From 909021aed81180c68337ea1963b119af50efb284 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Sun, 5 May 2019 18:47:33 +0200 Subject: [PATCH] netfilter: ebtables: CONFIG_COMPAT: reject trailing data after last rule [ Upstream commit 680f6af5337c98d116e4f127cea7845339dba8da ] If userspace provides a rule blob with trailing data after last target, we trigger a splat, then convert ruleset to 64bit format (with trailing data), then pass that to do_replace_finish() which then returns -EINVAL. Erroring out right away avoids the splat plus unneeded translation and error unwind. Fixes: 81e675c227ec ("netfilter: ebtables: add CONFIG_COMPAT support") Reported-by: Tetsuo Handa Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- net/bridge/netfilter/ebtables.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c index 785e19af..f59230e 100644 --- a/net/bridge/netfilter/ebtables.c +++ b/net/bridge/netfilter/ebtables.c @@ -2165,7 +2165,9 @@ static int compat_copy_entries(unsigned char *data, unsigned int size_user, if (ret < 0) return ret; - WARN_ON(size_remaining); + if (size_remaining) + return -EINVAL; + return state->buf_kern_offset; } -- 2.7.4