From 0532a79efd68a4d9686b0385e4993af4b130ff82 Mon Sep 17 00:00:00 2001 From: Jiayuan Chen Date: Wed, 22 Jan 2025 18:09:13 +0800 Subject: strparser: Add read_sock callback Added a new read_sock handler, allowing users to customize read operations instead of relying on the native socket's read_sock. Signed-off-by: Jiayuan Chen Signed-off-by: Martin KaFai Lau Reviewed-by: Jakub Sitnicki Acked-by: John Fastabend Link: https://patch.msgid.link/20250122100917.49845-2-mrpre@163.com --- include/net/strparser.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/net') diff --git a/include/net/strparser.h b/include/net/strparser.h index 41e2ce9e9e10..0a83010b3a64 100644 --- a/include/net/strparser.h +++ b/include/net/strparser.h @@ -43,6 +43,8 @@ struct strparser; struct strp_callbacks { int (*parse_msg)(struct strparser *strp, struct sk_buff *skb); void (*rcv_msg)(struct strparser *strp, struct sk_buff *skb); + int (*read_sock)(struct strparser *strp, read_descriptor_t *desc, + sk_read_actor_t recv_actor); int (*read_sock_done)(struct strparser *strp, int err); void (*abort_parser)(struct strparser *strp, int err); void (*lock)(struct strparser *strp); -- cgit v1.2.3 From 36b62df5683c315ba58c950f1a9c771c796c30ec Mon Sep 17 00:00:00 2001 From: Jiayuan Chen Date: Wed, 22 Jan 2025 18:09:14 +0800 Subject: bpf: Fix wrong copied_seq calculation MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 'sk->copied_seq' was updated in the tcp_eat_skb() function when the action of a BPF program was SK_REDIRECT. For other actions, like SK_PASS, the update logic for 'sk->copied_seq' was moved to tcp_bpf_recvmsg_parser() to ensure the accuracy of the 'fionread' feature. It works for a single stream_verdict scenario, as it also modified sk_data_ready->sk_psock_verdict_data_ready->tcp_read_skb to remove updating 'sk->copied_seq'. However, for programs where both stream_parser and stream_verdict are active (strparser purpose), tcp_read_sock() was used instead of tcp_read_skb() (sk_data_ready->strp_data_ready->tcp_read_sock). tcp_read_sock() now still updates 'sk->copied_seq', leading to duplicate updates. In summary, for strparser + SK_PASS, copied_seq is redundantly calculated in both tcp_read_sock() and tcp_bpf_recvmsg_parser(). The issue causes incorrect copied_seq calculations, which prevent correct data reads from the recv() interface in user-land. We do not want to add new proto_ops to implement a new version of tcp_read_sock, as this would introduce code complexity [1]. We could have added noack and copied_seq to desc, and then called ops->read_sock. However, unfortunately, other modules didn’t fully initialize desc to zero. So, for now, we are directly calling tcp_read_sock_noack() in tcp_bpf.c. [1]: https://lore.kernel.org/bpf/20241218053408.437295-1-mrpre@163.com Fixes: e5c6de5fa025 ("bpf, sockmap: Incorrectly handling copied_seq") Suggested-by: Jakub Sitnicki Signed-off-by: Jiayuan Chen Signed-off-by: Martin KaFai Lau Reviewed-by: Jakub Sitnicki Acked-by: John Fastabend Link: https://patch.msgid.link/20250122100917.49845-3-mrpre@163.com --- include/linux/skmsg.h | 2 ++ include/net/tcp.h | 8 ++++++++ net/core/skmsg.c | 7 +++++++ net/ipv4/tcp.c | 29 ++++++++++++++++++++++++----- net/ipv4/tcp_bpf.c | 36 ++++++++++++++++++++++++++++++++++++ 5 files changed, 77 insertions(+), 5 deletions(-) (limited to 'include/net') diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h index 2cbe0c22a32f..0b9095a281b8 100644 --- a/include/linux/skmsg.h +++ b/include/linux/skmsg.h @@ -91,6 +91,8 @@ struct sk_psock { struct sk_psock_progs progs; #if IS_ENABLED(CONFIG_BPF_STREAM_PARSER) struct strparser strp; + u32 copied_seq; + u32 ingress_bytes; #endif struct sk_buff_head ingress_skb; struct list_head ingress_msg; diff --git a/include/net/tcp.h b/include/net/tcp.h index 5b2b04835688..9c044fb9ab26 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -729,6 +729,9 @@ void tcp_get_info(struct sock *, struct tcp_info *); /* Read 'sendfile()'-style from a TCP socket */ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc, sk_read_actor_t recv_actor); +int tcp_read_sock_noack(struct sock *sk, read_descriptor_t *desc, + sk_read_actor_t recv_actor, bool noack, + u32 *copied_seq); int tcp_read_skb(struct sock *sk, skb_read_actor_t recv_actor); struct sk_buff *tcp_recv_skb(struct sock *sk, u32 seq, u32 *off); void tcp_read_done(struct sock *sk, size_t len); @@ -2599,6 +2602,11 @@ struct sk_psock; #ifdef CONFIG_BPF_SYSCALL int tcp_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore); void tcp_bpf_clone(const struct sock *sk, struct sock *newsk); +#ifdef CONFIG_BPF_STREAM_PARSER +struct strparser; +int tcp_bpf_strp_read_sock(struct strparser *strp, read_descriptor_t *desc, + sk_read_actor_t recv_actor); +#endif /* CONFIG_BPF_STREAM_PARSER */ #endif /* CONFIG_BPF_SYSCALL */ #ifdef CONFIG_INET diff --git a/net/core/skmsg.c b/net/core/skmsg.c index 61f3f3d4e528..0ddc4c718833 100644 --- a/net/core/skmsg.c +++ b/net/core/skmsg.c @@ -549,6 +549,9 @@ static int sk_psock_skb_ingress_enqueue(struct sk_buff *skb, return num_sge; } +#if IS_ENABLED(CONFIG_BPF_STREAM_PARSER) + psock->ingress_bytes += len; +#endif copied = len; msg->sg.start = 0; msg->sg.size = copied; @@ -1144,6 +1147,10 @@ int sk_psock_init_strp(struct sock *sk, struct sk_psock *psock) if (!ret) sk_psock_set_state(psock, SK_PSOCK_RX_STRP_ENABLED); + if (sk_is_tcp(sk)) { + psock->strp.cb.read_sock = tcp_bpf_strp_read_sock; + psock->copied_seq = tcp_sk(sk)->copied_seq; + } return ret; } diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 0d704bda6c41..285678d8ce07 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1565,12 +1565,13 @@ EXPORT_SYMBOL(tcp_recv_skb); * or for 'peeking' the socket using this routine * (although both would be easy to implement). */ -int tcp_read_sock(struct sock *sk, read_descriptor_t *desc, - sk_read_actor_t recv_actor) +static int __tcp_read_sock(struct sock *sk, read_descriptor_t *desc, + sk_read_actor_t recv_actor, bool noack, + u32 *copied_seq) { struct sk_buff *skb; struct tcp_sock *tp = tcp_sk(sk); - u32 seq = tp->copied_seq; + u32 seq = *copied_seq; u32 offset; int copied = 0; @@ -1624,9 +1625,12 @@ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc, tcp_eat_recv_skb(sk, skb); if (!desc->count) break; - WRITE_ONCE(tp->copied_seq, seq); + WRITE_ONCE(*copied_seq, seq); } - WRITE_ONCE(tp->copied_seq, seq); + WRITE_ONCE(*copied_seq, seq); + + if (noack) + goto out; tcp_rcv_space_adjust(sk); @@ -1635,10 +1639,25 @@ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc, tcp_recv_skb(sk, seq, &offset); tcp_cleanup_rbuf(sk, copied); } +out: return copied; } + +int tcp_read_sock(struct sock *sk, read_descriptor_t *desc, + sk_read_actor_t recv_actor) +{ + return __tcp_read_sock(sk, desc, recv_actor, false, + &tcp_sk(sk)->copied_seq); +} EXPORT_SYMBOL(tcp_read_sock); +int tcp_read_sock_noack(struct sock *sk, read_descriptor_t *desc, + sk_read_actor_t recv_actor, bool noack, + u32 *copied_seq) +{ + return __tcp_read_sock(sk, desc, recv_actor, noack, copied_seq); +} + int tcp_read_skb(struct sock *sk, skb_read_actor_t recv_actor) { struct sk_buff *skb; diff --git a/net/ipv4/tcp_bpf.c b/net/ipv4/tcp_bpf.c index 47f65b1b70ca..ba581785adb4 100644 --- a/net/ipv4/tcp_bpf.c +++ b/net/ipv4/tcp_bpf.c @@ -646,6 +646,42 @@ static int tcp_bpf_assert_proto_ops(struct proto *ops) ops->sendmsg == tcp_sendmsg ? 0 : -ENOTSUPP; } +#if IS_ENABLED(CONFIG_BPF_STREAM_PARSER) +int tcp_bpf_strp_read_sock(struct strparser *strp, read_descriptor_t *desc, + sk_read_actor_t recv_actor) +{ + struct sock *sk = strp->sk; + struct sk_psock *psock; + struct tcp_sock *tp; + int copied = 0; + + tp = tcp_sk(sk); + rcu_read_lock(); + psock = sk_psock(sk); + if (WARN_ON_ONCE(!psock)) { + desc->error = -EINVAL; + goto out; + } + + psock->ingress_bytes = 0; + copied = tcp_read_sock_noack(sk, desc, recv_actor, true, + &psock->copied_seq); + if (copied < 0) + goto out; + /* recv_actor may redirect skb to another socket (SK_REDIRECT) or + * just put skb into ingress queue of current socket (SK_PASS). + * For SK_REDIRECT, we need to ack the frame immediately but for + * SK_PASS, we want to delay the ack until tcp_bpf_recvmsg_parser(). + */ + tp->copied_seq = psock->copied_seq - psock->ingress_bytes; + tcp_rcv_space_adjust(sk); + __tcp_cleanup_rbuf(sk, copied - psock->ingress_bytes); +out: + rcu_read_unlock(); + return copied; +} +#endif /* CONFIG_BPF_STREAM_PARSER */ + int tcp_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore) { int family = sk->sk_family == AF_INET6 ? TCP_BPF_IPV6 : TCP_BPF_IPV4; -- cgit v1.2.3 From 482ad2a4ace2740ca0ff1cbc8f3c7f862f3ab507 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 5 Feb 2025 15:51:09 +0000 Subject: net: add dev_net_rcu() helper dev->nd_net can change, readers should either use rcu_read_lock() or RTNL. We currently use a generic helper, dev_net() with no debugging support. We probably have many hidden bugs. Add dev_net_rcu() helper for callers using rcu_read_lock() protection. Signed-off-by: Eric Dumazet Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250205155120.1676781-2-edumazet@google.com Signed-off-by: Jakub Kicinski --- include/linux/netdevice.h | 6 ++++++ include/net/net_namespace.h | 2 +- 2 files changed, 7 insertions(+), 1 deletion(-) (limited to 'include/net') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 03bb584c62cf..c0a86afb85da 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2663,6 +2663,12 @@ struct net *dev_net(const struct net_device *dev) return read_pnet(&dev->nd_net); } +static inline +struct net *dev_net_rcu(const struct net_device *dev) +{ + return read_pnet_rcu(&dev->nd_net); +} + static inline void dev_net_set(struct net_device *dev, struct net *net) { diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h index 0f5eb9db0c62..7ba1402ca779 100644 --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -398,7 +398,7 @@ static inline struct net *read_pnet(const possible_net_t *pnet) #endif } -static inline struct net *read_pnet_rcu(possible_net_t *pnet) +static inline struct net *read_pnet_rcu(const possible_net_t *pnet) { #ifdef CONFIG_NET_NS return rcu_dereference(pnet->net); -- cgit v1.2.3 From 469308552ca4560176cfc100e7ca84add1bebd7c Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 5 Feb 2025 15:51:10 +0000 Subject: ipv4: add RCU protection to ip4_dst_hoplimit() ip4_dst_hoplimit() must use RCU protection to make sure the net structure it reads does not disappear. Fixes: fa50d974d104 ("ipv4: Namespaceify ip_default_ttl sysctl knob") Signed-off-by: Eric Dumazet Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250205155120.1676781-3-edumazet@google.com Signed-off-by: Jakub Kicinski --- include/net/route.h | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'include/net') diff --git a/include/net/route.h b/include/net/route.h index f86775be3e29..c605fd5ec0c0 100644 --- a/include/net/route.h +++ b/include/net/route.h @@ -382,10 +382,15 @@ static inline int inet_iif(const struct sk_buff *skb) static inline int ip4_dst_hoplimit(const struct dst_entry *dst) { int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT); - struct net *net = dev_net(dst->dev); - if (hoplimit == 0) + if (hoplimit == 0) { + const struct net *net; + + rcu_read_lock(); + net = dev_net_rcu(dst->dev); hoplimit = READ_ONCE(net->ipv4.sysctl_ip_default_ttl); + rcu_read_unlock(); + } return hoplimit; } -- cgit v1.2.3 From 071d8012869b6af352acca346ade13e7be90a49f Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 5 Feb 2025 15:51:11 +0000 Subject: ipv4: use RCU protection in ip_dst_mtu_maybe_forward() ip_dst_mtu_maybe_forward() must use RCU protection to make sure the net structure it reads does not disappear. Fixes: f87c10a8aa1e8 ("ipv4: introduce ip_dst_mtu_maybe_forward and protect forwarding path against pmtu spoofing") Signed-off-by: Eric Dumazet Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250205155120.1676781-4-edumazet@google.com Signed-off-by: Jakub Kicinski --- include/net/ip.h | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) (limited to 'include/net') diff --git a/include/net/ip.h b/include/net/ip.h index 9f5e33e371fc..ba7b43447775 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -471,9 +471,12 @@ static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst, bool forwarding) { const struct rtable *rt = dst_rtable(dst); - struct net *net = dev_net(dst->dev); - unsigned int mtu; + unsigned int mtu, res; + struct net *net; + + rcu_read_lock(); + net = dev_net_rcu(dst->dev); if (READ_ONCE(net->ipv4.sysctl_ip_fwd_use_pmtu) || ip_mtu_locked(dst) || !forwarding) { @@ -497,7 +500,11 @@ static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst, out: mtu = min_t(unsigned int, mtu, IP_MAX_MTU); - return mtu - lwtunnel_headroom(dst->lwtstate, mtu); + res = mtu - lwtunnel_headroom(dst->lwtstate, mtu); + + rcu_read_unlock(); + + return res; } static inline unsigned int ip_skb_dst_mtu(struct sock *sk, -- cgit v1.2.3 From 6d0ce46a93135d96b7fa075a94a88fe0da8e8773 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 7 Feb 2025 13:58:38 +0000 Subject: vrf: use RCU protection in l3mdev_l3_out() l3mdev_l3_out() can be called without RCU being held: raw_sendmsg() ip_push_pending_frames() ip_send_skb() ip_local_out() __ip_local_out() l3mdev_ip_out() Add rcu_read_lock() / rcu_read_unlock() pair to avoid a potential UAF. Fixes: a8e3e1a9f020 ("net: l3mdev: Add hook to output path") Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250207135841.1948589-7-edumazet@google.com Signed-off-by: Jakub Kicinski --- include/net/l3mdev.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/net') diff --git a/include/net/l3mdev.h b/include/net/l3mdev.h index 2d6141f28b53..f7fe796e8429 100644 --- a/include/net/l3mdev.h +++ b/include/net/l3mdev.h @@ -198,10 +198,12 @@ struct sk_buff *l3mdev_l3_out(struct sock *sk, struct sk_buff *skb, u16 proto) if (netif_is_l3_slave(dev)) { struct net_device *master; + rcu_read_lock(); master = netdev_master_upper_dev_get_rcu(dev); if (master && master->l3mdev_ops->l3mdev_l3_out) skb = master->l3mdev_ops->l3mdev_l3_out(master, sk, skb, proto); + rcu_read_unlock(); } return skb; -- cgit v1.2.3 From ab4eedb790cae44313759b50fe47da285e2519d5 Mon Sep 17 00:00:00 2001 From: Luiz Augusto von Dentz Date: Thu, 6 Feb 2025 15:54:45 -0500 Subject: Bluetooth: L2CAP: Fix corrupted list in hci_chan_del This fixes the following trace by reworking the locking of l2cap_conn so instead of only locking when changing the chan_l list this promotes chan_lock to a general lock of l2cap_conn so whenever it is being held it would prevents the likes of l2cap_conn_del to run: list_del corruption, ffff888021297e00->prev is LIST_POISON2 (dead000000000122) ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:61! Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 1 UID: 0 PID: 5896 Comm: syz-executor213 Not tainted 6.14.0-rc1-next-20250204-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:__list_del_entry_valid_or_report+0x12c/0x190 lib/list_debug.c:59 Code: 8c 4c 89 fe 48 89 da e8 32 8c 37 fc 90 0f 0b 48 89 df e8 27 9f 14 fd 48 c7 c7 a0 c0 60 8c 4c 89 fe 48 89 da e8 15 8c 37 fc 90 <0f> 0b 4c 89 e7 e8 0a 9f 14 fd 42 80 3c 2b 00 74 08 4c 89 e7 e8 cb RSP: 0018:ffffc90003f6f998 EFLAGS: 00010246 RAX: 000000000000004e RBX: dead000000000122 RCX: 01454d423f7fbf00 RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000 RBP: dffffc0000000000 R08: ffffffff819f077c R09: 1ffff920007eded0 R10: dffffc0000000000 R11: fffff520007eded1 R12: dead000000000122 R13: dffffc0000000000 R14: ffff8880352248d8 R15: ffff888021297e00 FS: 00007f7ace6686c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7aceeeb1d0 CR3: 000000003527c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __list_del_entry_valid include/linux/list.h:124 [inline] __list_del_entry include/linux/list.h:215 [inline] list_del_rcu include/linux/rculist.h:168 [inline] hci_chan_del+0x70/0x1b0 net/bluetooth/hci_conn.c:2858 l2cap_conn_free net/bluetooth/l2cap_core.c:1816 [inline] kref_put include/linux/kref.h:65 [inline] l2cap_conn_put+0x70/0xe0 net/bluetooth/l2cap_core.c:1830 l2cap_sock_shutdown+0xa8a/0x1020 net/bluetooth/l2cap_sock.c:1377 l2cap_sock_release+0x79/0x1d0 net/bluetooth/l2cap_sock.c:1416 __sock_release net/socket.c:642 [inline] sock_close+0xbc/0x240 net/socket.c:1393 __fput+0x3e9/0x9f0 fs/file_table.c:448 task_work_run+0x24f/0x310 kernel/task_work.c:227 ptrace_notify+0x2d2/0x380 kernel/signal.c:2522 ptrace_report_syscall include/linux/ptrace.h:415 [inline] ptrace_report_syscall_exit include/linux/ptrace.h:477 [inline] syscall_exit_work+0xc7/0x1d0 kernel/entry/common.c:173 syscall_exit_to_user_mode_prepare kernel/entry/common.c:200 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:205 [inline] syscall_exit_to_user_mode+0x24a/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7aceeaf449 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 41 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7ace668218 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: fffffffffffffffc RBX: 00007f7acef39328 RCX: 00007f7aceeaf449 RDX: 000000000000000e RSI: 0000000020000100 RDI: 0000000000000004 RBP: 00007f7acef39320 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000004 R14: 00007f7ace668670 R15: 000000000000000b Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__list_del_entry_valid_or_report+0x12c/0x190 lib/list_debug.c:59 Code: 8c 4c 89 fe 48 89 da e8 32 8c 37 fc 90 0f 0b 48 89 df e8 27 9f 14 fd 48 c7 c7 a0 c0 60 8c 4c 89 fe 48 89 da e8 15 8c 37 fc 90 <0f> 0b 4c 89 e7 e8 0a 9f 14 fd 42 80 3c 2b 00 74 08 4c 89 e7 e8 cb RSP: 0018:ffffc90003f6f998 EFLAGS: 00010246 RAX: 000000000000004e RBX: dead000000000122 RCX: 01454d423f7fbf00 RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000 RBP: dffffc0000000000 R08: ffffffff819f077c R09: 1ffff920007eded0 R10: dffffc0000000000 R11: fffff520007eded1 R12: dead000000000122 R13: dffffc0000000000 R14: ffff8880352248d8 R15: ffff888021297e00 FS: 00007f7ace6686c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7acef05b08 CR3: 000000003527c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Reported-by: syzbot+10bd8fe6741eedd2be2e@syzkaller.appspotmail.com Tested-by: syzbot+10bd8fe6741eedd2be2e@syzkaller.appspotmail.com Fixes: b4f82f9ed43a ("Bluetooth: L2CAP: Fix slab-use-after-free Read in l2cap_send_cmd") Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Dan Carpenter --- include/net/bluetooth/l2cap.h | 3 +- net/bluetooth/l2cap_core.c | 138 +++++++++++++++--------------------------- net/bluetooth/l2cap_sock.c | 15 +++-- 3 files changed, 58 insertions(+), 98 deletions(-) (limited to 'include/net') diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h index d9c767cf773d..9189354c568f 100644 --- a/include/net/bluetooth/l2cap.h +++ b/include/net/bluetooth/l2cap.h @@ -668,7 +668,7 @@ struct l2cap_conn { struct l2cap_chan *smp; struct list_head chan_l; - struct mutex chan_lock; + struct mutex lock; struct kref ref; struct list_head users; }; @@ -970,6 +970,7 @@ void l2cap_chan_del(struct l2cap_chan *chan, int err); void l2cap_send_conn_req(struct l2cap_chan *chan); struct l2cap_conn *l2cap_conn_get(struct l2cap_conn *conn); +struct l2cap_conn *l2cap_conn_hold_unless_zero(struct l2cap_conn *conn); void l2cap_conn_put(struct l2cap_conn *conn); int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user); diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index adb8c33ac595..fec11e576f31 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -119,7 +119,6 @@ static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn, { struct l2cap_chan *c; - mutex_lock(&conn->chan_lock); c = __l2cap_get_chan_by_scid(conn, cid); if (c) { /* Only lock if chan reference is not 0 */ @@ -127,7 +126,6 @@ static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn, if (c) l2cap_chan_lock(c); } - mutex_unlock(&conn->chan_lock); return c; } @@ -140,7 +138,6 @@ static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn, { struct l2cap_chan *c; - mutex_lock(&conn->chan_lock); c = __l2cap_get_chan_by_dcid(conn, cid); if (c) { /* Only lock if chan reference is not 0 */ @@ -148,7 +145,6 @@ static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn, if (c) l2cap_chan_lock(c); } - mutex_unlock(&conn->chan_lock); return c; } @@ -418,7 +414,7 @@ static void l2cap_chan_timeout(struct work_struct *work) if (!conn) return; - mutex_lock(&conn->chan_lock); + mutex_lock(&conn->lock); /* __set_chan_timer() calls l2cap_chan_hold(chan) while scheduling * this work. No need to call l2cap_chan_hold(chan) here again. */ @@ -439,7 +435,7 @@ static void l2cap_chan_timeout(struct work_struct *work) l2cap_chan_unlock(chan); l2cap_chan_put(chan); - mutex_unlock(&conn->chan_lock); + mutex_unlock(&conn->lock); } struct l2cap_chan *l2cap_chan_create(void) @@ -641,9 +637,9 @@ void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan) void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan) { - mutex_lock(&conn->chan_lock); + mutex_lock(&conn->lock); __l2cap_chan_add(conn, chan); - mutex_unlock(&conn->chan_lock); + mutex_unlock(&conn->lock); } void l2cap_chan_del(struct l2cap_chan *chan, int err) @@ -731,9 +727,9 @@ void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func, if (!conn) return; - mutex_lock(&conn->chan_lock); + mutex_lock(&conn->lock); __l2cap_chan_list(conn, func, data); - mutex_unlock(&conn->chan_lock); + mutex_unlock(&conn->lock); } EXPORT_SYMBOL_GPL(l2cap_chan_list); @@ -745,7 +741,7 @@ static void l2cap_conn_update_id_addr(struct work_struct *work) struct hci_conn *hcon = conn->hcon; struct l2cap_chan *chan; - mutex_lock(&conn->chan_lock); + mutex_lock(&conn->lock); list_for_each_entry(chan, &conn->chan_l, list) { l2cap_chan_lock(chan); @@ -754,7 +750,7 @@ static void l2cap_conn_update_id_addr(struct work_struct *work) l2cap_chan_unlock(chan); } - mutex_unlock(&conn->chan_lock); + mutex_unlock(&conn->lock); } static void l2cap_chan_le_connect_reject(struct l2cap_chan *chan) @@ -1507,8 +1503,6 @@ static void l2cap_conn_start(struct l2cap_conn *conn) BT_DBG("conn %p", conn); - mutex_lock(&conn->chan_lock); - list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) { l2cap_chan_lock(chan); @@ -1577,8 +1571,6 @@ static void l2cap_conn_start(struct l2cap_conn *conn) l2cap_chan_unlock(chan); } - - mutex_unlock(&conn->chan_lock); } static void l2cap_le_conn_ready(struct l2cap_conn *conn) @@ -1624,7 +1616,7 @@ static void l2cap_conn_ready(struct l2cap_conn *conn) if (hcon->type == ACL_LINK) l2cap_request_info(conn); - mutex_lock(&conn->chan_lock); + mutex_lock(&conn->lock); list_for_each_entry(chan, &conn->chan_l, list) { @@ -1642,7 +1634,7 @@ static void l2cap_conn_ready(struct l2cap_conn *conn) l2cap_chan_unlock(chan); } - mutex_unlock(&conn->chan_lock); + mutex_unlock(&conn->lock); if (hcon->type == LE_LINK) l2cap_le_conn_ready(conn); @@ -1657,14 +1649,10 @@ static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err) BT_DBG("conn %p", conn); - mutex_lock(&conn->chan_lock); - list_for_each_entry(chan, &conn->chan_l, list) { if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags)) l2cap_chan_set_err(chan, err); } - - mutex_unlock(&conn->chan_lock); } static void l2cap_info_timeout(struct work_struct *work) @@ -1675,7 +1663,9 @@ static void l2cap_info_timeout(struct work_struct *work) conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE; conn->info_ident = 0; + mutex_lock(&conn->lock); l2cap_conn_start(conn); + mutex_unlock(&conn->lock); } /* @@ -1767,6 +1757,8 @@ static void l2cap_conn_del(struct hci_conn *hcon, int err) BT_DBG("hcon %p conn %p, err %d", hcon, conn, err); + mutex_lock(&conn->lock); + kfree_skb(conn->rx_skb); skb_queue_purge(&conn->pending_rx); @@ -1785,8 +1777,6 @@ static void l2cap_conn_del(struct hci_conn *hcon, int err) /* Force the connection to be immediately dropped */ hcon->disc_timeout = 0; - mutex_lock(&conn->chan_lock); - /* Kill channels */ list_for_each_entry_safe(chan, l, &conn->chan_l, list) { l2cap_chan_hold(chan); @@ -1800,12 +1790,14 @@ static void l2cap_conn_del(struct hci_conn *hcon, int err) l2cap_chan_put(chan); } - mutex_unlock(&conn->chan_lock); - if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) cancel_delayed_work_sync(&conn->info_timer); + hci_chan_del(conn->hchan); + conn->hchan = NULL; + hcon->l2cap_data = NULL; + mutex_unlock(&conn->lock); l2cap_conn_put(conn); } @@ -1813,7 +1805,6 @@ static void l2cap_conn_free(struct kref *ref) { struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref); - hci_chan_del(conn->hchan); hci_conn_put(conn->hcon); kfree(conn); } @@ -2924,8 +2915,6 @@ static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb) BT_DBG("conn %p", conn); - mutex_lock(&conn->chan_lock); - list_for_each_entry(chan, &conn->chan_l, list) { if (chan->chan_type != L2CAP_CHAN_RAW) continue; @@ -2940,8 +2929,6 @@ static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb) if (chan->ops->recv(chan, nskb)) kfree_skb(nskb); } - - mutex_unlock(&conn->chan_lock); } /* ---- L2CAP signalling commands ---- */ @@ -3960,7 +3947,6 @@ static void l2cap_connect(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, goto response; } - mutex_lock(&conn->chan_lock); l2cap_chan_lock(pchan); /* Check if the ACL is secure enough (if not SDP) */ @@ -4067,7 +4053,6 @@ response: } l2cap_chan_unlock(pchan); - mutex_unlock(&conn->chan_lock); l2cap_chan_put(pchan); } @@ -4106,27 +4091,19 @@ static int l2cap_connect_create_rsp(struct l2cap_conn *conn, BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x", dcid, scid, result, status); - mutex_lock(&conn->chan_lock); - if (scid) { chan = __l2cap_get_chan_by_scid(conn, scid); - if (!chan) { - err = -EBADSLT; - goto unlock; - } + if (!chan) + return -EBADSLT; } else { chan = __l2cap_get_chan_by_ident(conn, cmd->ident); - if (!chan) { - err = -EBADSLT; - goto unlock; - } + if (!chan) + return -EBADSLT; } chan = l2cap_chan_hold_unless_zero(chan); - if (!chan) { - err = -EBADSLT; - goto unlock; - } + if (!chan) + return -EBADSLT; err = 0; @@ -4164,9 +4141,6 @@ static int l2cap_connect_create_rsp(struct l2cap_conn *conn, l2cap_chan_unlock(chan); l2cap_chan_put(chan); -unlock: - mutex_unlock(&conn->chan_lock); - return err; } @@ -4454,11 +4428,7 @@ static inline int l2cap_disconnect_req(struct l2cap_conn *conn, chan->ops->set_shutdown(chan); - l2cap_chan_unlock(chan); - mutex_lock(&conn->chan_lock); - l2cap_chan_lock(chan); l2cap_chan_del(chan, ECONNRESET); - mutex_unlock(&conn->chan_lock); chan->ops->close(chan); @@ -4495,11 +4465,7 @@ static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn, return 0; } - l2cap_chan_unlock(chan); - mutex_lock(&conn->chan_lock); - l2cap_chan_lock(chan); l2cap_chan_del(chan, 0); - mutex_unlock(&conn->chan_lock); chan->ops->close(chan); @@ -4697,13 +4663,9 @@ static int l2cap_le_connect_rsp(struct l2cap_conn *conn, BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x", dcid, mtu, mps, credits, result); - mutex_lock(&conn->chan_lock); - chan = __l2cap_get_chan_by_ident(conn, cmd->ident); - if (!chan) { - err = -EBADSLT; - goto unlock; - } + if (!chan) + return -EBADSLT; err = 0; @@ -4751,9 +4713,6 @@ static int l2cap_le_connect_rsp(struct l2cap_conn *conn, l2cap_chan_unlock(chan); -unlock: - mutex_unlock(&conn->chan_lock); - return err; } @@ -4865,7 +4824,6 @@ static int l2cap_le_connect_req(struct l2cap_conn *conn, goto response; } - mutex_lock(&conn->chan_lock); l2cap_chan_lock(pchan); if (!smp_sufficient_security(conn->hcon, pchan->sec_level, @@ -4931,7 +4889,6 @@ static int l2cap_le_connect_req(struct l2cap_conn *conn, response_unlock: l2cap_chan_unlock(pchan); - mutex_unlock(&conn->chan_lock); l2cap_chan_put(pchan); if (result == L2CAP_CR_PEND) @@ -5065,7 +5022,6 @@ static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn, goto response; } - mutex_lock(&conn->chan_lock); l2cap_chan_lock(pchan); if (!smp_sufficient_security(conn->hcon, pchan->sec_level, @@ -5140,7 +5096,6 @@ static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn, unlock: l2cap_chan_unlock(pchan); - mutex_unlock(&conn->chan_lock); l2cap_chan_put(pchan); response: @@ -5177,8 +5132,6 @@ static inline int l2cap_ecred_conn_rsp(struct l2cap_conn *conn, BT_DBG("mtu %u mps %u credits %u result 0x%4.4x", mtu, mps, credits, result); - mutex_lock(&conn->chan_lock); - cmd_len -= sizeof(*rsp); list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) { @@ -5264,8 +5217,6 @@ static inline int l2cap_ecred_conn_rsp(struct l2cap_conn *conn, l2cap_chan_unlock(chan); } - mutex_unlock(&conn->chan_lock); - return err; } @@ -5378,8 +5329,6 @@ static inline int l2cap_le_command_rej(struct l2cap_conn *conn, if (cmd_len < sizeof(*rej)) return -EPROTO; - mutex_lock(&conn->chan_lock); - chan = __l2cap_get_chan_by_ident(conn, cmd->ident); if (!chan) goto done; @@ -5394,7 +5343,6 @@ static inline int l2cap_le_command_rej(struct l2cap_conn *conn, l2cap_chan_put(chan); done: - mutex_unlock(&conn->chan_lock); return 0; } @@ -6849,8 +6797,12 @@ static void process_pending_rx(struct work_struct *work) BT_DBG(""); + mutex_lock(&conn->lock); + while ((skb = skb_dequeue(&conn->pending_rx))) l2cap_recv_frame(conn, skb); + + mutex_unlock(&conn->lock); } static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon) @@ -6889,7 +6841,7 @@ static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon) conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR; mutex_init(&conn->ident_lock); - mutex_init(&conn->chan_lock); + mutex_init(&conn->lock); INIT_LIST_HEAD(&conn->chan_l); INIT_LIST_HEAD(&conn->users); @@ -7080,7 +7032,7 @@ int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid, } } - mutex_lock(&conn->chan_lock); + mutex_lock(&conn->lock); l2cap_chan_lock(chan); if (cid && __l2cap_get_chan_by_dcid(conn, cid)) { @@ -7121,7 +7073,7 @@ int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid, chan_unlock: l2cap_chan_unlock(chan); - mutex_unlock(&conn->chan_lock); + mutex_unlock(&conn->lock); done: hci_dev_unlock(hdev); hci_dev_put(hdev); @@ -7333,7 +7285,7 @@ static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt) BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt); - mutex_lock(&conn->chan_lock); + mutex_lock(&conn->lock); list_for_each_entry(chan, &conn->chan_l, list) { l2cap_chan_lock(chan); @@ -7407,7 +7359,7 @@ static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt) l2cap_chan_unlock(chan); } - mutex_unlock(&conn->chan_lock); + mutex_unlock(&conn->lock); } /* Append fragment into frame respecting the maximum len of rx_skb */ @@ -7474,8 +7426,11 @@ static void l2cap_recv_reset(struct l2cap_conn *conn) conn->rx_len = 0; } -static struct l2cap_conn *l2cap_conn_hold_unless_zero(struct l2cap_conn *c) +struct l2cap_conn *l2cap_conn_hold_unless_zero(struct l2cap_conn *c) { + if (!c) + return NULL; + BT_DBG("conn %p orig refcnt %u", c, kref_read(&c->ref)); if (!kref_get_unless_zero(&c->ref)) @@ -7501,11 +7456,15 @@ void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags) hci_dev_unlock(hcon->hdev); - if (!conn) - goto drop; + if (!conn) { + kfree_skb(skb); + return; + } BT_DBG("conn %p len %u flags 0x%x", conn, skb->len, flags); + mutex_lock(&conn->lock); + switch (flags) { case ACL_START: case ACL_START_NO_FLUSH: @@ -7530,7 +7489,7 @@ void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags) if (len == skb->len) { /* Complete frame received */ l2cap_recv_frame(conn, skb); - return; + goto unlock; } BT_DBG("Start: total len %d, frag len %u", len, skb->len); @@ -7592,10 +7551,11 @@ void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags) break; } - l2cap_conn_put(conn); - drop: kfree_skb(skb); +unlock: + mutex_unlock(&conn->lock); + l2cap_conn_put(conn); } static struct hci_cb l2cap_cb = { diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c index 46ea0bee2259..acd11b268b98 100644 --- a/net/bluetooth/l2cap_sock.c +++ b/net/bluetooth/l2cap_sock.c @@ -1326,9 +1326,10 @@ static int l2cap_sock_shutdown(struct socket *sock, int how) /* prevent sk structure from being freed whilst unlocked */ sock_hold(sk); - chan = l2cap_pi(sk)->chan; /* prevent chan structure from being freed whilst unlocked */ - l2cap_chan_hold(chan); + chan = l2cap_chan_hold_unless_zero(l2cap_pi(sk)->chan); + if (!chan) + goto shutdown_already; BT_DBG("chan %p state %s", chan, state_to_string(chan->state)); @@ -1358,22 +1359,20 @@ static int l2cap_sock_shutdown(struct socket *sock, int how) release_sock(sk); l2cap_chan_lock(chan); - conn = chan->conn; - if (conn) - /* prevent conn structure from being freed */ - l2cap_conn_get(conn); + /* prevent conn structure from being freed */ + conn = l2cap_conn_hold_unless_zero(chan->conn); l2cap_chan_unlock(chan); if (conn) /* mutex lock must be taken before l2cap_chan_lock() */ - mutex_lock(&conn->chan_lock); + mutex_lock(&conn->lock); l2cap_chan_lock(chan); l2cap_chan_close(chan, 0); l2cap_chan_unlock(chan); if (conn) { - mutex_unlock(&conn->chan_lock); + mutex_unlock(&conn->lock); l2cap_conn_put(conn); } -- cgit v1.2.3 From e57a6320215c3967f51ab0edeff87db2095440e4 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Mon, 17 Feb 2025 11:11:27 -0800 Subject: net: Add net_passive_inc() and net_passive_dec(). net_drop_ns() is NULL when CONFIG_NET_NS is disabled. The next patch introduces a function that increments and decrements net->passive. As a prep, let's rename and export net_free() to net_passive_dec() and add net_passive_inc(). Suggested-by: Eric Dumazet Link: https://lore.kernel.org/netdev/CANn89i+oUCt2VGvrbrweniTendZFEh+nwS=uonc004-aPkWy-Q@mail.gmail.com/ Signed-off-by: Kuniyuki Iwashima Reviewed-by: Eric Dumazet Link: https://patch.msgid.link/20250217191129.19967-2-kuniyu@amazon.com Signed-off-by: Jakub Kicinski --- include/net/net_namespace.h | 11 +++++++++++ net/core/net_namespace.c | 8 ++++---- 2 files changed, 15 insertions(+), 4 deletions(-) (limited to 'include/net') diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h index 7ba1402ca779..f467a66abc6b 100644 --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -297,6 +297,7 @@ static inline int check_net(const struct net *net) } void net_drop_ns(void *); +void net_passive_dec(struct net *net); #else @@ -326,8 +327,18 @@ static inline int check_net(const struct net *net) } #define net_drop_ns NULL + +static inline void net_passive_dec(struct net *net) +{ + refcount_dec(&net->passive); +} #endif +static inline void net_passive_inc(struct net *net) +{ + refcount_inc(&net->passive); +} + /* Returns true if the netns initialization is completed successfully */ static inline bool net_initialized(const struct net *net) { diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index cb39a12b2f82..4303f2a49262 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -464,7 +464,7 @@ static void net_complete_free(void) } -static void net_free(struct net *net) +void net_passive_dec(struct net *net) { if (refcount_dec_and_test(&net->passive)) { kfree(rcu_access_pointer(net->gen)); @@ -482,7 +482,7 @@ void net_drop_ns(void *p) struct net *net = (struct net *)p; if (net) - net_free(net); + net_passive_dec(net); } struct net *copy_net_ns(unsigned long flags, @@ -523,7 +523,7 @@ put_userns: key_remove_domain(net->key_domain); #endif put_user_ns(user_ns); - net_free(net); + net_passive_dec(net); dec_ucounts: dec_net_namespaces(ucounts); return ERR_PTR(rv); @@ -672,7 +672,7 @@ static void cleanup_net(struct work_struct *work) key_remove_domain(net->key_domain); #endif put_user_ns(net->user_ns); - net_free(net); + net_passive_dec(net); } cleanup_net_task = NULL; } -- cgit v1.2.3 From 9b6412e6979f6f9e0632075f8f008937b5cd4efd Mon Sep 17 00:00:00 2001 From: Sabrina Dubroca Date: Mon, 17 Feb 2025 11:23:35 +0100 Subject: tcp: drop secpath at the same time as we currently drop dst Xiumei reported hitting the WARN in xfrm6_tunnel_net_exit while running tests that boil down to: - create a pair of netns - run a basic TCP test over ipcomp6 - delete the pair of netns The xfrm_state found on spi_byaddr was not deleted at the time we delete the netns, because we still have a reference on it. This lingering reference comes from a secpath (which holds a ref on the xfrm_state), which is still attached to an skb. This skb is not leaked, it ends up on sk_receive_queue and then gets defer-free'd by skb_attempt_defer_free. The problem happens when we defer freeing an skb (push it on one CPU's defer_list), and don't flush that list before the netns is deleted. In that case, we still have a reference on the xfrm_state that we don't expect at this point. We already drop the skb's dst in the TCP receive path when it's no longer needed, so let's also drop the secpath. At this point, tcp_filter has already called into the LSM hooks that may require the secpath, so it should not be needed anymore. However, in some of those places, the MPTCP extension has just been attached to the skb, so we cannot simply drop all extensions. Fixes: 68822bdf76f1 ("net: generalize skb freeing deferral to per-cpu lists") Reported-by: Xiumei Mu Signed-off-by: Sabrina Dubroca Reviewed-by: Eric Dumazet Link: https://patch.msgid.link/5055ba8f8f72bdcb602faa299faca73c280b7735.1739743613.git.sd@queasysnail.net Signed-off-by: Paolo Abeni --- include/net/tcp.h | 14 ++++++++++++++ net/ipv4/tcp_fastopen.c | 4 ++-- net/ipv4/tcp_input.c | 8 ++++---- net/ipv4/tcp_ipv4.c | 2 +- 4 files changed, 21 insertions(+), 7 deletions(-) (limited to 'include/net') diff --git a/include/net/tcp.h b/include/net/tcp.h index 5b2b04835688..930cda5b5eb9 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -41,6 +41,7 @@ #include #include #include +#include #include #include @@ -683,6 +684,19 @@ void tcp_fin(struct sock *sk); void tcp_check_space(struct sock *sk); void tcp_sack_compress_send_ack(struct sock *sk); +static inline void tcp_cleanup_skb(struct sk_buff *skb) +{ + skb_dst_drop(skb); + secpath_reset(skb); +} + +static inline void tcp_add_receive_queue(struct sock *sk, struct sk_buff *skb) +{ + DEBUG_NET_WARN_ON_ONCE(skb_dst(skb)); + DEBUG_NET_WARN_ON_ONCE(secpath_exists(skb)); + __skb_queue_tail(&sk->sk_receive_queue, skb); +} + /* tcp_timer.c */ void tcp_init_xmit_timers(struct sock *); static inline void tcp_clear_xmit_timers(struct sock *sk) diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c index 0f523cbfe329..32b28fc21b63 100644 --- a/net/ipv4/tcp_fastopen.c +++ b/net/ipv4/tcp_fastopen.c @@ -178,7 +178,7 @@ void tcp_fastopen_add_skb(struct sock *sk, struct sk_buff *skb) if (!skb) return; - skb_dst_drop(skb); + tcp_cleanup_skb(skb); /* segs_in has been initialized to 1 in tcp_create_openreq_child(). * Hence, reset segs_in to 0 before calling tcp_segs_in() * to avoid double counting. Also, tcp_segs_in() expects @@ -195,7 +195,7 @@ void tcp_fastopen_add_skb(struct sock *sk, struct sk_buff *skb) TCP_SKB_CB(skb)->tcp_flags &= ~TCPHDR_SYN; tp->rcv_nxt = TCP_SKB_CB(skb)->end_seq; - __skb_queue_tail(&sk->sk_receive_queue, skb); + tcp_add_receive_queue(sk, skb); tp->syn_data_acked = 1; /* u64_stats_update_begin(&tp->syncp) not needed here, diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 98b8cc740392..0cbf81bf3d45 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -4976,7 +4976,7 @@ static void tcp_ofo_queue(struct sock *sk) tcp_rcv_nxt_update(tp, TCP_SKB_CB(skb)->end_seq); fin = TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN; if (!eaten) - __skb_queue_tail(&sk->sk_receive_queue, skb); + tcp_add_receive_queue(sk, skb); else kfree_skb_partial(skb, fragstolen); @@ -5168,7 +5168,7 @@ static int __must_check tcp_queue_rcv(struct sock *sk, struct sk_buff *skb, skb, fragstolen)) ? 1 : 0; tcp_rcv_nxt_update(tcp_sk(sk), TCP_SKB_CB(skb)->end_seq); if (!eaten) { - __skb_queue_tail(&sk->sk_receive_queue, skb); + tcp_add_receive_queue(sk, skb); skb_set_owner_r(skb, sk); } return eaten; @@ -5251,7 +5251,7 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb) __kfree_skb(skb); return; } - skb_dst_drop(skb); + tcp_cleanup_skb(skb); __skb_pull(skb, tcp_hdr(skb)->doff * 4); reason = SKB_DROP_REASON_NOT_SPECIFIED; @@ -6232,7 +6232,7 @@ void tcp_rcv_established(struct sock *sk, struct sk_buff *skb) NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPHPHITS); /* Bulk data transfer: receiver */ - skb_dst_drop(skb); + tcp_cleanup_skb(skb); __skb_pull(skb, tcp_header_len); eaten = tcp_queue_rcv(sk, skb, &fragstolen); diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index cc2b5194a18d..2632844d2c35 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -2027,7 +2027,7 @@ bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb, */ skb_condense(skb); - skb_dst_drop(skb); + tcp_cleanup_skb(skb); if (unlikely(tcp_checksum_complete(skb))) { bh_unlock_sock(sk); -- cgit v1.2.3 From 14ad6ed30a10afbe91b0749d6378285f4225d482 Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Tue, 18 Feb 2025 19:29:39 +0100 Subject: net: allow small head cache usage with large MAX_SKB_FRAGS values Sabrina reported the following splat: WARNING: CPU: 0 PID: 1 at net/core/dev.c:6935 netif_napi_add_weight_locked+0x8f2/0xba0 Modules linked in: CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.14.0-rc1-net-00092-g011b03359038 #996 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014 RIP: 0010:netif_napi_add_weight_locked+0x8f2/0xba0 Code: e8 c3 e6 6a fe 48 83 c4 28 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc c7 44 24 10 ff ff ff ff e9 8f fb ff ff e8 9e e6 6a fe <0f> 0b e9 d3 fe ff ff e8 92 e6 6a fe 48 8b 04 24 be ff ff ff ff 48 RSP: 0000:ffffc9000001fc60 EFLAGS: 00010293 RAX: 0000000000000000 RBX: ffff88806ce48128 RCX: 1ffff11001664b9e RDX: ffff888008f00040 RSI: ffffffff8317ca42 RDI: ffff88800b325cb6 RBP: ffff88800b325c40 R08: 0000000000000001 R09: ffffed100167502c R10: ffff88800b3a8163 R11: 0000000000000000 R12: ffff88800ac1c168 R13: ffff88800ac1c168 R14: ffff88800ac1c168 R15: 0000000000000007 FS: 0000000000000000(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff888008201000 CR3: 0000000004c94001 CR4: 0000000000370ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: gro_cells_init+0x1ba/0x270 xfrm_input_init+0x4b/0x2a0 xfrm_init+0x38/0x50 ip_rt_init+0x2d7/0x350 ip_init+0xf/0x20 inet_init+0x406/0x590 do_one_initcall+0x9d/0x2e0 do_initcalls+0x23b/0x280 kernel_init_freeable+0x445/0x490 kernel_init+0x20/0x1d0 ret_from_fork+0x46/0x80 ret_from_fork_asm+0x1a/0x30 irq event stamp: 584330 hardirqs last enabled at (584338): [] __up_console_sem+0x77/0xb0 hardirqs last disabled at (584345): [] __up_console_sem+0x5c/0xb0 softirqs last enabled at (583242): [] netlink_insert+0x14d/0x470 softirqs last disabled at (583754): [] netif_napi_add_weight_locked+0x77d/0xba0 on kernel built with MAX_SKB_FRAGS=45, where SKB_WITH_OVERHEAD(1024) is smaller than GRO_MAX_HEAD. Such built additionally contains the revert of the single page frag cache so that napi_get_frags() ends up using the page frag allocator, triggering the splat. Note that the underlying issue is independent from the mentioned revert; address it ensuring that the small head cache will fit either TCP and GRO allocation and updating napi_alloc_skb() and __netdev_alloc_skb() to select kmalloc() usage for any allocation fitting such cache. Reported-by: Sabrina Dubroca Suggested-by: Eric Dumazet Fixes: 3948b05950fd ("net: introduce a config option to tweak MAX_SKB_FRAGS") Reviewed-by: Eric Dumazet Signed-off-by: Paolo Abeni --- include/net/gro.h | 3 +++ net/core/gro.c | 3 --- net/core/skbuff.c | 10 +++++++--- 3 files changed, 10 insertions(+), 6 deletions(-) (limited to 'include/net') diff --git a/include/net/gro.h b/include/net/gro.h index b9b58c1f8d19..7b548f91754b 100644 --- a/include/net/gro.h +++ b/include/net/gro.h @@ -11,6 +11,9 @@ #include #include +/* This should be increased if a protocol with a bigger head is added. */ +#define GRO_MAX_HEAD (MAX_HEADER + 128) + struct napi_gro_cb { union { struct { diff --git a/net/core/gro.c b/net/core/gro.c index d1f44084e978..78b320b63174 100644 --- a/net/core/gro.c +++ b/net/core/gro.c @@ -7,9 +7,6 @@ #define MAX_GRO_SKBS 8 -/* This should be increased if a protocol with a bigger head is added. */ -#define GRO_MAX_HEAD (MAX_HEADER + 128) - static DEFINE_SPINLOCK(offload_lock); /** diff --git a/net/core/skbuff.c b/net/core/skbuff.c index a441613a1e6c..f5a6d50570c4 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -69,6 +69,7 @@ #include #include #include +#include #include #include #include @@ -95,7 +96,9 @@ static struct kmem_cache *skbuff_ext_cache __ro_after_init; #endif -#define SKB_SMALL_HEAD_SIZE SKB_HEAD_ALIGN(MAX_TCP_HEADER) +#define GRO_MAX_HEAD_PAD (GRO_MAX_HEAD + NET_SKB_PAD + NET_IP_ALIGN) +#define SKB_SMALL_HEAD_SIZE SKB_HEAD_ALIGN(max(MAX_TCP_HEADER, \ + GRO_MAX_HEAD_PAD)) /* We want SKB_SMALL_HEAD_CACHE_SIZE to not be a power of two. * This should ensure that SKB_SMALL_HEAD_HEADROOM is a unique @@ -736,7 +739,7 @@ struct sk_buff *__netdev_alloc_skb(struct net_device *dev, unsigned int len, /* If requested length is either too small or too big, * we use kmalloc() for skb->head allocation. */ - if (len <= SKB_WITH_OVERHEAD(1024) || + if (len <= SKB_WITH_OVERHEAD(SKB_SMALL_HEAD_CACHE_SIZE) || len > SKB_WITH_OVERHEAD(PAGE_SIZE) || (gfp_mask & (__GFP_DIRECT_RECLAIM | GFP_DMA))) { skb = __alloc_skb(len, gfp_mask, SKB_ALLOC_RX, NUMA_NO_NODE); @@ -816,7 +819,8 @@ struct sk_buff *napi_alloc_skb(struct napi_struct *napi, unsigned int len) * When the small frag allocator is available, prefer it over kmalloc * for small fragments */ - if ((!NAPI_HAS_SMALL_PAGE_FRAG && len <= SKB_WITH_OVERHEAD(1024)) || + if ((!NAPI_HAS_SMALL_PAGE_FRAG && + len <= SKB_WITH_OVERHEAD(SKB_SMALL_HEAD_CACHE_SIZE)) || len > SKB_WITH_OVERHEAD(PAGE_SIZE) || (gfp_mask & (__GFP_DIRECT_RECLAIM | GFP_DMA))) { skb = __alloc_skb(len, gfp_mask, SKB_ALLOC_RX | SKB_ALLOC_NAPI, -- cgit v1.2.3