This is a note to let you know that I've just added the patch titled netfilter: x_tables: don't reject valid target size on some architectures to the 4.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: netfilter-x_tables-don-t-reject-valid-target-size-on-some-architectures.patch and it can be found in the queue-4.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 7b7eba0f3515fca3296b8881d583f7c1042f5226 Mon Sep 17 00:00:00 2001 From: Florian Westphal <fw@xxxxxxxxx> Date: Wed, 1 Jun 2016 02:04:44 +0200 Subject: netfilter: x_tables: don't reject valid target size on some architectures From: Florian Westphal <fw@xxxxxxxxx> commit 7b7eba0f3515fca3296b8881d583f7c1042f5226 upstream. Quoting John Stultz: In updating a 32bit arm device from 4.6 to Linus' current HEAD, I noticed I was having some trouble with networking, and realized that /proc/net/ip_tables_names was suddenly empty. Digging through the registration process, it seems we're catching on the: if (strcmp(t->u.user.name, XT_STANDARD_TARGET) == 0 && target_offset + sizeof(struct xt_standard_target) != next_offset) return -EINVAL; Where next_offset seems to be 4 bytes larger then the offset + standard_target struct size. next_offset needs to be aligned via XT_ALIGN (so we can access all members of ip(6)t_entry struct). This problem didn't show up on i686 as it only needs 4-byte alignment for u64, but iptables userspace on other 32bit arches does insert extra padding. Reported-by: John Stultz <john.stultz@xxxxxxxxxx> Tested-by: John Stultz <john.stultz@xxxxxxxxxx> Fixes: 7ed2abddd20cf ("netfilter: x_tables: check standard target size too") Signed-off-by: Florian Westphal <fw@xxxxxxxxx> Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/netfilter/x_tables.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -609,7 +609,7 @@ int xt_compat_check_entry_offsets(const return -EINVAL; if (strcmp(t->u.user.name, XT_STANDARD_TARGET) == 0 && - target_offset + sizeof(struct compat_xt_standard_target) != next_offset) + COMPAT_XT_ALIGN(target_offset + sizeof(struct compat_xt_standard_target)) != next_offset) return -EINVAL; /* compat_xt_entry match has less strict aligment requirements, @@ -691,7 +691,7 @@ int xt_check_entry_offsets(const void *b return -EINVAL; if (strcmp(t->u.user.name, XT_STANDARD_TARGET) == 0 && - target_offset + sizeof(struct xt_standard_target) != next_offset) + XT_ALIGN(target_offset + sizeof(struct xt_standard_target)) != next_offset) return -EINVAL; return xt_check_entry_match(elems, base + target_offset, Patches currently in stable-queue which might be from fw@xxxxxxxxx are queue-4.6/netfilter-x_tables-add-and-use-xt_check_entry_offsets.patch queue-4.6/netfilter-x_tables-assert-minimum-target-size.patch queue-4.6/netfilter-x_tables-add-compat-version-of-xt_check_entry_offsets.patch queue-4.6/netfilter-x_tables-check-for-bogus-target-offset.patch queue-4.6/netfilter-x_tables-validate-targets-of-jumps.patch queue-4.6/netfilter-x_tables-don-t-move-to-non-existent-next-rule.patch queue-4.6/netfilter-x_tables-kill-check_entry-helper.patch queue-4.6/netfilter-x_tables-check-standard-target-size-too.patch queue-4.6/netfilter-x_tables-validate-all-offsets-and-sizes-in-a-rule.patch queue-4.6/netfilter-x_tables-don-t-reject-valid-target-size-on-some-architectures.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html