From: Andreas Gruenbacher <agruenba@redhat.com> mainline inclusion from mainline-5.9-rc1 commit 856473cd5d17dbbf3055710857c67a4af6d9fcc0 category: bugfix bugzilla: 40769 CVE: NA --------------------------- 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> [fs/iomap/apply.c not exist, instead fs/iomap.c] Signed-off-by: yangerkun <yangerkun@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- fs/iomap.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/fs/iomap.c b/fs/iomap.c index bb2f966798d3e..fd3439997d292 100644 --- a/fs/iomap.c +++ b/fs/iomap.c @@ -67,10 +67,14 @@ 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, @@ -86,6 +90,7 @@ 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