pm24.git/net/ipv4/ip_sockglue.c, branch rust-6.8

net: bpf: Use sockopt_lock_sock() in ip_sock_set_tos()

2023-10-27T22:41:28Z

With latest sync from net-next tree, bpf-next has a bpf selftest failure: [root@arch-fb-vm1 bpf]# ./test_progs -t setget_sockopt ... [ 76.194349] ============================================ [ 76.194682] WARNING: possible recursive locking detected [ 76.195039] 6.6.0-rc7-g37884503df08-dirty #67 Tainted: G W OE [ 76.195518] -------------------------------------------- [ 76.195852] new_name/154 is trying to acquire lock: [ 76.196159] ffff8c3e06ad8d30 (sk_lock-AF_INET){+.+.}-{0:0}, at: ip_sock_set_tos+0x19/0x30 [ 76.196669] [ 76.196669] but task is already holding lock: [ 76.197028] ffff8c3e06ad8d30 (sk_lock-AF_INET){+.+.}-{0:0}, at: inet_listen+0x21/0x70 [ 76.197517] [ 76.197517] other info that might help us debug this: [ 76.197919] Possible unsafe locking scenario: [ 76.197919] [ 76.198287] CPU0 [ 76.198444] ---- [ 76.198600] lock(sk_lock-AF_INET); [ 76.198831] lock(sk_lock-AF_INET); [ 76.199062] [ 76.199062] *** DEADLOCK *** [ 76.199062] [ 76.199420] May be due to missing lock nesting notation [ 76.199420] [ 76.199879] 2 locks held by new_name/154: [ 76.200131] #0: ffff8c3e06ad8d30 (sk_lock-AF_INET){+.+.}-{0:0}, at: inet_listen+0x21/0x70 [ 76.200644] #1: ffffffff90f96a40 (rcu_read_lock){....}-{1:2}, at: __cgroup_bpf_run_filter_sock_ops+0x55/0x290 [ 76.201268] [ 76.201268] stack backtrace: [ 76.201538] CPU: 4 PID: 154 Comm: new_name Tainted: G W OE 6.6.0-rc7-g37884503df08-dirty #67 [ 76.202134] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 [ 76.202699] Call Trace: [ 76.202858] [ 76.203002] dump_stack_lvl+0x4b/0x80 [ 76.203239] __lock_acquire+0x740/0x1ec0 [ 76.203503] lock_acquire+0xc1/0x2a0 [ 76.203766] ? ip_sock_set_tos+0x19/0x30 [ 76.204050] ? sk_stream_write_space+0x12a/0x230 [ 76.204389] ? lock_release+0xbe/0x260 [ 76.204661] lock_sock_nested+0x32/0x80 [ 76.204942] ? ip_sock_set_tos+0x19/0x30 [ 76.205208] ip_sock_set_tos+0x19/0x30 [ 76.205452] do_ip_setsockopt+0x4b3/0x1580 [ 76.205719] __bpf_setsockopt+0x62/0xa0 [ 76.205963] bpf_sock_ops_setsockopt+0x11/0x20 [ 76.206247] bpf_prog_630217292049c96e_bpf_test_sockopt_int+0xbc/0x123 [ 76.206660] bpf_prog_493685a3bae00bbd_bpf_test_ip_sockopt+0x49/0x4b [ 76.207055] bpf_prog_b0bcd27f269aeea0_skops_sockopt+0x44c/0xec7 [ 76.207437] __cgroup_bpf_run_filter_sock_ops+0xda/0x290 [ 76.207829] __inet_listen_sk+0x108/0x1b0 [ 76.208122] inet_listen+0x48/0x70 [ 76.208373] __sys_listen+0x74/0xb0 [ 76.208630] __x64_sys_listen+0x16/0x20 [ 76.208911] do_syscall_64+0x3f/0x90 [ 76.209174] entry_SYSCALL_64_after_hwframe+0x6e/0xd8 ... Both ip_sock_set_tos() and inet_listen() calls lock_sock(sk) which caused a dead lock. To fix the issue, use sockopt_lock_sock() in ip_sock_set_tos() instead. sockopt_lock_sock() will avoid lock_sock() if it is in bpf context. Fixes: 878d951c6712 ("inet: lock the socket in ip_sock_set_tos()") Suggested-by: Martin KaFai Lau Signed-off-by: Yonghong Song Reviewed-by: Eric Dumazet Link: https://lore.kernel.org/r/20231027182424.1444845-1-yonghong.song@linux.dev Signed-off-by: Jakub Kicinski

inet: lock the socket in ip_sock_set_tos()

2023-10-19T11:13:13Z

Christoph Paasch reported a panic in TCP stack [1] Indeed, we should not call sk_dst_reset() without holding the socket lock, as __sk_dst_get() callers do not all rely on bare RCU. [1] BUG: kernel NULL pointer dereference, address: 0000000000000000 PGD 12bad6067 P4D 12bad6067 PUD 12bad5067 PMD 0 Oops: 0000 [#1] PREEMPT SMP CPU: 1 PID: 2750 Comm: syz-executor.5 Not tainted 6.6.0-rc4-g7a5720a344e7 #49 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014 RIP: 0010:tcp_get_metrics+0x118/0x8f0 net/ipv4/tcp_metrics.c:321 Code: c7 44 24 70 02 00 8b 03 89 44 24 48 c7 44 24 4c 00 00 00 00 66 c7 44 24 58 02 00 66 ba 02 00 b1 01 89 4c 24 04 4c 89 7c 24 10 <49> 8b 0f 48 8b 89 50 05 00 00 48 89 4c 24 30 33 81 00 02 00 00 69 RSP: 0018:ffffc90000af79b8 EFLAGS: 00010293 RAX: 000000000100007f RBX: ffff88812ae8f500 RCX: ffff88812b5f8f01 RDX: 0000000000000002 RSI: ffffffff8300f080 RDI: 0000000000000002 RBP: 0000000000000002 R08: 0000000000000003 R09: ffffffff8205eca0 R10: 0000000000000002 R11: ffff88812b5f8f00 R12: ffff88812a9e0580 R13: 0000000000000000 R14: ffff88812ae8fbd2 R15: 0000000000000000 FS: 00007f70a006b640(0000) GS:ffff88813bd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000012bad7003 CR4: 0000000000170ee0 Call Trace: tcp_fastopen_cache_get+0x32/0x140 net/ipv4/tcp_metrics.c:567 tcp_fastopen_cookie_check+0x28/0x180 net/ipv4/tcp_fastopen.c:419 tcp_connect+0x9c8/0x12a0 net/ipv4/tcp_output.c:3839 tcp_v4_connect+0x645/0x6e0 net/ipv4/tcp_ipv4.c:323 __inet_stream_connect+0x120/0x590 net/ipv4/af_inet.c:676 tcp_sendmsg_fastopen+0x2d6/0x3a0 net/ipv4/tcp.c:1021 tcp_sendmsg_locked+0x1957/0x1b00 net/ipv4/tcp.c:1073 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1336 __sock_sendmsg+0x83/0xd0 net/socket.c:730 __sys_sendto+0x20a/0x2a0 net/socket.c:2194 __do_sys_sendto net/socket.c:2206 [inline] Fixes: e08d0b3d1723 ("inet: implement lockless IP_TOS") Reported-by: Christoph Paasch Signed-off-by: Eric Dumazet Link: https://lore.kernel.org/r/20231018090014.345158-1-edumazet@google.com Signed-off-by: Paolo Abeni

inet: implement lockless getsockopt(IP_MULTICAST_IF)

2023-10-01T18:39:19Z

Add missing annotations to inet->mc_index and inet->mc_addr to fix data-races. getsockopt(IP_MULTICAST_IF) can be lockless. setsockopt() side is left for later. Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Signed-off-by: David S. Miller

inet: lockless IP_PKTOPTIONS implementation

2023-10-01T18:39:19Z

Current implementation is already lockless, because the socket lock is released before reading socket fields. Add missing READ_ONCE() annotations. Note that corresponding WRITE_ONCE() are needed, the order of the patches do not really matter. Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Signed-off-by: David S. Miller

inet: implement lockless getsockopt(IP_UNICAST_IF)

2023-10-01T18:39:19Z

Add missing READ_ONCE() annotations when reading inet->uc_index Implementing getsockopt(IP_UNICAST_IF) locklessly seems possible, the setsockopt() part might not be possible at the moment. Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Signed-off-by: David S. Miller

inet: lockless getsockopt(IP_MTU)

2023-10-01T18:39:19Z

sk_dst_get() does not require socket lock. Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Signed-off-by: David S. Miller

inet: lockless getsockopt(IP_OPTIONS)

2023-10-01T18:39:18Z

inet->inet_opt being RCU protected, we can use RCU instead of locking the socket. Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Signed-off-by: David S. Miller

inet: implement lockless IP_TOS

2023-10-01T18:39:18Z

Some reads of inet->tos are racy. Add needed READ_ONCE() annotations and convert IP_TOS option lockless. v2: missing changes in include/net/route.h (David Ahern) Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Signed-off-by: David S. Miller

inet: implement lockless IP_MTU_DISCOVER

2023-10-01T18:39:18Z

inet->pmtudisc can be read locklessly. Implement proper lockless reads and writes to inet->pmtudisc ip_sock_set_mtu_discover() can now be called from arbitrary contexts. Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Signed-off-by: David S. Miller

inet: implement lockless IP_MULTICAST_TTL

2023-10-01T18:39:18Z

inet->mc_ttl can be read locklessly. Implement proper lockless reads and writes to inet->mc_ttl Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Signed-off-by: David S. Miller