4.14-stable review patch. If anyone has any objections, please let me know.
------------------ [ Upstream commit ce96a407adef126870b3f4a1b73529dd8aa80f49 ] hfs_bmap_free() frees the node via hfs_bnode_put(node). However, it then reads node->this when dumping error message on an error path, which may result in a use-after-free bug. This patch frees the node only when it is never again used. Link: http://lkml.kernel.org/r/1542963889-128825-1-git-send-email-bianpan2...@163.com Fixes: a1185ffa2fc ("HFS rewrite") Signed-off-by: Pan Bian <bianpan2...@163.com> Reviewed-by: Andrew Morton <a...@linux-foundation.org> Cc: Joe Perches <j...@perches.com> Cc: Ernesto A. Fernandez <ernesto.mnd.fernan...@gmail.com> Cc: Viacheslav Dubeyko <sl...@dubeyko.com> Signed-off-by: Andrew Morton <a...@linux-foundation.org> Signed-off-by: Linus Torvalds <torva...@linux-foundation.org> Signed-off-by: Sasha Levin <sas...@kernel.org> --- fs/hfs/btree.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/hfs/btree.c b/fs/hfs/btree.c index 374b5688e29e..9bdff5e40626 100644 --- a/fs/hfs/btree.c +++ b/fs/hfs/btree.c @@ -329,13 +329,14 @@ void hfs_bmap_free(struct hfs_bnode *node) nidx -= len * 8; i = node->next; - hfs_bnode_put(node); if (!i) { /* panic */; pr_crit("unable to free bnode %u. bmap not found!\n", node->this); + hfs_bnode_put(node); return; } + hfs_bnode_put(node); node = hfs_bnode_find(tree, i); if (IS_ERR(node)) return; -- 2.19.1
