summaryrefslogtreecommitdiffstats
path: root/fs/btrfs/extent_io.c
diff options
context:
space:
mode:
authorElena Reshetova2017-03-03 09:55:12 +0100
committerDavid Sterba2017-04-18 14:07:23 +0200
commit490b54d6fb75f6ffd0471ec58bb38a992e2b40cd (patch)
treea7f431ea6a0f4369ba43be8736090efd54d6998b /fs/btrfs/extent_io.c
parentbtrfs: convert btrfs_transaction.use_count from atomic_t to refcount_t (diff)
downloadkernel-qcow2-linux-490b54d6fb75f6ffd0471ec58bb38a992e2b40cd.tar.gz
kernel-qcow2-linux-490b54d6fb75f6ffd0471ec58bb38a992e2b40cd.tar.xz
kernel-qcow2-linux-490b54d6fb75f6ffd0471ec58bb38a992e2b40cd.zip
btrfs: convert extent_map.refs from atomic_t to refcount_t
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/extent_io.c')
-rw-r--r--fs/btrfs/extent_io.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 27fdb250b446..3649932e48d5 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2859,7 +2859,7 @@ __get_extent_map(struct inode *inode, struct page *page, size_t pg_offset,
em = *em_cached;
if (extent_map_in_tree(em) && start >= em->start &&
start < extent_map_end(em)) {
- atomic_inc(&em->refs);
+ refcount_inc(&em->refs);
return em;
}
@@ -2870,7 +2870,7 @@ __get_extent_map(struct inode *inode, struct page *page, size_t pg_offset,
em = get_extent(BTRFS_I(inode), page, pg_offset, start, len, 0);
if (em_cached && !IS_ERR_OR_NULL(em)) {
BUG_ON(*em_cached);
- atomic_inc(&em->refs);
+ refcount_inc(&em->refs);
*em_cached = em;
}
return em;