In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
netfilter: nf_tables_offload: suppress WARN_ON_ONCE for ENOMEM in abort path<\/p>\n
In nft_flow_rule_offload_abort(), WARN_ON_ONCE(err) is triggered on every
\nerror during rollback, including -ENOMEM. Memory allocation failures are
\nexpected under low-memory conditions and do not indicate a kernel bug.<\/p>\n
Trace for example:
\nnft_flow_offload_chain() \/\/ FLOW_BLOCK_BIND
\n nft_flow_block_chain()
\n nft_chain_offload_cmd()
\n nft_block_offload_cmd()
\n ->ndo_setup_tc()
\n nsim_setup_tc()
\n flow_block_cb_setup_simple()
\n flow_block_cb_alloc() \/\/ fails to -ENOMEM<\/p>\n
The warning was reproduced on the 5.10 stable kernel under memory pressure
\nvia fault injection, but the underlying bug exists in mainline as well,
\nas demonstrated by the ENOMEM trace above. The following splat was
\ntriggered during nf_tables transaction processing:<\/p>\n
WARNING: CPU: 0 PID: 8567 at net\/netfilter\/nf_tables_offload.c:532 nft_flow_rule_offload_abort net\/netfilter\/nf_tables_offload.c:532 [inline]
\nWARNING: CPU: 0 PID: 8567 at net\/netfilter\/nf_tables_offload.c:532 nft_flow_rule_offload_commit+0x971\/0xcd0 net\/netfilter\/nf_tables_offload.c:591
\nModules linked in:
\nCPU: 0 PID: 8567 Comm: syz-executor.0 Not tainted 5.10.260-syzkaller #0
\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04\/01\/2014
\nRIP: 0010:nft_flow_rule_offload_abort net\/netfilter\/nf_tables_offload.c:532 [inline]
\nRIP: 0010:nft_flow_rule_offload_commit+0x971\/0xcd0 net\/netfilter\/nf_tables_offload.c:591
\nCall Trace:
\n nf_tables_commit+0x3bd\/0x4bd0 net\/netfilter\/nf_tables_api.c:8604
\n nfnetlink_rcv_batch+0xb1e\/0x1f20 net\/netfilter\/nfnetlink.c:509
\n nfnetlink_rcv_skb_batch net\/netfilter\/nfnetlink.c:579 [inline]
\n nfnetlink_rcv+0x3b3\/0x420 net\/netfilter\/nfnetlink.c:597
\n netlink_unicast_kernel net\/netlink\/af_netlink.c:1314 [inline]
\n netlink_unicast+0x6cd\/0xa00 net\/netfilter\/af_netlink.c:1340
\n netlink_sendmsg+0x906\/0xe10 net\/netfilter\/af_netlink.c:1919
\n sock_sendmsg_nosec net\/socket.c:651 [inline]
\n __sock_sendmsg+0x155\/0x190 net\/socket.c:663
\n ____sys_sendmsg+0x705\/0x870 net\/socket.c:2379
\n ___sys_sendmsg+0x100\/0x170 net\/socket.c:2433
\n __sys_sendmsg+0xe9\/0x1c0 net\/socket.c:2462
\n do_syscall_64+0x33\/0x40 arch\/x86\/entry\/common.c:46
\n entry_SYSCALL_64_after_hwframe+0x67\/0xd1<\/p>\n
Change the condition to WARN_ON_ONCE(err && err != -ENOMEM) so that
\nwarnings are only emitted for unexpected errors. This aligns with the
\ncommon kernel practice of not warning on -ENOMEM.<\/p>\n
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
netfilter: nf_tables_offload: suppress WARN_ON_ONCE for ENOMEM in abort path<\/p>\n
In nft_flow_rule_offload_abort(), WARN_ON_ONCE(err) i<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-3396","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/3396","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3396"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3396"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3396"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}