================================================================== BUG: KASAN: use-after-free in dev_map_enqueue+0x40/0x340 kernel/bpf/devmap.c:532 Read of size 8 at addr ffff888119107900 by task syz.6.7176/21904 CPU: 0 PID: 21904 Comm: syz.6.7176 Tainted: G W 6.1.129-syzkaller-00055-gca24c52e3c25 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 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 dev_map_enqueue+0x40/0x340 kernel/bpf/devmap.c:532 __xdp_do_redirect_frame net/core/filter.c:4319 [inline] xdp_do_redirect_frame+0x2b5/0x800 net/core/filter.c:4381 xdp_test_run_batch net/bpf/test_run.c:314 [inline] bpf_test_run_xdp_live+0xc30/0x1f70 net/bpf/test_run.c:362 bpf_prog_test_run_xdp+0x7d1/0x1130 net/bpf/test_run.c:1393 bpf_prog_test_run+0x3b0/0x630 kernel/bpf/syscall.c:3670 __sys_bpf+0x59f/0x7f0 kernel/bpf/syscall.c:5025 __do_sys_bpf kernel/bpf/syscall.c:5111 [inline] __se_sys_bpf kernel/bpf/syscall.c:5109 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5109 x64_sys_call+0x87f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:322 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: 0033:0x7f85be58d169 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:00007f85bf36d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f85be7a5fa0 RCX: 00007f85be58d169 RDX: 0000000000000050 RSI: 00002000000000c0 RDI: 000000000000000a RBP: 00007f85be60e730 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f85be7a5fa0 R15: 00007ffcd2929618 Allocated by task 21863: 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] __do_kmalloc_node mm/slab_common.c:938 [inline] __kmalloc_node+0xb4/0x1e0 mm/slab_common.c:945 kmalloc_node include/linux/slab.h:589 [inline] bpf_map_kmalloc_node+0xd0/0x2c0 kernel/bpf/syscall.c:454 __dev_map_alloc_node+0x5c/0x4e0 kernel/bpf/devmap.c:851 __dev_map_update_elem kernel/bpf/devmap.c:916 [inline] dev_map_update_elem+0x20e/0x3f0 kernel/bpf/devmap.c:935 bpf_map_update_value+0x23a/0x410 kernel/bpf/syscall.c:228 map_update_elem+0x500/0x680 kernel/bpf/syscall.c:1443 __sys_bpf+0x460/0x7f0 kernel/bpf/syscall.c:4995 __do_sys_bpf kernel/bpf/syscall.c:5111 [inline] __se_sys_bpf kernel/bpf/syscall.c:5109 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5109 x64_sys_call+0x87f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:322 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 Freed by task 5829: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:516 ____kasan_slab_free+0x131/0x180 mm/kasan/common.c:241 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:249 kasan_slab_free include/linux/kasan.h:178 [inline] slab_free_hook mm/slub.c:1745 [inline] slab_free_freelist_hook mm/slub.c:1771 [inline] slab_free mm/slub.c:3686 [inline] __kmem_cache_free+0x21d/0x410 mm/slub.c:3702 kfree+0x7a/0xf0 mm/slab_common.c:990 dev_map_free+0x593/0x6c0 kernel/bpf/devmap.c:238 bpf_map_free_deferred+0xf7/0x1b0 kernel/bpf/syscall.c:637 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:295 The buggy address belongs to the object at ffff888119107900 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 0 bytes inside of 96-byte region [ffff888119107900, ffff888119107960) The buggy address belongs to the physical page: page:ffffea00046441c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x119107 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 ffffea0004c4f100 dead000000000005 ffff888100042900 raw: 0000000000000000 0000000000200020 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 0x112800(GFP_NOWAIT|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 20016, tgid 20015 (syz.9.6489), ts 974346257017, free_ts 974344478040 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x213/0x220 mm/page_alloc.c:2637 prep_new_page+0x1b/0x110 mm/page_alloc.c:2644 get_page_from_freelist+0x3a98/0x3b10 mm/page_alloc.c:4539 __alloc_pages+0x234/0x610 mm/page_alloc.c:5837 alloc_slab_page+0x6c/0xf0 include/linux/gfp.h:-1 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+0x207/0x2a0 mm/slub.c:3462 __do_kmalloc_node mm/slab_common.c:937 [inline] __kmalloc_node+0xa3/0x1e0 mm/slab_common.c:945 kmalloc_node include/linux/slab.h:589 [inline] __alloc kernel/bpf/memalloc.c:146 [inline] alloc_bulk+0x43b/0x790 kernel/bpf/memalloc.c:174 bpf_mem_refill+0xb3/0x590 kernel/bpf/memalloc.c:301 irq_work_single kernel/irq_work.c:212 [inline] irq_work_run_list+0x1d8/0x2f0 kernel/irq_work.c:243 irq_work_run+0x69/0xf0 kernel/irq_work.c:252 __sysvec_irq_work+0x63/0x1b0 arch/x86/kernel/irq_work.c:22 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0xa1/0xc0 arch/x86/kernel/irq_work.c:17 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1545 [inline] free_pcp_prepare mm/page_alloc.c:1619 [inline] free_unref_page_prepare+0x9f1/0xa00 mm/page_alloc.c:3581 free_unref_page+0xb2/0x5c0 mm/page_alloc.c:3677 free_the_page mm/page_alloc.c:830 [inline] __free_pages+0x61/0xf0 mm/page_alloc.c:5926 __vunmap+0x9c6/0xb80 mm/vmalloc.c:2729 __vfree mm/vmalloc.c:2778 [inline] vfree+0x5c/0x80 mm/vmalloc.c:2809 bpf_check+0x1189e/0x17ed0 kernel/bpf/verifier.c:15687 bpf_prog_load+0x1304/0x1bf0 kernel/bpf/syscall.c:2626 __sys_bpf+0x52c/0x7f0 kernel/bpf/syscall.c:5007 __do_sys_bpf kernel/bpf/syscall.c:5111 [inline] __se_sys_bpf kernel/bpf/syscall.c:5109 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5109 x64_sys_call+0x87f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:322 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: ffff888119107800: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff888119107880: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff888119107900: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff888119107980: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff888119107a00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ================================================================== general protection fault, probably for non-canonical address 0xdffffc0000000044: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000220-0x0000000000000227] CPU: 0 PID: 21904 Comm: syz.6.7176 Tainted: G B W 6.1.129-syzkaller-00055-gca24c52e3c25 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:__xdp_enqueue kernel/bpf/devmap.c:481 [inline] RIP: 0010:dev_map_enqueue+0x91/0x340 kernel/bpf/devmap.c:534 Code: d0 00 00 00 4c 89 e8 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 ef e8 5f a0 25 00 bb 20 02 00 00 49 03 5d 00 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 df e8 40 a0 25 00 48 83 3b 00 0f 84 eb RSP: 0018:ffffc90000a475f8 EFLAGS: 00010206 RAX: 0000000000000044 RBX: 0000000000000220 RCX: ffffffff8197a441 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88811236dad0 RBP: ffffc90000a47638 R08: ffffffff8144b443 R09: fffffbfff0f6e8fd R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: ffff88811236dad0 R14: ffff88811236da00 R15: ffff88812f307070 FS: 00007f85bf36d6c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d61bff8 CR3: 0000000124d97000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: __xdp_do_redirect_frame net/core/filter.c:4319 [inline] xdp_do_redirect_frame+0x2b5/0x800 net/core/filter.c:4381 xdp_test_run_batch net/bpf/test_run.c:314 [inline] bpf_test_run_xdp_live+0xc30/0x1f70 net/bpf/test_run.c:362 bpf_prog_test_run_xdp+0x7d1/0x1130 net/bpf/test_run.c:1393 bpf_prog_test_run+0x3b0/0x630 kernel/bpf/syscall.c:3670 __sys_bpf+0x59f/0x7f0 kernel/bpf/syscall.c:5025 __do_sys_bpf kernel/bpf/syscall.c:5111 [inline] __se_sys_bpf kernel/bpf/syscall.c:5109 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5109 x64_sys_call+0x87f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:322 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: 0033:0x7f85be58d169 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:00007f85bf36d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f85be7a5fa0 RCX: 00007f85be58d169 RDX: 0000000000000050 RSI: 00002000000000c0 RDI: 000000000000000a RBP: 00007f85be60e730 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f85be7a5fa0 R15: 00007ffcd2929618 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__xdp_enqueue kernel/bpf/devmap.c:481 [inline] RIP: 0010:dev_map_enqueue+0x91/0x340 kernel/bpf/devmap.c:534 Code: d0 00 00 00 4c 89 e8 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 ef e8 5f a0 25 00 bb 20 02 00 00 49 03 5d 00 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 df e8 40 a0 25 00 48 83 3b 00 0f 84 eb RSP: 0018:ffffc90000a475f8 EFLAGS: 00010206 RAX: 0000000000000044 RBX: 0000000000000220 RCX: ffffffff8197a441 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88811236dad0 RBP: ffffc90000a47638 R08: ffffffff8144b443 R09: fffffbfff0f6e8fd R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: ffff88811236dad0 R14: ffff88811236da00 R15: ffff88812f307070 FS: 00007f85bf36d6c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d61bff8 CR3: 0000000124d97000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 ---------------- Code disassembly (best guess): 0: d0 00 rolb (%rax) 2: 00 00 add %al,(%rax) 4: 4c 89 e8 mov %r13,%rax 7: 48 c1 e8 03 shr $0x3,%rax b: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) 10: 74 08 je 0x1a 12: 4c 89 ef mov %r13,%rdi 15: e8 5f a0 25 00 call 0x25a079 1a: bb 20 02 00 00 mov $0x220,%ebx 1f: 49 03 5d 00 add 0x0(%r13),%rbx 23: 48 89 d8 mov %rbx,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) <-- trapping instruction 2f: 74 08 je 0x39 31: 48 89 df mov %rbx,%rdi 34: e8 40 a0 25 00 call 0x25a079 39: 48 83 3b 00 cmpq $0x0,(%rbx) 3d: 0f .byte 0xf 3e: 84 eb test %ch,%bl