nf_tables: fix NULL pointer dereference in nft_expr_inner_parse()
authorXingyuan Mo <hdthky0@gmail.com>
Mon, 9 Oct 2023 10:36:15 +0000 (18:36 +0800)
committerFlorian Westphal <fw@strlen.de>
Thu, 12 Oct 2023 08:28:45 +0000 (10:28 +0200)
commit505ce0630ad5d31185695f8a29dde8d29f28faa7
treeee9f50b19eeb959cc0f66f72e4820f510cad0640
parent52177bbf19e6e9398375a148d2e13ed492b40b80
nf_tables: fix NULL pointer dereference in nft_expr_inner_parse()

We should check whether the NFTA_EXPR_NAME netlink attribute is present
before accessing it, otherwise a null pointer deference error will occur.

Call Trace:
 <TASK>
 dump_stack_lvl+0x4f/0x90
 print_report+0x3f0/0x620
 kasan_report+0xcd/0x110
 __asan_load2+0x7d/0xa0
 nla_strcmp+0x2f/0x90
 __nft_expr_type_get+0x41/0xb0
 nft_expr_inner_parse+0xe3/0x200
 nft_inner_init+0x1be/0x2e0
 nf_tables_newrule+0x813/0x1230
 nfnetlink_rcv_batch+0xec3/0x1170
 nfnetlink_rcv+0x1e4/0x220
 netlink_unicast+0x34e/0x4b0
 netlink_sendmsg+0x45c/0x7e0
 __sys_sendto+0x355/0x370
 __x64_sys_sendto+0x84/0xa0
 do_syscall_64+0x3f/0x90
 entry_SYSCALL_64_after_hwframe+0x6e/0xd8

Fixes: 3a07327d10a0 ("netfilter: nft_inner: support for inner tunnel header matching")
Signed-off-by: Xingyuan Mo <hdthky0@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
net/netfilter/nf_tables_api.c