[RESEND PATCH v9] ext4: Log error when lookup of encoded dentry fails

[Eugen Hristev]

From: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx>

If the volume is in strict mode, ext4_ci_compare can report a broken
encoding name.  This will not trigger on a bad lookup, which is caught
earlier, only if the actual disk name is bad.

Reviewed-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Signed-off-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx>
Signed-off-by: Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx>
---
Hello,

I am trying to respin the series here :
https://www.spinics.net/lists/linux-ext4/msg85081.html

To make it easier to apply I split it into smaller chunks which address
one single thing.

This patch simply adds an error message in the UNICODE path.

 fs/ext4/namei.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 6e7af8dc4dde..7d357c417475 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -1477,6 +1477,9 @@ static bool ext4_match(struct inode *parent,
 			 * only case where it happens is on a disk
 			 * corruption or ENOMEM.
 			 */
+			if (ret == -EINVAL)
+				EXT4_ERROR_INODE(parent,
+					"Directory contains filename that is invalid UTF-8");
 			return false;
 		}
 		return ret;
-- 
2.34.1