Previously, ext2_fiemap would unconditionally apply "len = min_t(u64, len, i_size_read(inode));", When inode->i_size was 0 (for an empty file), this would reduce the requested len to 0. Passing len = 0 to iomap_fiemap could then result in an -EINVAL error, even for valid queries on empty files. The new validation logic directly references ext4_fiemap_check_ranges. Link: https://github.com/linux-test-project/ltp/issues/1246 Signed-off-by: Wei Gao <wegao@xxxxxxxx> --- fs/ext2/inode.c | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-) diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c index 30f8201c155f..e5cc61088f21 100644 --- a/fs/ext2/inode.c +++ b/fs/ext2/inode.c @@ -895,10 +895,30 @@ int ext2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, u64 start, u64 len) { int ret; + u64 maxbytes; inode_lock(inode); - len = min_t(u64, len, i_size_read(inode)); + maxbytes = inode->i_sb->s_maxbytes; + + if (len == 0) { + ret = -EINVAL; + goto unlock_inode; + } + + if (start > maxbytes) { + ret = -EFBIG; + goto unlock_inode; + } + + /* + * Shrink request scope to what the fs can actually handle. + */ + if (len > maxbytes || (maxbytes - len) < start) + len = maxbytes - start; + ret = iomap_fiemap(inode, fieinfo, start, len, &ext2_iomap_ops); + +unlock_inode: inode_unlock(inode); return ret; -- 2.49.0
