74df0319e4
[ Upstream commit dc9511dd6f37fe803f6b15b61b030728d7057417 ] sk->sk_wmem_queued can be read locklessly from sctp_poll() Use sk_wmem_queued_add() when the field is changed, and add READ_ONCE() annotations in sctp_writeable() and sctp_assocs_seq_show() syzbot reported: BUG: KCSAN: data-race in sctp_poll / sctp_wfree read-write to 0xffff888149d77810 of 4 bytes by interrupt on cpu 0: sctp_wfree+0x170/0x4a0 net/sctp/socket.c:9147 skb_release_head_state+0xb7/0x1a0 net/core/skbuff.c:988 skb_release_all net/core/skbuff.c:1000 [inline] __kfree_skb+0x16/0x140 net/core/skbuff.c:1016 consume_skb+0x57/0x180 net/core/skbuff.c:1232 sctp_chunk_destroy net/sctp/sm_make_chunk.c:1503 [inline] sctp_chunk_put+0xcd/0x130 net/sctp/sm_make_chunk.c:1530 sctp_datamsg_put+0x29a/0x300 net/sctp/chunk.c:128 sctp_chunk_free+0x34/0x50 net/sctp/sm_make_chunk.c:1515 sctp_outq_sack+0xafa/0xd70 net/sctp/outqueue.c:1381 sctp_cmd_process_sack net/sctp/sm_sideeffect.c:834 [inline] sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1366 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1198 [inline] sctp_do_sm+0x12c7/0x31b0 net/sctp/sm_sideeffect.c:1169 sctp_assoc_bh_rcv+0x2b2/0x430 net/sctp/associola.c:1051 sctp_inq_push+0x108/0x120 net/sctp/inqueue.c:80 sctp_rcv+0x116e/0x1340 net/sctp/input.c:243 sctp6_rcv+0x25/0x40 net/sctp/ipv6.c:1120 ip6_protocol_deliver_rcu+0x92f/0xf30 net/ipv6/ip6_input.c:437 ip6_input_finish net/ipv6/ip6_input.c:482 [inline] NF_HOOK include/linux/netfilter.h:303 [inline] ip6_input+0xbd/0x1b0 net/ipv6/ip6_input.c:491 dst_input include/net/dst.h:468 [inline] ip6_rcv_finish+0x1e2/0x2e0 net/ipv6/ip6_input.c:79 NF_HOOK include/linux/netfilter.h:303 [inline] ipv6_rcv+0x74/0x150 net/ipv6/ip6_input.c:309 __netif_receive_skb_one_core net/core/dev.c:5452 [inline] __netif_receive_skb+0x90/0x1b0 net/core/dev.c:5566 process_backlog+0x21f/0x380 net/core/dev.c:5894 __napi_poll+0x60/0x3b0 net/core/dev.c:6460 napi_poll net/core/dev.c:6527 [inline] net_rx_action+0x32b/0x750 net/core/dev.c:6660 __do_softirq+0xc1/0x265 kernel/softirq.c:553 run_ksoftirqd+0x17/0x20 kernel/softirq.c:921 smpboot_thread_fn+0x30a/0x4a0 kernel/smpboot.c:164 kthread+0x1d7/0x210 kernel/kthread.c:389 ret_from_fork+0x2e/0x40 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 read to 0xffff888149d77810 of 4 bytes by task 17828 on cpu 1: sctp_writeable net/sctp/socket.c:9304 [inline] sctp_poll+0x265/0x410 net/sctp/socket.c:8671 sock_poll+0x253/0x270 net/socket.c:1374 vfs_poll include/linux/poll.h:88 [inline] do_pollfd fs/select.c:873 [inline] do_poll fs/select.c:921 [inline] do_sys_poll+0x636/0xc00 fs/select.c:1015 __do_sys_ppoll fs/select.c:1121 [inline] __se_sys_ppoll+0x1af/0x1f0 fs/select.c:1101 __x64_sys_ppoll+0x67/0x80 fs/select.c:1101 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0x00019e80 -> 0x0000cc80 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 17828 Comm: syz-executor.1 Not tainted 6.5.0-rc7-syzkaller-00185-g28f20a19294d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Xin Long <lucien.xin@gmail.com> Link: https://lore.kernel.org/r/20230830094519.950007-1-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.