From: Jianyun Gao <[email protected]> When dax_range_compare_iter() returns a negative error code (e.g. -EIO), dax_dedupe_file_range_compare() incorrectly returns 'ret' which holds the positive return value from iomap_iter() indicating more iterations remain. This positive value leaks to the caller, where vfs_dedupe_file_range() interprets it as success (bytes_deduped = len), causing userspace to incorrectly believe deduplication completed.
Return 'status' instead to propagate the actual error code. Signed-off-by: Jianyun Gao <[email protected]> --- fs/dax.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/dax.c b/fs/dax.c index 6ba50142eeb2..1f6a4fbb97bd 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -2261,7 +2261,7 @@ int dax_dedupe_file_range_compare(struct inode *src, loff_t srcoff, status = dax_range_compare_iter(&src_iter, &dst_iter, min(src_iter.len, dst_iter.len), same); if (status < 0) - return ret; + return status; src_iter.status = dst_iter.status = status; } return ret; -- 2.34.1

