From f2538f999345405f7d2e1194c0c8efa4e11f7b3a Mon Sep 17 00:00:00 2001 From: Jia-Ju Bai Date: Wed, 24 Jul 2019 10:46:58 +0800 Subject: [PATCH] jffs2: Fix possible null-pointer dereferences in jffs2_add_frag_to_fragtree() In jffs2_add_frag_to_fragtree(), there is an if statement on line 223 to check whether "this" is NULL: if (this) When "this" is NULL, it is used at several places, such as on line 249: if (this->node) and on line 260: if (newfrag->ofs > this->ofs) Thus possible null-pointer dereferences may occur. To fix these bugs, -EINVAL is returned when "this" is NULL. These bugs are found by a static analysis tool STCheck written by us. Signed-off-by: Jia-Ju Bai Signed-off-by: Richard Weinberger --- fs/jffs2/nodelist.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/jffs2/nodelist.c b/fs/jffs2/nodelist.c index b86c78d178c6..021a4a2190ee 100644 --- a/fs/jffs2/nodelist.c +++ b/fs/jffs2/nodelist.c @@ -226,7 +226,7 @@ static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *r lastend = this->ofs + this->size; } else { dbg_fragtree2("lookup gave no frag\n"); - lastend = 0; + return -EINVAL; } /* See if we ran off the end of the fragtree */