs_direct_propagate(struct nilfs_bmap *bmap, dat = nilfs_bmap_get_dat(bmap); key = nilfs_bmap_data_get_key(bmap, bh); ptr = nilfs_direct_get_ptr(bmap, key); + if (ptr == NILFS_BMAP_INVALID_PTR) + return -EINVAL; + if (!buffer_nilfs_volatile(bh)) { oldreq.pr_entry_nr = ptr; newreq.pr_entry_nr = ptr; -- 2.47.2