[PATCH 3.10 073/139] ext4: in ext4_seek_{hole,data}, return -ENXIO for negative offsets

[Willy Tarreau]

From: "Darrick J. Wong" <darrick.wong@xxxxxxxxxx>

commit 1bd8d6cd3e413d64e543ec3e69ff43e75a1cf1ea upstream.

In the ext4 implementations of SEEK_HOLE and SEEK_DATA, make sure we
return -ENXIO for negative offsets instead of banging around inside
the extent code and returning -EFSCORRUPTED.

Reported-by: Mateusz S <muttdini@xxxxxxxxx>
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx 
Signed-off-by: Willy Tarreau <w@xxxxxx>
---
 fs/ext4/file.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index dfba7b3..ed2bada 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -421,7 +421,7 @@ static loff_t ext4_seek_data(struct file *file, loff_t offset, loff_t maxsize)
 	mutex_lock(&inode->i_mutex);
 
 	isize = i_size_read(inode);
-	if (offset >= isize) {
+	if (offset < 0 || offset >= isize) {
 		mutex_unlock(&inode->i_mutex);
 		return -ENXIO;
 	}
@@ -504,7 +504,7 @@ static loff_t ext4_seek_hole(struct file *file, loff_t offset, loff_t maxsize)
 	mutex_lock(&inode->i_mutex);
 
 	isize = i_size_read(inode);
-	if (offset >= isize) {
+	if (offset < 0 || offset >= isize) {
 		mutex_unlock(&inode->i_mutex);
 		return -ENXIO;
 	}
-- 
2.8.0.rc2.1.gbe9624a