The sufile, a metadata file that holds metadata for segment management,
has statistical information in its first block, but if reading this
block fails, it receives the internal code -ENOENT and returns it
unchanged to the callers.
To prevent this -ENOENT from being propagated to system calls, if
reading the header block fails, return -EIO (or -EINVAL depending on
the context) instead.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx>
---
fs/nilfs2/sufile.c | 23 ++++++++++++++++++-----
1 file changed, 18 insertions(+), 5 deletions(-)
diff --git a/fs/nilfs2/sufile.c b/fs/nilfs2/sufile.c
index 7bfc0860acee..f071eba48163 100644
--- a/fs/nilfs2/sufile.c
+++ b/fs/nilfs2/sufile.c
@@ -79,10 +79,17 @@ nilfs_sufile_block_get_segment_usage(const struct inode *sufile, __u64 segnum,
NILFS_MDT(sufile)->mi_entry_size;
}
-static inline int nilfs_sufile_get_header_block(struct inode *sufile,
- struct buffer_head **bhp)
+static int nilfs_sufile_get_header_block(struct inode *sufile,
+ struct buffer_head **bhp)
{
- return nilfs_mdt_get_block(sufile, 0, 0, NULL, bhp);
+ int err = nilfs_mdt_get_block(sufile, 0, 0, NULL, bhp);
+
+ if (unlikely(err == -ENOENT)) {
+ nilfs_error(sufile->i_sb,
+ "missing header block in segment usage metadata");
+ err = -EIO;
+ }
+ return err;
}
static inline int
@@ -1237,9 +1244,15 @@ int nilfs_sufile_read(struct super_block *sb, size_t susize,
if (err)
goto failed;
- err = nilfs_sufile_get_header_block(sufile, &header_bh);
- if (err)
+ err = nilfs_mdt_get_block(sufile, 0, 0, NULL, &header_bh);
+ if (unlikely(err)) {
+ if (err == -ENOENT) {
+ nilfs_err(sb,
+ "missing header block in segment usage metadata");
+ err = -EINVAL;
+ }
goto failed;
+ }
sui = NILFS_SUI(sufile);
kaddr = kmap_local_page(header_bh->b_page);
--
2.34.1
