Adding stable.
On Oct 21, 2020, at 1:08 PM, Saeed Mirzamohammadi saeed.mirzamohammadi@oracle.com wrote:
Attached the syzkaller C repro.
Tested-by: Saeed Mirzamohammadi saeed.mirzamohammadi@oracle.com <repro.c>
On Oct 20, 2020, at 9:45 AM, Saeed Mirzamohammadi saeed.mirzamohammadi@oracle.com wrote:
Thanks! Yes, that looks good to me.
Saeed
On Oct 20, 2020, at 4:50 AM, Pablo Neira Ayuso pablo@netfilter.org wrote:
On Mon, Oct 19, 2020 at 10:25:32AM -0700, saeed.mirzamohammadi@oracle.com wrote:
From: Saeed Mirzamohammadi saeed.mirzamohammadi@oracle.com
This patch fixes the issue due to:
BUG: KASAN: slab-out-of-bounds in nft_flow_rule_create+0x622/0x6a2 net/netfilter/nf_tables_offload.c:40 Read of size 8 at addr ffff888103910b58 by task syz-executor227/16244
The error happens when expr->ops is accessed early on before performing the boundary check and after nft_expr_next() moves the expr to go out-of-bounds.
This patch checks the boundary condition before expr->ops that fixes the slab-out-of-bounds Read issue.
Thanks. I made a slight variant of your patch.
I'm attaching it, it is also fixing the problem but it introduced nft_expr_more() and use it everywhere.
Let me know if this looks fine to you. <0001-netfilter-fix-KASAN-slab-out-of-bounds-Read-in-nft_f.patch>