[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 39.341077][ T23] audit: type=1800 audit(1570220271.369:25): pid=7061 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 39.360717][ T23] audit: type=1800 audit(1570220271.369:26): pid=7061 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 39.427941][ T23] audit: type=1800 audit(1570220271.449:27): pid=7061 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2469 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.10.19' (ECDSA) to the list of known hosts. 2019/10/04 20:18:01 fuzzer started 2019/10/04 20:18:01 dialing manager at 10.128.0.105:44881 2019/10/04 20:18:01 syscalls: 2523 2019/10/04 20:18:01 code coverage: enabled 2019/10/04 20:18:01 comparison tracing: enabled 2019/10/04 20:18:01 extra coverage: extra coverage is not supported by the kernel 2019/10/04 20:18:01 setuid sandbox: enabled 2019/10/04 20:18:01 namespace sandbox: enabled 2019/10/04 20:18:01 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/04 20:18:01 fault injection: enabled 2019/10/04 20:18:01 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/04 20:18:01 net packet injection: enabled 2019/10/04 20:18:01 net device setup: enabled 2019/10/04 20:18:01 concurrency sanitizer: enabled syzkaller login: [ 50.115231][ T7215] ================================================================== [ 50.123425][ T7215] BUG: KCSAN: data-race in __zone_watermark_ok / get_page_from_freelist [ 50.131723][ T7215] [ 50.134037][ T7215] read to 0xffff88812fffcf58 of 8 bytes by interrupt on cpu 0: [ 50.141566][ T7215] __zone_watermark_ok+0x106/0x240 [ 50.146665][ T7215] get_page_from_freelist+0x629/0x2300 [ 50.152120][ T7215] __alloc_pages_nodemask+0x255/0x4d0 [ 50.157492][ T7215] alloc_pages_current+0xd1/0x170 [ 50.162511][ T7215] skb_page_frag_refill+0x16f/0x260 [ 50.167710][ T7215] try_fill_recv+0x51f/0xdc0 [ 50.172286][ T7215] virtnet_poll+0x64c/0x7d0 [ 50.176771][ T7215] net_rx_action+0x3ae/0xa50 [ 50.181369][ T7215] __do_softirq+0x115/0x33f [ 50.185861][ T7215] irq_exit+0xbb/0xe0 [ 50.189828][ T7215] do_IRQ+0xdf/0x150 [ 50.193707][ T7215] ret_from_intr+0x0/0x19 [ 50.198043][ T7215] native_safe_halt+0xe/0x10 [ 50.202618][ T7215] arch_cpu_idle+0x1f/0x30 [ 50.207008][ T7215] [ 50.209325][ T7215] write to 0xffff88812fffcf58 of 8 bytes by task 7215 on cpu 1: [ 50.221294][ T7215] get_page_from_freelist+0x1217/0x2300 [ 50.226827][ T7215] __alloc_pages_nodemask+0x255/0x4d0 [ 50.232179][ T7215] alloc_pages_vma+0x15b/0x2b0 [ 50.236927][ T7215] __handle_mm_fault+0x17ac/0x2d00 [ 50.242024][ T7215] handle_mm_fault+0x21b/0x520 [ 50.246776][ T7215] __do_page_fault+0x3fb/0x9e0 [ 50.251523][ T7215] do_page_fault+0x54/0x233 [ 50.256007][ T7215] page_fault+0x34/0x40 [ 50.260136][ T7215] [ 50.262446][ T7215] Reported by Kernel Concurrency Sanitizer on: [ 50.268592][ T7215] CPU: 1 PID: 7215 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 50.275678][ T7215] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.285726][ T7215] ================================================================== [ 50.293769][ T7215] Kernel panic - not syncing: panic_on_warn set ... [ 50.300342][ T7215] CPU: 1 PID: 7215 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 50.307426][ T7215] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.317471][ T7215] Call Trace: [ 50.320760][ T7215] dump_stack+0xf5/0x159 [ 50.325007][ T7215] panic+0x209/0x639 [ 50.328900][ T7215] ? vprintk_func+0x8d/0x140 [ 50.333485][ T7215] kcsan_report.cold+0x57/0xeb [ 50.338257][ T7215] __kcsan_setup_watchpoint+0x342/0x500 [ 50.343801][ T7215] __tsan_write8+0x32/0x40 [ 50.348213][ T7215] get_page_from_freelist+0x1217/0x2300 [ 50.353768][ T7215] __alloc_pages_nodemask+0x255/0x4d0 [ 50.359135][ T7215] alloc_pages_vma+0x15b/0x2b0 [ 50.363889][ T7215] __handle_mm_fault+0x17ac/0x2d00 [ 50.368997][ T7215] handle_mm_fault+0x21b/0x520 [ 50.373753][ T7215] __do_page_fault+0x3fb/0x9e0 [ 50.378510][ T7215] do_page_fault+0x54/0x233 [ 50.383020][ T7215] ? prepare_exit_to_usermode+0x154/0x1a0 [ 50.388750][ T7215] page_fault+0x34/0x40 [ 50.392889][ T7215] RIP: 0033:0x45a2a3 [ 50.396772][ T7215] Code: 00 48 81 eb 00 01 00 00 48 81 c7 00 01 00 00 48 81 fb 00 01 00 00 73 82 e9 07 ff ff ff c5 fd ef c0 48 81 fb 00 00 00 02 73 46 fe 7f 07 c5 fe 7f 47 20 c5 fe 7f 47 40 c5 fe 7f 47 60 48 81 eb [ 50.416358][ T7215] RSP: 002b:000000c42004df08 EFLAGS: 00010202 [ 50.422403][ T7215] RAX: 0000000000000000 RBX: 000000000003a000 RCX: 0000000000102000 [ 50.430361][ T7215] RDX: 0000000000000000 RSI: 0000000000000081 RDI: 000000c42087c000 [ 50.438329][ T7215] RBP: 000000c42004df50 R08: 000000c000000000 R09: 000000000000045a [ 50.446298][ T7215] R10: 000000c42004dd98 R11: 000000c42004dd90 R12: 000000000000011e [ 50.454253][ T7215] R13: 000000000000011d R14: 0000000000000200 R15: ffffffffffffffff [ 51.593680][ T7215] Shutting down cpus with NMI [ 51.599684][ T7215] Kernel Offset: disabled [ 51.604007][ T7215] Rebooting in 86400 seconds..