From: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
[ Upstream commit 856473cd5d17dbbf3055710857c67a4af6d9fcc0 ]
Make sure iomap_end is always called when iomap_begin succeeds.
Without this fix, iomap_end won't be called when a filesystem's
iomap_begin operation returns an invalid mapping, bypassing any
unlocking done in iomap_end. With this fix, the unlocking will still
happen.
This bug was found by Bob Peterson during code review. It's unlikely
that such iomap_begin bugs will survive to affect users, so backporting
this fix seems unnecessary.
Fixes: ae259a9c8593 ("fs: introduce iomap infrastructure")
Signed-off-by: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/iomap/apply.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/fs/iomap/apply.c b/fs/iomap/apply.c
index 54c02aecf3cd8..c2281a6a7f320 100644
--- a/fs/iomap/apply.c
+++ b/fs/iomap/apply.c
@@ -41,10 +41,14 @@ iomap_apply(struct inode *inode, loff_t pos, loff_t length, unsigned flags,
ret = ops->iomap_begin(inode, pos, length, flags, &iomap);
if (ret)
return ret;
- if (WARN_ON(iomap.offset > pos))
- return -EIO;
- if (WARN_ON(iomap.length == 0))
- return -EIO;
+ if (WARN_ON(iomap.offset > pos)) {
+ written = -EIO;
+ goto out;
+ }
+ if (WARN_ON(iomap.length == 0)) {
+ written = -EIO;
+ goto out;
+ }
/*
* Cut down the length to the one actually provided by the filesystem,
@@ -60,6 +64,7 @@ iomap_apply(struct inode *inode, loff_t pos, loff_t length, unsigned flags,
*/
written = actor(inode, pos, length, data, &iomap);
+out:
/*
* Now the data has been copied, commit the range we've copied. This
* should not fail unless the filesystem has had a fatal error.
--
2.25.1
