================================================================== BUG: KASAN: use-after-free in cpu_map_generic_redirect+0x1c7/0x780 kernel/bpf/cpumap.c:788 Read of size 8 at addr ffff88811ea28618 by task syz.0.1639/4500 CPU: 1 PID: 4500 Comm: syz.0.1639 Not tainted 6.1.90-syzkaller-00030-g370ea8bc2e0b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x151/0x1b7 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0x158/0x4e0 mm/kasan/report.c:427 kasan_report+0x13c/0x170 mm/kasan/report.c:531 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:351 cpu_map_generic_redirect+0x1c7/0x780 kernel/bpf/cpumap.c:788 xdp_do_generic_redirect_map net/core/filter.c:4367 [inline] xdp_do_generic_redirect+0x3b5/0xad0 net/core/filter.c:4412 do_xdp_generic+0x53e/0x800 net/core/dev.c:4954 tun_get_user+0x238a/0x3a90 drivers/net/tun.c:1920 tun_chr_write_iter+0x129/0x210 drivers/net/tun.c:2044 call_write_iter include/linux/fs.h:2274 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x902/0xeb0 fs/read_write.c:584 ksys_write+0x199/0x2c0 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __x64_sys_write+0x7b/0x90 fs/read_write.c:646 x64_sys_call+0x2f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f3d75f7895f Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 c9 8d 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 1c 8e 02 00 48 RSP: 002b:00007f3d76e14000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f3d76115f80 RCX: 00007f3d75f7895f RDX: 0000000000000d86 RSI: 0000000020001580 RDI: 00000000000000c8 RBP: 00007f3d75fe793e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000d86 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f3d76115f80 R15: 00007ffe48f950b8 Allocated by task 319: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_alloc_info+0x1f/0x30 mm/kasan/generic.c:505 ____kasan_kmalloc mm/kasan/common.c:379 [inline] __kasan_kmalloc+0x9c/0xb0 mm/kasan/common.c:388 kasan_kmalloc include/linux/kasan.h:212 [inline] kmalloc_trace+0x44/0xa0 mm/slab_common.c:1052 kmalloc include/linux/slab.h:556 [inline] kzalloc include/linux/slab.h:692 [inline] kernfs_fop_open+0x350/0xb10 fs/kernfs/file.c:666 do_dentry_open+0x891/0x1250 fs/open.c:884 vfs_open+0x73/0x80 fs/open.c:1015 do_open fs/namei.c:3627 [inline] path_openat+0x2532/0x2d60 fs/namei.c:3784 do_filp_open+0x230/0x480 fs/namei.c:3811 do_sys_openat2+0x151/0x890 fs/open.c:1341 do_sys_open fs/open.c:1357 [inline] __do_sys_openat fs/open.c:1373 [inline] __se_sys_openat fs/open.c:1368 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1368 x64_sys_call+0x6bf/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:258 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb4/0xc0 mm/kasan/generic.c:486 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496 insert_work+0x56/0x310 kernel/workqueue.c:1368 __queue_work+0x9b6/0xd70 kernel/workqueue.c:1527 queue_work_on+0x105/0x170 kernel/workqueue.c:1555 queue_work include/linux/workqueue.h:510 [inline] schedule_work include/linux/workqueue.h:571 [inline] __cpu_map_entry_replace kernel/bpf/cpumap.c:558 [inline] cpu_map_free+0x1e7/0x2c0 kernel/bpf/cpumap.c:641 bpf_map_free_deferred+0xf7/0x1b0 kernel/bpf/syscall.c:622 process_one_work+0x73d/0xcb0 kernel/workqueue.c:2299 worker_thread+0xa60/0x1260 kernel/workqueue.c:2446 kthread+0x26d/0x300 kernel/kthread.c:386 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Second to last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb4/0xc0 mm/kasan/generic.c:486 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496 __call_rcu_common kernel/rcu/tree.c:2806 [inline] call_rcu+0xee/0x1340 kernel/rcu/tree.c:2925 __cpu_map_entry_replace kernel/bpf/cpumap.c:556 [inline] cpu_map_free+0x109/0x2c0 kernel/bpf/cpumap.c:641 bpf_map_free_deferred+0xf7/0x1b0 kernel/bpf/syscall.c:622 process_one_work+0x73d/0xcb0 kernel/workqueue.c:2299 worker_thread+0xa60/0x1260 kernel/workqueue.c:2446 kthread+0x26d/0x300 kernel/kthread.c:386 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 The buggy address belongs to the object at ffff88811ea28600 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 24 bytes inside of 192-byte region [ffff88811ea28600, ffff88811ea286c0) The buggy address belongs to the physical page: page:ffffea00047a8a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88811ea28100 pfn:0x11ea28 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 ffffea0004250048 ffffea0004355308 ffff888100042c00 raw: ffff88811ea28100 000000000010000b 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 281, tgid 281 (syz-executor), ts 19987622410, free_ts 19982104739 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x213/0x220 mm/page_alloc.c:2590 prep_new_page+0x1b/0x110 mm/page_alloc.c:2597 get_page_from_freelist+0x27ea/0x2870 mm/page_alloc.c:4425 __alloc_pages+0x3a1/0x780 mm/page_alloc.c:5714 alloc_slab_page+0x6c/0xf0 allocate_slab mm/slub.c:1962 [inline] new_slab+0x90/0x3e0 mm/slub.c:2015 ___slab_alloc+0x6f9/0xb80 mm/slub.c:3203 __slab_alloc+0x5d/0xa0 mm/slub.c:3302 slab_alloc_node mm/slub.c:3387 [inline] __kmem_cache_alloc_node+0x1af/0x250 mm/slub.c:3460 kmalloc_trace+0x2a/0xa0 mm/slab_common.c:1047 kmalloc include/linux/slab.h:556 [inline] kzalloc include/linux/slab.h:692 [inline] alloc_fs_context+0x65/0x830 fs/fs_context.c:257 fs_context_for_mount+0x24/0x30 fs/fs_context.c:304 do_new_mount+0x15c/0xb30 fs/namespace.c:3030 path_mount+0x671/0x1070 fs/namespace.c:3381 do_mount fs/namespace.c:3394 [inline] __do_sys_mount fs/namespace.c:3602 [inline] __se_sys_mount+0x2c4/0x3b0 fs/namespace.c:3579 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3579 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1498 [inline] free_pcp_prepare mm/page_alloc.c:1572 [inline] free_unref_page_prepare+0x83d/0x850 mm/page_alloc.c:3498 free_unref_page+0xb2/0x5c0 mm/page_alloc.c:3594 free_the_page mm/page_alloc.c:798 [inline] __free_pages+0x61/0xf0 mm/page_alloc.c:5803 free_pages+0x7c/0x90 mm/page_alloc.c:5814 _pgd_free arch/x86/mm/pgtable.c:420 [inline] pgd_free+0x17d/0x190 arch/x86/mm/pgtable.c:476 mm_free_pgd kernel/fork.c:833 [inline] __mmdrop+0xb0/0x3e0 kernel/fork.c:884 mmdrop include/linux/sched/mm.h:50 [inline] mmdrop_sched include/linux/sched/mm.h:78 [inline] finish_task_switch+0x2cd/0x7b0 kernel/sched/core.c:5320 context_switch kernel/sched/core.c:5421 [inline] __schedule+0xcaf/0x1550 kernel/sched/core.c:6744 schedule+0xc3/0x180 kernel/sched/core.c:6820 syslog_print+0x256/0x600 kernel/printk/printk.c:1528 do_syslog+0x732/0x7f0 kernel/printk/printk.c:1681 __do_sys_syslog kernel/printk/printk.c:1773 [inline] __se_sys_syslog kernel/printk/printk.c:1771 [inline] __x64_sys_syslog+0x7c/0x90 kernel/printk/printk.c:1771 x64_sys_call+0x2f9/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:104 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff88811ea28500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88811ea28580: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88811ea28600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88811ea28680: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88811ea28700: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== BUG: kernel NULL pointer dereference, address: 0000000000000004 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 1260c9067 P4D 1260c9067 PUD 141544067 PMD 0 Oops: 0002 [#1] PREEMPT SMP KASAN CPU: 1 PID: 4500 Comm: syz.0.1639 Tainted: G B 6.1.90-syzkaller-00030-g370ea8bc2e0b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 RIP: 0010:atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:543 [inline] RIP: 0010:queued_spin_lock include/asm-generic/qspinlock.h:111 [inline] RIP: 0010:do_raw_spin_lock include/linux/spinlock.h:187 [inline] RIP: 0010:__raw_spin_lock include/linux/spinlock_api_smp.h:134 [inline] RIP: 0010:_raw_spin_lock+0xba/0x1b0 kernel/locking/spinlock.c:154 Code: 00 00 e8 59 5f 9d fc 4c 89 ff be 04 00 00 00 e8 4c 5f 9d fc 43 0f b6 04 26 84 c0 0f 85 a9 00 00 00 8b 44 24 20 b9 01 00 00 00 41 0f b1 4d 00 75 33 48 c7 04 24 0e 36 e0 45 49 c7 04 1c 00 00 RSP: 0018:ffffc90000e27680 EFLAGS: 00010297 RAX: 0000000000000000 RBX: 1ffff920001c4ed0 RCX: 0000000000000001 RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90000e276a0 RBP: ffffc90000e27710 R08: dffffc0000000000 R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: dffffc0000000000 R13: 0000000000000004 R14: 1ffff920001c4ed4 R15: ffffc90000e276a0 FS: 00007f3d76e146c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000004 CR3: 0000000128836000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: spin_lock include/linux/spinlock.h:351 [inline] ptr_ring_produce include/linux/ptr_ring.h:128 [inline] cpu_map_generic_redirect+0x1f4/0x780 kernel/bpf/cpumap.c:788 xdp_do_generic_redirect_map net/core/filter.c:4367 [inline] xdp_do_generic_redirect+0x3b5/0xad0 net/core/filter.c:4412 do_xdp_generic+0x53e/0x800 net/core/dev.c:4954 tun_get_user+0x238a/0x3a90 drivers/net/tun.c:1920 tun_chr_write_iter+0x129/0x210 drivers/net/tun.c:2044 call_write_iter include/linux/fs.h:2274 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x902/0xeb0 fs/read_write.c:584 ksys_write+0x199/0x2c0 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __x64_sys_write+0x7b/0x90 fs/read_write.c:646 x64_sys_call+0x2f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f3d75f7895f Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 c9 8d 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 1c 8e 02 00 48 RSP: 002b:00007f3d76e14000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f3d76115f80 RCX: 00007f3d75f7895f RDX: 0000000000000d86 RSI: 0000000020001580 RDI: 00000000000000c8 RBP: 00007f3d75fe793e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000d86 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f3d76115f80 R15: 00007ffe48f950b8 Modules linked in: CR2: 0000000000000004 ---[ end trace 0000000000000000 ]--- RIP: 0010:atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:543 [inline] RIP: 0010:queued_spin_lock include/asm-generic/qspinlock.h:111 [inline] RIP: 0010:do_raw_spin_lock include/linux/spinlock.h:187 [inline] RIP: 0010:__raw_spin_lock include/linux/spinlock_api_smp.h:134 [inline] RIP: 0010:_raw_spin_lock+0xba/0x1b0 kernel/locking/spinlock.c:154 Code: 00 00 e8 59 5f 9d fc 4c 89 ff be 04 00 00 00 e8 4c 5f 9d fc 43 0f b6 04 26 84 c0 0f 85 a9 00 00 00 8b 44 24 20 b9 01 00 00 00 41 0f b1 4d 00 75 33 48 c7 04 24 0e 36 e0 45 49 c7 04 1c 00 00 RSP: 0018:ffffc90000e27680 EFLAGS: 00010297 RAX: 0000000000000000 RBX: 1ffff920001c4ed0 RCX: 0000000000000001 RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90000e276a0 RBP: ffffc90000e27710 R08: dffffc0000000000 R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: dffffc0000000000 R13: 0000000000000004 R14: 1ffff920001c4ed4 R15: ffffc90000e276a0 FS: 00007f3d76e146c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000004 CR3: 0000000128836000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: e8 59 5f 9d fc call 0xfc9d5f60 7: 4c 89 ff mov %r15,%rdi a: be 04 00 00 00 mov $0x4,%esi f: e8 4c 5f 9d fc call 0xfc9d5f60 14: 43 0f b6 04 26 movzbl (%r14,%r12,1),%eax 19: 84 c0 test %al,%al 1b: 0f 85 a9 00 00 00 jne 0xca 21: 8b 44 24 20 mov 0x20(%rsp),%eax 25: b9 01 00 00 00 mov $0x1,%ecx * 2a: f0 41 0f b1 4d 00 lock cmpxchg %ecx,0x0(%r13) <-- trapping instruction 30: 75 33 jne 0x65 32: 48 c7 04 24 0e 36 e0 movq $0x45e0360e,(%rsp) 39: 45 3a: 49 rex.WB 3b: c7 .byte 0xc7 3c: 04 1c add $0x1c,%al