kernel/net/ipv4/tcp_ipv4.c, branch linux-6.2.y

bpf: tcp: Use sock_gen_put instead of sock_put in bpf_iter_tcp

2023-04-20T10:36:53Z

[ Upstream commit 580031ff9952b7dbf48dedba6b56a100ae002bef ] While reviewing the udp-iter batching patches, noticed the bpf_iter_tcp calling sock_put() is incorrect. It should call sock_gen_put instead because bpf_iter_tcp is iterating the ehash table which has the req sk and tw sk. This patch replaces all sock_put with sock_gen_put in the bpf_iter_tcp codepath. Fixes: 04c7820b776f ("bpf: tcp: Bpf iter batching and lock_sock") Signed-off-by: Martin KaFai Lau Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20230328004232.2134233-1-martin.lau@linux.dev Signed-off-by: Sasha Levin

tcp: use 2-arg optimal variant of kfree_rcu()

2022-12-03T04:44:45Z

kfree_rcu(1-arg) should be avoided as much as possible, since this is only possible from sleepable contexts, and incurr extra rcu barriers. I wish the 1-arg variant of kfree_rcu() would get a distinct name, like kfree_rcu_slow() to avoid it being abused. Fixes: 459837b522f7 ("net/tcp: Disable TCP-MD5 static key on tcp_md5sig_info destruction") Signed-off-by: Eric Dumazet Cc: Paul E. McKenney Reviewed-by: Pavan Chebbi Reviewed-by: Dmitry Safonov Link: https://lore.kernel.org/r/20221202052847.2623997-1-edumazet@google.com Signed-off-by: Jakub Kicinski

net/tcp: Do cleanup on tcp_md5_key_copy() failure

2022-12-01T23:53:05Z

If the kernel was short on (atomic) memory and failed to allocate it - don't proceed to creation of request socket. Otherwise the socket would be unsigned and userspace likely doesn't expect that the TCP is not MD5-signed anymore. Signed-off-by: Dmitry Safonov Acked-by: Jakub Kicinski Reviewed-by: Eric Dumazet Signed-off-by: Jakub Kicinski

net/tcp: Disable TCP-MD5 static key on tcp_md5sig_info destruction

2022-12-01T23:53:05Z

To do that, separate two scenarios: - where it's the first MD5 key on the system, which means that enabling of the static key may need to sleep; - copying of an existing key from a listening socket to the request socket upon receiving a signed TCP segment, where static key was already enabled (when the key was added to the listening socket). Now the life-time of the static branch for TCP-MD5 is until: - last tcp_md5sig_info is destroyed - last socket in time-wait state with MD5 key is closed. Which means that after all sockets with TCP-MD5 keys are gone, the system gets back the performance of disabled md5-key static branch. While at here, provide static_key_fast_inc() helper that does ref counter increment in atomic fashion (without grabbing cpus_read_lock() on CONFIG_JUMP_LABEL=y). This is needed to add a new user for a static_key when the caller controls the lifetime of another user. Signed-off-by: Dmitry Safonov Acked-by: Jakub Kicinski Reviewed-by: Eric Dumazet Signed-off-by: Jakub Kicinski

net/tcp: Separate tcp_md5sig_info allocation into tcp_md5sig_info_add()

2022-12-01T23:53:05Z

Add a helper to allocate tcp_md5sig_info, that will help later to do/allocate things when info allocated, once per socket. Signed-off-by: Dmitry Safonov Reviewed-by: Eric Dumazet Acked-by: Jakub Kicinski Signed-off-by: Jakub Kicinski

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2022-11-29T21:04:52Z

tools/lib/bpf/ringbuf.c 927cbb478adf ("libbpf: Handle size overflow for ringbuf mmap") b486d19a0ab0 ("libbpf: checkpatch: Fixed code alignments in ringbuf.c") https://lore.kernel.org/all/20221121122707.44d1446a@canb.auug.org.au/ Signed-off-by: Jakub Kicinski

dccp/tcp: Fixup bhash2 bucket when connect() fails.

2022-11-23T04:15:37Z

If a socket bound to a wildcard address fails to connect(), we only reset saddr and keep the port. Then, we have to fix up the bhash2 bucket; otherwise, the bucket has an inconsistent address in the list. Also, listen() for such a socket will fire the WARN_ON() in inet_csk_get_port(). [0] Note that when a system runs out of memory, we give up fixing the bucket and unlink sk from bhash and bhash2 by inet_put_port(). [0]: WARNING: CPU: 0 PID: 207 at net/ipv4/inet_connection_sock.c:548 inet_csk_get_port (net/ipv4/inet_connection_sock.c:548 (discriminator 1)) Modules linked in: CPU: 0 PID: 207 Comm: bhash2_prev_rep Not tainted 6.1.0-rc3-00799-gc8421681c845 #63 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-1.amzn2022.0.1 04/01/2014 RIP: 0010:inet_csk_get_port (net/ipv4/inet_connection_sock.c:548 (discriminator 1)) Code: 74 a7 eb 93 48 8b 54 24 18 0f b7 cb 4c 89 e6 4c 89 ff e8 48 b2 ff ff 49 8b 87 18 04 00 00 e9 32 ff ff ff 0f 0b e9 34 ff ff ff <0f> 0b e9 42 ff ff ff 41 8b 7f 50 41 8b 4f 54 89 fe 81 f6 00 00 ff RSP: 0018:ffffc900003d7e50 EFLAGS: 00010202 RAX: ffff8881047fb500 RBX: 0000000000004e20 RCX: 0000000000000000 RDX: 000000000000000a RSI: 00000000fffffe00 RDI: 00000000ffffffff RBP: ffffffff8324dc00 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000001 R14: 0000000000004e20 R15: ffff8881054e1280 FS: 00007f8ac04dc740(0000) GS:ffff88842fc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020001540 CR3: 00000001055fa003 CR4: 0000000000770ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: inet_csk_listen_start (net/ipv4/inet_connection_sock.c:1205) inet_listen (net/ipv4/af_inet.c:228) __sys_listen (net/socket.c:1810) __x64_sys_listen (net/socket.c:1819 net/socket.c:1817 net/socket.c:1817) do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120) RIP: 0033:0x7f8ac051de5d Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 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 8b 0d 93 af 1b 00 f7 d8 64 89 01 48 RSP: 002b:00007ffc1c177248 EFLAGS: 00000206 ORIG_RAX: 0000000000000032 RAX: ffffffffffffffda RBX: 0000000020001550 RCX: 00007f8ac051de5d RDX: ffffffffffffff80 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00007ffc1c177270 R08: 0000000000000018 R09: 0000000000000007 R10: 0000000020001540 R11: 0000000000000206 R12: 00007ffc1c177388 R13: 0000000000401169 R14: 0000000000403e18 R15: 00007f8ac0723000 Fixes: 28044fc1d495 ("net: Add a bhash2 table hashed by port and address") Reported-by: syzbot Reported-by: Mat Martineau Signed-off-by: Kuniyuki Iwashima Acked-by: Joanne Koong Reviewed-by: Eric Dumazet Signed-off-by: Jakub Kicinski

dccp/tcp: Update saddr under bhash's lock.

2022-11-23T04:15:36Z

When we call connect() for a socket bound to a wildcard address, we update saddr locklessly. However, it could result in a data race; another thread iterating over bhash might see a corrupted address. Let's update saddr under the bhash bucket's lock. Fixes: 3df80d9320bc ("[DCCP]: Introduce DCCPv6") Fixes: 7c657876b63c ("[DCCP]: Initial implementation") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima Acked-by: Joanne Koong Reviewed-by: Eric Dumazet Signed-off-by: Jakub Kicinski

dccp/tcp: Reset saddr on failure after inet6?_hash_connect().

2022-11-23T04:15:36Z

When connect() is called on a socket bound to the wildcard address, we change the socket's saddr to a local address. If the socket fails to connect() to the destination, we have to reset the saddr. However, when an error occurs after inet_hash6?_connect() in (dccp|tcp)_v[46]_conect(), we forget to reset saddr and leave the socket bound to the address. From the user's point of view, whether saddr is reset or not varies with errno. Let's fix this inconsistent behaviour. Note that after this patch, the repro [0] will trigger the WARN_ON() in inet_csk_get_port() again, but this patch is not buggy and rather fixes a bug papering over the bhash2's bug for which we need another fix. For the record, the repro causes -EADDRNOTAVAIL in inet_hash6_connect() by this sequence: s1 = socket() s1.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1) s1.bind(('127.0.0.1', 10000)) s1.sendto(b'hello', MSG_FASTOPEN, (('127.0.0.1', 10000))) # or s1.connect(('127.0.0.1', 10000)) s2 = socket() s2.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1) s2.bind(('0.0.0.0', 10000)) s2.connect(('127.0.0.1', 10000)) # -EADDRNOTAVAIL s2.listen(32) # WARN_ON(inet_csk(sk)->icsk_bind2_hash != tb2); [0]: https://syzkaller.appspot.com/bug?extid=015d756bbd1f8b5c8f09 Fixes: 3df80d9320bc ("[DCCP]: Introduce DCCPv6") Fixes: 7c657876b63c ("[DCCP]: Initial implementation") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima Acked-by: Joanne Koong Reviewed-by: Eric Dumazet Signed-off-by: Jakub Kicinski

ipasdv4/tcp_ipv4: remove redundant assignment

2022-11-14T11:20:15Z

The value of 'st->state' has been verified as "TCP_SEQ_STATE_LISTENING", it's unnecessary to assign TCP_SEQ_STATE_LISTENING to it, so we can remove it. Signed-off-by: xu xin Signed-off-by: David S. Miller