From: Tyler Hicks Date: Tue, 4 Sep 2018 15:24:05 +0000 (+0000) Subject: irda: Only insert new objects into the global database via setsockopt X-Git-Tag: v4.9.127~15 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=18d94895f505d6eef2da8868e87a403cde1d9ef0;p=platform%2Fkernel%2Flinux-amlogic.git irda: Only insert new objects into the global database via setsockopt The irda_setsockopt() function conditionally allocates memory for a new self->ias_object or, in some cases, reuses the existing self->ias_object. Existing objects were incorrectly reinserted into the LM_IAS database which corrupted the doubly linked list used for the hashbin implementation of the LM_IAS database. When combined with a memory leak in irda_bind(), this issue could be leveraged to create a use-after-free vulnerability in the hashbin list. This patch fixes the issue by only inserting newly allocated objects into the database. CVE-2018-6555 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Tyler Hicks Reviewed-by: Seth Arnold Reviewed-by: Stefan Bader Signed-off-by: Greg Kroah-Hartman --- diff --git a/net/irda/af_irda.c b/net/irda/af_irda.c index b85fa22..0a78f17 100644 --- a/net/irda/af_irda.c +++ b/net/irda/af_irda.c @@ -2023,7 +2023,11 @@ static int irda_setsockopt(struct socket *sock, int level, int optname, err = -EINVAL; goto out; } - irias_insert_object(ias_obj); + + /* Only insert newly allocated objects */ + if (free_ias) + irias_insert_object(ias_obj); + kfree(ias_opt); break; case IRLMP_IAS_DEL: