RIP: 0010:synchronize_rcu+0x0/0x360 kernel/rcu/tree.c:4010 Code: e1 07 80 c1 03 38 c1 0f 8c 97 fe ff ff 4c 89 f7 e8 65 38 81 00 e9 8a fe ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 RSP: f620:0000000000000206 EFLAGS: 1ffff920005dfec0 ================================================================== BUG: KASAN: stack-out-of-bounds in __show_regs+0xa6/0x610 arch/x86/kernel/process_64.c:83 Read of size 8 at addr ffffc90002eff578 by task syz.4.1205/12111 CPU: 1 UID: 0 PID: 12111 Comm: syz.4.1205 Not tainted 6.11.0-rc1-next-20240729-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 __show_regs+0xa6/0x610 arch/x86/kernel/process_64.c:83 show_trace_log_lvl+0x3d4/0x520 arch/x86/kernel/dumpstack.c:301 sched_show_task+0x506/0x6d0 kernel/sched/core.c:7512 report_rtnl_holders+0x327/0x400 net/core/rtnetlink.c:110 call_timer_fn+0x18e/0x650 kernel/time/timer.c:1792 expire_timers kernel/time/timer.c:1843 [inline] __run_timers kernel/time/timer.c:2417 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2428 run_timer_base kernel/time/timer.c:2437 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2447 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__outw arch/x86/include/asm/shared/io.h:23 [inline] RIP: 0010:iowrite16+0x37/0x90 lib/iomap.c:213 Code: f3 db fc 48 81 fb 00 00 04 00 72 0a e8 02 f3 db fc 66 89 2b eb 59 48 81 fb 01 00 01 00 72 0d e8 ef f2 db fc 89 e8 89 da 66 ef 43 8b 2d 01 e4 4c 0a 31 ff 89 ee e8 18 f7 db fc 85 ed 74 2b e8 RSP: 0018:ffffc9000eff7928 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 000000000001c0b0 RCX: 0000000000040000 RDX: 000000000001c0b0 RSI: 000000000003ffff RDI: 0000000000040000 RBP: 0000000000000000 R08: ffffffff852a4aa0 R09: ffff88801ff8e998 R10: dffffc0000000000 R11: ffffffff852ba0c0 R12: dffffc0000000000 R13: 00000000000074d7 R14: dffffc0000000000 R15: ffff88801fcf0e00 vp_notify+0x57/0x80 drivers/virtio/virtio_pci_common.c:45 virtqueue_notify drivers/virtio/virtio_ring.c:2370 [inline] virtqueue_kick+0x39b/0x5c0 drivers/virtio/virtio_ring.c:2393 request_entropy drivers/char/hw_random/virtio-rng.c:63 [inline] copy_data+0x237/0x370 drivers/char/hw_random/virtio-rng.c:74 virtio_read+0xcb/0x200 drivers/char/hw_random/virtio-rng.c:92 rng_get_data drivers/char/hw_random/core.c:185 [inline] rng_dev_read+0x248/0x6d0 drivers/char/hw_random/core.c:223 do_loop_readv_writev fs/read_write.c:761 [inline] vfs_readv+0x6c2/0xa90 fs/read_write.c:934 do_preadv fs/read_write.c:1049 [inline] __do_sys_preadv fs/read_write.c:1099 [inline] __se_sys_preadv fs/read_write.c:1094 [inline] __x64_sys_preadv+0x1c7/0x2d0 fs/read_write.c:1094 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb6fa9773b9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb6fb688048 EFLAGS: 00000246 ORIG_RAX: 0000000000000127 RAX: ffffffffffffffda RBX: 00007fb6fab05f80 RCX: 00007fb6fa9773b9 RDX: 0000000000000001 RSI: 0000000020000240 RDI: 0000000000000004 RBP: 00007fb6fa9e48e6 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fb6fab05f80 R15: 00007fffc8d0fed8 The buggy address belongs to the virtual mapping at [ffffc90002ef8000, ffffc90002f01000) created by: copy_process+0x5d1/0x3d90 kernel/fork.c:2206 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1c386 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_NOWARN|__GFP_ZERO), pid 12, tgid 12 (kworker/u8:1), ts 6741943460, free_ts 6619353307 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1493 prep_new_page mm/page_alloc.c:1501 [inline] get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3442 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4700 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2263 vm_area_alloc_pages mm/vmalloc.c:3584 [inline] __vmalloc_area_node mm/vmalloc.c:3660 [inline] __vmalloc_node_range_noprof+0x971/0x1460 mm/vmalloc.c:3841 alloc_thread_stack_node kernel/fork.c:314 [inline] dup_task_struct+0x444/0x8c0 kernel/fork.c:1115 copy_process+0x5d1/0x3d90 kernel/fork.c:2206 kernel_clone+0x226/0x8f0 kernel/fork.c:2788 user_mode_thread+0x132/0x1a0 kernel/fork.c:2866 call_usermodehelper_exec_work+0x5c/0x230 kernel/umh.c:172 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:144 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 page last free pid 59 tgid 59 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1094 [inline] free_unref_page+0xd22/0xea0 mm/page_alloc.c:2612 vfree+0x186/0x2e0 mm/vmalloc.c:3364 delayed_vfree_work+0x56/0x80 mm/vmalloc.c:3285 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:144 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Memory state around the buggy address: ffffc90002eff400: f2 f2 00 00 00 00 00 00 f2 f2 f2 f2 00 00 00 00 ffffc90002eff480: 00 f3 f3 f3 f3 f3 f3 f3 00 00 00 00 00 00 00 00 >ffffc90002eff500: 00 00 00 00 f1 f1 f1 f1 00 f2 f2 f2 00 f3 f3 f3 ^ ffffc90002eff580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc90002eff600: f1 f1 f1 f1 00 f2 f2 f2 00 f3 f3 f3 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: e1 07 loope 0x9 2: 80 c1 03 add $0x3,%cl 5: 38 c1 cmp %al,%cl 7: 0f 8c 97 fe ff ff jl 0xfffffea4 d: 4c 89 f7 mov %r14,%rdi 10: e8 65 38 81 00 call 0x81387a 15: e9 8a fe ff ff jmp 0xfffffea4 1a: 90 nop 1b: 90 nop 1c: 90 nop 1d: 90 nop 1e: 90 nop 1f: 90 nop 20: 90 nop 21: 90 nop 22: 90 nop 23: 90 nop 24: 90 nop 25: 90 nop 26: 90 nop 27: 90 nop 28: 90 nop 29: 90 nop * 2a: f3 0f 1e fa endbr64 <-- trapping instruction 2e: 55 push %rbp 2f: 48 89 e5 mov %rsp,%rbp 32: 41 57 push %r15 34: 41 56 push %r14 36: 41 55 push %r13 38: 41 54 push %r12 3a: 53 push %rbx 3b: 48 83 e4 e0 and $0xffffffffffffffe0,%rsp 3f: 48 rex.W