linux-ext4 - [PATCH 09/10] e2fsck: require that fast symlinks don't have EXT4_EXTENTS

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Date:   Fri,  2 Mar 2018 16:59:22 -0800
From:   Eric Biggers <ebiggers3@...il.com>
To:     linux-ext4@...r.kernel.org
Cc:     Eric Biggers <ebiggers@...gle.com>
Subject: [PATCH 09/10] e2fsck: require that fast symlinks don't have EXT4_EXTENTS_FL

From: Eric Biggers <ebiggers@...gle.com>

It doesn't make sense for EXT4_EXTENTS_FL to be set on a fast symlink.
The kernel doesn't set it, and it ignores it if set.  Meanwhile, e2fsck
is stricter: it will try to validate the extent tree, which will almost
certainly fail (assuming the symlink is, in fact, a fast symlink).

Make this behavior more explicit by rejecting EXT4_EXTENTS_FL for fast
symlinks, rather than going ahead and trying to validate an extent tree.

Signed-off-by: Eric Biggers <ebiggers@...gle.com>
---
 e2fsck/pass1.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
index 46d70d14..fccd8816 100644
--- a/e2fsck/pass1.c
+++ b/e2fsck/pass1.c
@@ -203,9 +203,9 @@ int e2fsck_pass1_check_symlink(ext2_filsys fs, ext2_ino_t ino,
 		return 1;
 	}

-	if (ext2fs_is_fast_symlink(inode) &&
-	    !(inode->i_flags & EXT4_EXTENTS_FL)) {
-
+	if (ext2fs_is_fast_symlink(inode)) {
+		if (inode->i_flags & EXT4_EXTENTS_FL)
+			return 0;
 		buf = (char *)inode->i_block;
 		buflen = sizeof(inode->i_block);
 	} else {
-- 
2.16.2.395.g2e18187dfd-goog