From dacb5d8875cc6cd3a553363b4d6f06760fcbe70c Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Fri, 26 Nov 2021 19:34:21 +0100 Subject: tcp: fix page frag corruption on page fault Steffen reported a TCP stream corruption for HTTP requests served by the apache web-server using a cifs mount-point and memory mapping the relevant file. The root cause is quite similar to the one addressed by commit 20eb4f29b602 ("net: fix sk_page_frag() recursion from memory reclaim"). Here the nested access to the task page frag is caused by a page fault on the (mmapped) user-space memory buffer coming from the cifs file. The page fault handler performs an smb transaction on a different socket, inside the same process context. Since sk->sk_allaction for such socket does not prevent the usage for the task_frag, the nested allocation modify "under the hood" the page frag in use by the outer sendmsg call, corrupting the stream. The overall relevant stack trace looks like the following: httpd 78268 [001] 3461630.850950: probe:tcp_sendmsg_locked: ffffffff91461d91 tcp_sendmsg_locked+0x1 ffffffff91462b57 tcp_sendmsg+0x27 ffffffff9139814e sock_sendmsg+0x3e ffffffffc06dfe1d smb_send_kvec+0x28 [...] ffffffffc06cfaf8 cifs_readpages+0x213 ffffffff90e83c4b read_pages+0x6b ffffffff90e83f31 __do_page_cache_readahead+0x1c1 ffffffff90e79e98 filemap_fault+0x788 ffffffff90eb0458 __do_fault+0x38 ffffffff90eb5280 do_fault+0x1a0 ffffffff90eb7c84 __handle_mm_fault+0x4d4 ffffffff90eb8093 handle_mm_fault+0xc3 ffffffff90c74f6d __do_page_fault+0x1ed ffffffff90c75277 do_page_fault+0x37 ffffffff9160111e page_fault+0x1e ffffffff9109e7b5 copyin+0x25 ffffffff9109eb40 _copy_from_iter_full+0xe0 ffffffff91462370 tcp_sendmsg_locked+0x5e0 ffffffff91462370 tcp_sendmsg_locked+0x5e0 ffffffff91462b57 tcp_sendmsg+0x27 ffffffff9139815c sock_sendmsg+0x4c ffffffff913981f7 sock_write_iter+0x97 ffffffff90f2cc56 do_iter_readv_writev+0x156 ffffffff90f2dff0 do_iter_write+0x80 ffffffff90f2e1c3 vfs_writev+0xa3 ffffffff90f2e27c do_writev+0x5c ffffffff90c042bb do_syscall_64+0x5b ffffffff916000ad entry_SYSCALL_64_after_hwframe+0x65 The cifs filesystem rightfully sets sk_allocations to GFP_NOFS, we can avoid the nesting using the sk page frag for allocation lacking the __GFP_FS flag. Do not define an additional mm-helper for that, as this is strictly tied to the sk page frag usage. v1 -> v2: - use a stricted sk_page_frag() check instead of reordering the code (Eric) Reported-by: Steffen Froemer Fixes: 5640f7685831 ("net: use a per task frag allocator") Signed-off-by: Paolo Abeni Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller --- include/net/sock.h | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) (limited to 'include/net') diff --git a/include/net/sock.h b/include/net/sock.h index b32906e1ab55..715cdb4b2b79 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -2430,19 +2430,22 @@ static inline void sk_stream_moderate_sndbuf(struct sock *sk) * @sk: socket * * Use the per task page_frag instead of the per socket one for - * optimization when we know that we're in the normal context and owns + * optimization when we know that we're in process context and own * everything that's associated with %current. * - * gfpflags_allow_blocking() isn't enough here as direct reclaim may nest - * inside other socket operations and end up recursing into sk_page_frag() - * while it's already in use. + * Both direct reclaim and page faults can nest inside other + * socket operations and end up recursing into sk_page_frag() + * while it's already in use: explicitly avoid task page_frag + * usage if the caller is potentially doing any of them. + * This assumes that page fault handlers use the GFP_NOFS flags. * * Return: a per task page_frag if context allows that, * otherwise a per socket one. */ static inline struct page_frag *sk_page_frag(struct sock *sk) { - if (gfpflags_normal_context(sk->sk_allocation)) + if ((sk->sk_allocation & (__GFP_DIRECT_RECLAIM | __GFP_MEMALLOC | __GFP_FS)) == + (__GFP_DIRECT_RECLAIM | __GFP_FS)) return ¤t->task_frag; return &sk->sk_frag; -- cgit v1.2.3-59-g8ed1b From cdef485217d30382f3bf6448c54b4401648fe3f1 Mon Sep 17 00:00:00 2001 From: msizanoen1 Date: Tue, 23 Nov 2021 13:48:32 +0100 Subject: ipv6: fix memory leak in fib6_rule_suppress The kernel leaks memory when a `fib` rule is present in IPv6 nftables firewall rules and a suppress_prefix rule is present in the IPv6 routing rules (used by certain tools such as wg-quick). In such scenarios, every incoming packet will leak an allocation in `ip6_dst_cache` slab cache. After some hours of `bpftrace`-ing and source code reading, I tracked down the issue to ca7a03c41753 ("ipv6: do not free rt if FIB_LOOKUP_NOREF is set on suppress rule"). The problem with that change is that the generic `args->flags` always have `FIB_LOOKUP_NOREF` set[1][2] but the IPv6-specific flag `RT6_LOOKUP_F_DST_NOREF` might not be, leading to `fib6_rule_suppress` not decreasing the refcount when needed. How to reproduce: - Add the following nftables rule to a prerouting chain: meta nfproto ipv6 fib saddr . mark . iif oif missing drop This can be done with: sudo nft create table inet test sudo nft create chain inet test test_chain '{ type filter hook prerouting priority filter + 10; policy accept; }' sudo nft add rule inet test test_chain meta nfproto ipv6 fib saddr . mark . iif oif missing drop - Run: sudo ip -6 rule add table main suppress_prefixlength 0 - Watch `sudo slabtop -o | grep ip6_dst_cache` to see memory usage increase with every incoming ipv6 packet. This patch exposes the protocol-specific flags to the protocol specific `suppress` function, and check the protocol-specific `flags` argument for RT6_LOOKUP_F_DST_NOREF instead of the generic FIB_LOOKUP_NOREF when decreasing the refcount, like this. [1]: https://github.com/torvalds/linux/blob/ca7a03c4175366a92cee0ccc4fec0038c3266e26/net/ipv6/fib6_rules.c#L71 [2]: https://github.com/torvalds/linux/blob/ca7a03c4175366a92cee0ccc4fec0038c3266e26/net/ipv6/fib6_rules.c#L99 Link: https://bugzilla.kernel.org/show_bug.cgi?id=215105 Fixes: ca7a03c41753 ("ipv6: do not free rt if FIB_LOOKUP_NOREF is set on suppress rule") Cc: stable@vger.kernel.org Signed-off-by: Jason A. Donenfeld Signed-off-by: David S. Miller --- include/net/fib_rules.h | 4 +++- net/core/fib_rules.c | 2 +- net/ipv4/fib_rules.c | 1 + net/ipv6/fib6_rules.c | 4 ++-- 4 files changed, 7 insertions(+), 4 deletions(-) (limited to 'include/net') diff --git a/include/net/fib_rules.h b/include/net/fib_rules.h index 4b10676c69d1..bd07484ab9dd 100644 --- a/include/net/fib_rules.h +++ b/include/net/fib_rules.h @@ -69,7 +69,7 @@ struct fib_rules_ops { int (*action)(struct fib_rule *, struct flowi *, int, struct fib_lookup_arg *); - bool (*suppress)(struct fib_rule *, + bool (*suppress)(struct fib_rule *, int, struct fib_lookup_arg *); int (*match)(struct fib_rule *, struct flowi *, int); @@ -218,7 +218,9 @@ INDIRECT_CALLABLE_DECLARE(int fib4_rule_action(struct fib_rule *rule, struct fib_lookup_arg *arg)); INDIRECT_CALLABLE_DECLARE(bool fib6_rule_suppress(struct fib_rule *rule, + int flags, struct fib_lookup_arg *arg)); INDIRECT_CALLABLE_DECLARE(bool fib4_rule_suppress(struct fib_rule *rule, + int flags, struct fib_lookup_arg *arg)); #endif diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c index 79df7cd9dbc1..1bb567a3b329 100644 --- a/net/core/fib_rules.c +++ b/net/core/fib_rules.c @@ -323,7 +323,7 @@ jumped: if (!err && ops->suppress && INDIRECT_CALL_MT(ops->suppress, fib6_rule_suppress, fib4_rule_suppress, - rule, arg)) + rule, flags, arg)) continue; if (err != -EAGAIN) { diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c index ce54a30c2ef1..364ad3446b2f 100644 --- a/net/ipv4/fib_rules.c +++ b/net/ipv4/fib_rules.c @@ -141,6 +141,7 @@ INDIRECT_CALLABLE_SCOPE int fib4_rule_action(struct fib_rule *rule, } INDIRECT_CALLABLE_SCOPE bool fib4_rule_suppress(struct fib_rule *rule, + int flags, struct fib_lookup_arg *arg) { struct fib_result *result = (struct fib_result *) arg->result; diff --git a/net/ipv6/fib6_rules.c b/net/ipv6/fib6_rules.c index 40f3e4f9f33a..dcedfe29d9d9 100644 --- a/net/ipv6/fib6_rules.c +++ b/net/ipv6/fib6_rules.c @@ -267,6 +267,7 @@ INDIRECT_CALLABLE_SCOPE int fib6_rule_action(struct fib_rule *rule, } INDIRECT_CALLABLE_SCOPE bool fib6_rule_suppress(struct fib_rule *rule, + int flags, struct fib_lookup_arg *arg) { struct fib6_result *res = arg->result; @@ -294,8 +295,7 @@ INDIRECT_CALLABLE_SCOPE bool fib6_rule_suppress(struct fib_rule *rule, return false; suppress_route: - if (!(arg->flags & FIB_LOOKUP_NOREF)) - ip6_rt_put(rt); + ip6_rt_put_flags(rt, flags); return true; } -- cgit v1.2.3-59-g8ed1b From 20ae1d6aa159eb91a9bf09ff92ccaa94dbea92c2 Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Mon, 29 Nov 2021 10:39:25 -0500 Subject: wireguard: device: reset peer src endpoint when netns exits MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Each peer's endpoint contains a dst_cache entry that takes a reference to another netdev. When the containing namespace exits, we take down the socket and prevent future sockets from being created (by setting creating_net to NULL), which removes that potential reference on the netns. However, it doesn't release references to the netns that a netdev cached in dst_cache might be taking, so the netns still might fail to exit. Since the socket is gimped anyway, we can simply clear all the dst_caches (by way of clearing the endpoint src), which will release all references. However, the current dst_cache_reset function only releases those references lazily. But it turns out that all of our usages of wg_socket_clear_peer_endpoint_src are called from contexts that are not exactly high-speed or bottle-necked. For example, when there's connection difficulty, or when userspace is reconfiguring the interface. And in particular for this patch, when the netns is exiting. So for those cases, it makes more sense to call dst_release immediately. For that, we add a small helper function to dst_cache. This patch also adds a test to netns.sh from Hangbin Liu to ensure this doesn't regress. Tested-by: Hangbin Liu Reported-by: Xiumei Mu Cc: Toke Høiland-Jørgensen Cc: Paolo Abeni Fixes: 900575aa33a3 ("wireguard: device: avoid circular netns references") Signed-off-by: Jason A. Donenfeld Signed-off-by: Jakub Kicinski --- drivers/net/wireguard/device.c | 3 +++ drivers/net/wireguard/socket.c | 2 +- include/net/dst_cache.h | 11 +++++++++++ net/core/dst_cache.c | 19 +++++++++++++++++++ tools/testing/selftests/wireguard/netns.sh | 24 +++++++++++++++++++++++- 5 files changed, 57 insertions(+), 2 deletions(-) (limited to 'include/net') diff --git a/drivers/net/wireguard/device.c b/drivers/net/wireguard/device.c index 551ddaaaf540..77e64ea6be67 100644 --- a/drivers/net/wireguard/device.c +++ b/drivers/net/wireguard/device.c @@ -398,6 +398,7 @@ static struct rtnl_link_ops link_ops __read_mostly = { static void wg_netns_pre_exit(struct net *net) { struct wg_device *wg; + struct wg_peer *peer; rtnl_lock(); list_for_each_entry(wg, &device_list, device_list) { @@ -407,6 +408,8 @@ static void wg_netns_pre_exit(struct net *net) mutex_lock(&wg->device_update_lock); rcu_assign_pointer(wg->creating_net, NULL); wg_socket_reinit(wg, NULL, NULL); + list_for_each_entry(peer, &wg->peer_list, peer_list) + wg_socket_clear_peer_endpoint_src(peer); mutex_unlock(&wg->device_update_lock); } } diff --git a/drivers/net/wireguard/socket.c b/drivers/net/wireguard/socket.c index 8c496b747108..6f07b949cb81 100644 --- a/drivers/net/wireguard/socket.c +++ b/drivers/net/wireguard/socket.c @@ -308,7 +308,7 @@ void wg_socket_clear_peer_endpoint_src(struct wg_peer *peer) { write_lock_bh(&peer->endpoint_lock); memset(&peer->endpoint.src6, 0, sizeof(peer->endpoint.src6)); - dst_cache_reset(&peer->endpoint_cache); + dst_cache_reset_now(&peer->endpoint_cache); write_unlock_bh(&peer->endpoint_lock); } diff --git a/include/net/dst_cache.h b/include/net/dst_cache.h index 67634675e919..df6622a5fe98 100644 --- a/include/net/dst_cache.h +++ b/include/net/dst_cache.h @@ -79,6 +79,17 @@ static inline void dst_cache_reset(struct dst_cache *dst_cache) dst_cache->reset_ts = jiffies; } +/** + * dst_cache_reset_now - invalidate the cache contents immediately + * @dst_cache: the cache + * + * The caller must be sure there are no concurrent users, as this frees + * all dst_cache users immediately, rather than waiting for the next + * per-cpu usage like dst_cache_reset does. Most callers should use the + * higher speed lazily-freed dst_cache_reset function instead. + */ +void dst_cache_reset_now(struct dst_cache *dst_cache); + /** * dst_cache_init - initialize the cache, allocating the required storage * @dst_cache: the cache diff --git a/net/core/dst_cache.c b/net/core/dst_cache.c index be74ab4551c2..0ccfd5fa5cb9 100644 --- a/net/core/dst_cache.c +++ b/net/core/dst_cache.c @@ -162,3 +162,22 @@ void dst_cache_destroy(struct dst_cache *dst_cache) free_percpu(dst_cache->cache); } EXPORT_SYMBOL_GPL(dst_cache_destroy); + +void dst_cache_reset_now(struct dst_cache *dst_cache) +{ + int i; + + if (!dst_cache->cache) + return; + + dst_cache->reset_ts = jiffies; + for_each_possible_cpu(i) { + struct dst_cache_pcpu *idst = per_cpu_ptr(dst_cache->cache, i); + struct dst_entry *dst = idst->dst; + + idst->cookie = 0; + idst->dst = NULL; + dst_release(dst); + } +} +EXPORT_SYMBOL_GPL(dst_cache_reset_now); diff --git a/tools/testing/selftests/wireguard/netns.sh b/tools/testing/selftests/wireguard/netns.sh index 2e5c1630885e..8a9461aa0878 100755 --- a/tools/testing/selftests/wireguard/netns.sh +++ b/tools/testing/selftests/wireguard/netns.sh @@ -613,6 +613,28 @@ ip0 link set wg0 up kill $ncat_pid ip0 link del wg0 +# Ensure that dst_cache references don't outlive netns lifetime +ip1 link add dev wg0 type wireguard +ip2 link add dev wg0 type wireguard +configure_peers +ip1 link add veth1 type veth peer name veth2 +ip1 link set veth2 netns $netns2 +ip1 addr add fd00:aa::1/64 dev veth1 +ip2 addr add fd00:aa::2/64 dev veth2 +ip1 link set veth1 up +ip2 link set veth2 up +waitiface $netns1 veth1 +waitiface $netns2 veth2 +ip1 -6 route add default dev veth1 via fd00:aa::2 +ip2 -6 route add default dev veth2 via fd00:aa::1 +n1 wg set wg0 peer "$pub2" endpoint [fd00:aa::2]:2 +n2 wg set wg0 peer "$pub1" endpoint [fd00:aa::1]:1 +n1 ping6 -c 1 fd00::2 +pp ip netns delete $netns1 +pp ip netns delete $netns2 +pp ip netns add $netns1 +pp ip netns add $netns2 + # Ensure there aren't circular reference loops ip1 link add wg1 type wireguard ip2 link add wg2 type wireguard @@ -631,7 +653,7 @@ while read -t 0.1 -r line 2>/dev/null || [[ $? -ne 142 ]]; do done < /dev/kmsg alldeleted=1 for object in "${!objects[@]}"; do - if [[ ${objects["$object"]} != *createddestroyed ]]; then + if [[ ${objects["$object"]} != *createddestroyed && ${objects["$object"]} != *createdcreateddestroyeddestroyed ]]; then echo "Error: $object: merely ${objects["$object"]}" >&3 alldeleted=0 fi -- cgit v1.2.3-59-g8ed1b From a37a0ee4d25c152a087c5e913b76f207eaebdb54 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 30 Nov 2021 10:29:39 -0800 Subject: net: avoid uninit-value from tcp_conn_request A recent change triggers a KMSAN warning, because request sockets do not initialize @sk_rx_queue_mapping field. Add sk_rx_queue_update() helper to make our intent clear. BUG: KMSAN: uninit-value in sk_rx_queue_set include/net/sock.h:1922 [inline] BUG: KMSAN: uninit-value in tcp_conn_request+0x3bcc/0x4dc0 net/ipv4/tcp_input.c:6922 sk_rx_queue_set include/net/sock.h:1922 [inline] tcp_conn_request+0x3bcc/0x4dc0 net/ipv4/tcp_input.c:6922 tcp_v4_conn_request+0x218/0x2a0 net/ipv4/tcp_ipv4.c:1528 tcp_rcv_state_process+0x2c5/0x3290 net/ipv4/tcp_input.c:6406 tcp_v4_do_rcv+0xb4e/0x1330 net/ipv4/tcp_ipv4.c:1738 tcp_v4_rcv+0x468d/0x4ed0 net/ipv4/tcp_ipv4.c:2100 ip_protocol_deliver_rcu+0x760/0x10b0 net/ipv4/ip_input.c:204 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ip_local_deliver+0x584/0x8c0 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:460 [inline] ip_sublist_rcv_finish net/ipv4/ip_input.c:551 [inline] ip_list_rcv_finish net/ipv4/ip_input.c:601 [inline] ip_sublist_rcv+0x11fd/0x1520 net/ipv4/ip_input.c:609 ip_list_rcv+0x95f/0x9a0 net/ipv4/ip_input.c:644 __netif_receive_skb_list_ptype net/core/dev.c:5505 [inline] __netif_receive_skb_list_core+0xe34/0x1240 net/core/dev.c:5553 __netif_receive_skb_list+0x7fc/0x960 net/core/dev.c:5605 netif_receive_skb_list_internal+0x868/0xde0 net/core/dev.c:5696 gro_normal_list net/core/dev.c:5850 [inline] napi_complete_done+0x579/0xdd0 net/core/dev.c:6587 virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline] virtnet_poll+0x17b6/0x2350 drivers/net/virtio_net.c:1557 __napi_poll+0x14e/0xbc0 net/core/dev.c:7020 napi_poll net/core/dev.c:7087 [inline] net_rx_action+0x824/0x1880 net/core/dev.c:7174 __do_softirq+0x1fe/0x7eb kernel/softirq.c:558 invoke_softirq+0xa4/0x130 kernel/softirq.c:432 __irq_exit_rcu kernel/softirq.c:636 [inline] irq_exit_rcu+0x76/0x130 kernel/softirq.c:648 common_interrupt+0xb6/0xd0 arch/x86/kernel/irq.c:240 asm_common_interrupt+0x1e/0x40 smap_restore arch/x86/include/asm/smap.h:67 [inline] get_shadow_origin_ptr mm/kmsan/instrumentation.c:31 [inline] __msan_metadata_ptr_for_load_1+0x28/0x30 mm/kmsan/instrumentation.c:63 tomoyo_check_acl+0x1b0/0x630 security/tomoyo/domain.c:173 tomoyo_path_permission security/tomoyo/file.c:586 [inline] tomoyo_check_open_permission+0x61f/0xe10 security/tomoyo/file.c:777 tomoyo_file_open+0x24f/0x2d0 security/tomoyo/tomoyo.c:311 security_file_open+0xb1/0x1f0 security/security.c:1635 do_dentry_open+0x4e4/0x1bf0 fs/open.c:809 vfs_open+0xaf/0xe0 fs/open.c:957 do_open fs/namei.c:3426 [inline] path_openat+0x52f1/0x5dd0 fs/namei.c:3559 do_filp_open+0x306/0x760 fs/namei.c:3586 do_sys_openat2+0x263/0x8f0 fs/open.c:1212 do_sys_open fs/open.c:1228 [inline] __do_sys_open fs/open.c:1236 [inline] __se_sys_open fs/open.c:1232 [inline] __x64_sys_open+0x314/0x380 fs/open.c:1232 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x44/0xae Uninit was created at: __alloc_pages+0xbc7/0x10a0 mm/page_alloc.c:5409 alloc_pages+0x8a5/0xb80 alloc_slab_page mm/slub.c:1810 [inline] allocate_slab+0x287/0x1c20 mm/slub.c:1947 new_slab mm/slub.c:2010 [inline] ___slab_alloc+0xbdf/0x1e90 mm/slub.c:3039 __slab_alloc mm/slub.c:3126 [inline] slab_alloc_node mm/slub.c:3217 [inline] slab_alloc mm/slub.c:3259 [inline] kmem_cache_alloc+0xbb3/0x11c0 mm/slub.c:3264 reqsk_alloc include/net/request_sock.h:91 [inline] inet_reqsk_alloc+0xaf/0x8b0 net/ipv4/tcp_input.c:6712 tcp_conn_request+0x910/0x4dc0 net/ipv4/tcp_input.c:6852 tcp_v4_conn_request+0x218/0x2a0 net/ipv4/tcp_ipv4.c:1528 tcp_rcv_state_process+0x2c5/0x3290 net/ipv4/tcp_input.c:6406 tcp_v4_do_rcv+0xb4e/0x1330 net/ipv4/tcp_ipv4.c:1738 tcp_v4_rcv+0x468d/0x4ed0 net/ipv4/tcp_ipv4.c:2100 ip_protocol_deliver_rcu+0x760/0x10b0 net/ipv4/ip_input.c:204 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ip_local_deliver+0x584/0x8c0 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:460 [inline] ip_sublist_rcv_finish net/ipv4/ip_input.c:551 [inline] ip_list_rcv_finish net/ipv4/ip_input.c:601 [inline] ip_sublist_rcv+0x11fd/0x1520 net/ipv4/ip_input.c:609 ip_list_rcv+0x95f/0x9a0 net/ipv4/ip_input.c:644 __netif_receive_skb_list_ptype net/core/dev.c:5505 [inline] __netif_receive_skb_list_core+0xe34/0x1240 net/core/dev.c:5553 __netif_receive_skb_list+0x7fc/0x960 net/core/dev.c:5605 netif_receive_skb_list_internal+0x868/0xde0 net/core/dev.c:5696 gro_normal_list net/core/dev.c:5850 [inline] napi_complete_done+0x579/0xdd0 net/core/dev.c:6587 virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline] virtnet_poll+0x17b6/0x2350 drivers/net/virtio_net.c:1557 __napi_poll+0x14e/0xbc0 net/core/dev.c:7020 napi_poll net/core/dev.c:7087 [inline] net_rx_action+0x824/0x1880 net/core/dev.c:7174 __do_softirq+0x1fe/0x7eb kernel/softirq.c:558 Fixes: 342159ee394d ("net: avoid dirtying sk->sk_rx_queue_mapping") Signed-off-by: Eric Dumazet Reported-by: syzbot Link: https://lore.kernel.org/r/20211130182939.2584764-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski --- include/net/busy_poll.h | 2 +- include/net/sock.h | 17 +++++++++++++++-- 2 files changed, 16 insertions(+), 3 deletions(-) (limited to 'include/net') diff --git a/include/net/busy_poll.h b/include/net/busy_poll.h index 4202c609bb0b..7994455ec714 100644 --- a/include/net/busy_poll.h +++ b/include/net/busy_poll.h @@ -133,7 +133,7 @@ static inline void sk_mark_napi_id(struct sock *sk, const struct sk_buff *skb) if (unlikely(READ_ONCE(sk->sk_napi_id) != skb->napi_id)) WRITE_ONCE(sk->sk_napi_id, skb->napi_id); #endif - sk_rx_queue_set(sk, skb); + sk_rx_queue_update(sk, skb); } static inline void __sk_mark_napi_id_once(struct sock *sk, unsigned int napi_id) diff --git a/include/net/sock.h b/include/net/sock.h index 715cdb4b2b79..bea21ff70e74 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1913,18 +1913,31 @@ static inline int sk_tx_queue_get(const struct sock *sk) return -1; } -static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb) +static inline void __sk_rx_queue_set(struct sock *sk, + const struct sk_buff *skb, + bool force_set) { #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING if (skb_rx_queue_recorded(skb)) { u16 rx_queue = skb_get_rx_queue(skb); - if (unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue)) + if (force_set || + unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue)) WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue); } #endif } +static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb) +{ + __sk_rx_queue_set(sk, skb, true); +} + +static inline void sk_rx_queue_update(struct sock *sk, const struct sk_buff *skb) +{ + __sk_rx_queue_set(sk, skb, false); +} + static inline void sk_rx_queue_clear(struct sock *sk) { #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING -- cgit v1.2.3-59-g8ed1b From 213f5f8f31f10aa1e83187ae20fb7fa4e626b724 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 1 Dec 2021 18:26:35 -0800 Subject: ipv4: convert fib_num_tclassid_users to atomic_t Before commit faa041a40b9f ("ipv4: Create cleanup helper for fib_nh") changes to net->ipv4.fib_num_tclassid_users were protected by RTNL. After the change, this is no longer the case, as free_fib_info_rcu() runs after rcu grace period, without rtnl being held. Fixes: faa041a40b9f ("ipv4: Create cleanup helper for fib_nh") Signed-off-by: Eric Dumazet Cc: David Ahern Reviewed-by: David Ahern Signed-off-by: David S. Miller --- include/net/ip_fib.h | 2 +- include/net/netns/ipv4.h | 2 +- net/ipv4/fib_frontend.c | 2 +- net/ipv4/fib_rules.c | 4 ++-- net/ipv4/fib_semantics.c | 4 ++-- 5 files changed, 7 insertions(+), 7 deletions(-) (limited to 'include/net') diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h index ab5348e57db1..3417ba2d27ad 100644 --- a/include/net/ip_fib.h +++ b/include/net/ip_fib.h @@ -438,7 +438,7 @@ int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, #ifdef CONFIG_IP_ROUTE_CLASSID static inline int fib_num_tclassid_users(struct net *net) { - return net->ipv4.fib_num_tclassid_users; + return atomic_read(&net->ipv4.fib_num_tclassid_users); } #else static inline int fib_num_tclassid_users(struct net *net) diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h index 2f65701a43c9..6c5b2efc4f17 100644 --- a/include/net/netns/ipv4.h +++ b/include/net/netns/ipv4.h @@ -65,7 +65,7 @@ struct netns_ipv4 { bool fib_has_custom_local_routes; bool fib_offload_disabled; #ifdef CONFIG_IP_ROUTE_CLASSID - int fib_num_tclassid_users; + atomic_t fib_num_tclassid_users; #endif struct hlist_head *fib_table_hash; struct sock *fibnl; diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index 9fe13e4f5d08..4d61ddd8a0ec 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -1582,7 +1582,7 @@ static int __net_init fib_net_init(struct net *net) int error; #ifdef CONFIG_IP_ROUTE_CLASSID - net->ipv4.fib_num_tclassid_users = 0; + atomic_set(&net->ipv4.fib_num_tclassid_users, 0); #endif error = ip_fib_net_init(net); if (error < 0) diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c index 364ad3446b2f..d279cb8ac158 100644 --- a/net/ipv4/fib_rules.c +++ b/net/ipv4/fib_rules.c @@ -264,7 +264,7 @@ static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb, if (tb[FRA_FLOW]) { rule4->tclassid = nla_get_u32(tb[FRA_FLOW]); if (rule4->tclassid) - net->ipv4.fib_num_tclassid_users++; + atomic_inc(&net->ipv4.fib_num_tclassid_users); } #endif @@ -296,7 +296,7 @@ static int fib4_rule_delete(struct fib_rule *rule) #ifdef CONFIG_IP_ROUTE_CLASSID if (((struct fib4_rule *)rule)->tclassid) - net->ipv4.fib_num_tclassid_users--; + atomic_dec(&net->ipv4.fib_num_tclassid_users); #endif net->ipv4.fib_has_custom_rules = true; diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index 3364cb9c67e0..fde7797b5806 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -220,7 +220,7 @@ void fib_nh_release(struct net *net, struct fib_nh *fib_nh) { #ifdef CONFIG_IP_ROUTE_CLASSID if (fib_nh->nh_tclassid) - net->ipv4.fib_num_tclassid_users--; + atomic_dec(&net->ipv4.fib_num_tclassid_users); #endif fib_nh_common_release(&fib_nh->nh_common); } @@ -632,7 +632,7 @@ int fib_nh_init(struct net *net, struct fib_nh *nh, #ifdef CONFIG_IP_ROUTE_CLASSID nh->nh_tclassid = cfg->fc_flow; if (nh->nh_tclassid) - net->ipv4.fib_num_tclassid_users++; + atomic_inc(&net->ipv4.fib_num_tclassid_users); #endif #ifdef CONFIG_IP_ROUTE_MULTIPATH nh->fib_nh_weight = nh_weight; -- cgit v1.2.3-59-g8ed1b