7903311b2c
commit 8a9896177784063d01068293caea3f74f6830ff6 upstream. Another syzbot report [1] is about tp->status lockless reads from __packet_get_status() [1] BUG: KCSAN: data-race in __packet_rcv_has_room / __packet_set_status write to 0xffff888117d7c080 of 8 bytes by interrupt on cpu 0: __packet_set_status+0x78/0xa0 net/packet/af_packet.c:407 tpacket_rcv+0x18bb/0x1a60 net/packet/af_packet.c:2483 deliver_skb net/core/dev.c:2173 [inline] __netif_receive_skb_core+0x408/0x1e80 net/core/dev.c:5337 __netif_receive_skb_one_core net/core/dev.c:5491 [inline] __netif_receive_skb+0x57/0x1b0 net/core/dev.c:5607 process_backlog+0x21f/0x380 net/core/dev.c:5935 __napi_poll+0x60/0x3b0 net/core/dev.c:6498 napi_poll net/core/dev.c:6565 [inline] net_rx_action+0x32b/0x750 net/core/dev.c:6698 __do_softirq+0xc1/0x265 kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x57/0xa0 kernel/softirq.c:650 sysvec_apic_timer_interrupt+0x6d/0x80 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 smpboot_thread_fn+0x33c/0x4a0 kernel/smpboot.c:112 kthread+0x1d7/0x210 kernel/kthread.c:379 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 read to 0xffff888117d7c080 of 8 bytes by interrupt on cpu 1: __packet_get_status net/packet/af_packet.c:436 [inline] packet_lookup_frame net/packet/af_packet.c:524 [inline] __tpacket_has_room net/packet/af_packet.c:1255 [inline] __packet_rcv_has_room+0x3f9/0x450 net/packet/af_packet.c:1298 tpacket_rcv+0x275/0x1a60 net/packet/af_packet.c:2285 deliver_skb net/core/dev.c:2173 [inline] dev_queue_xmit_nit+0x38a/0x5e0 net/core/dev.c:2243 xmit_one net/core/dev.c:3574 [inline] dev_hard_start_xmit+0xcf/0x3f0 net/core/dev.c:3594 __dev_queue_xmit+0xefb/0x1d10 net/core/dev.c:4244 dev_queue_xmit include/linux/netdevice.h:3088 [inline] can_send+0x4eb/0x5d0 net/can/af_can.c:276 bcm_can_tx+0x314/0x410 net/can/bcm.c:302 bcm_tx_timeout_handler+0xdb/0x260 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x217/0x700 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0xd6/0x120 kernel/time/hrtimer.c:1766 __do_softirq+0xc1/0x265 kernel/softirq.c:571 run_ksoftirqd+0x17/0x20 kernel/softirq.c:939 smpboot_thread_fn+0x30a/0x4a0 kernel/smpboot.c:164 kthread+0x1d7/0x210 kernel/kthread.c:379 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 value changed: 0x0000000000000000 -> 0x0000000020000081 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 19 Comm: ksoftirqd/1 Not tainted 6.4.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 Fixes: 69e3c75f4d54 ("net: TX_RING and packet mmap") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://lore.kernel.org/r/20230803145600.2937518-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.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.