From: Andreas Gruenbacher agruenba@redhat.com
[ 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@redhat.com Reviewed-by: Christoph Hellwig hch@lst.de Reviewed-by: Darrick J. Wong darrick.wong@oracle.com Signed-off-by: Darrick J. Wong darrick.wong@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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.