8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 0000000e when read [0000000e] *pgd=80000080004003, *pmd=00000000 Internal error: Oops: 207 [#1] PREEMPT SMP ARM Modules linked in: CPU: 0 PID: 4735 Comm: kworker/u5:13 Not tainted 6.6.0-rc4-syzkaller #0 Hardware name: ARM-Versatile Express Workqueue: events_unbound io_ring_exit_work PC is at __io_remove_buffers io_uring/kbuf.c:219 [inline] PC is at __io_remove_buffers+0x38/0x184 io_uring/kbuf.c:209 LR is at io_destroy_buffers+0x48/0x138 io_uring/kbuf.c:264 pc : [<807c96e4>] lr : [<807c9ca0>] psr: 20000113 sp : dfb51e48 ip : dfb51e78 fp : dfb51e74 r10: 827e4712 r9 : 8bc02000 r8 : ffffffff r7 : 8bc0234c r6 : 00000001 r5 : 8bc07000 r4 : 00000000 r3 : 00000000 r2 : 00000000 r1 : 8bc07000 r0 : 8bc02000 Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 89e7b400 DAC: fffffffd Register r0 information: slab kmalloc-2k start 8bc02000 pointer offset 0 size 2048 Register r1 information: slab kmalloc-2k start 8bc07000 pointer offset 0 size 2048 Register r2 information: NULL pointer Register r3 information: NULL pointer Register r4 information: NULL pointer Register r5 information: slab kmalloc-2k start 8bc07000 pointer offset 0 size 2048 Register r6 information: non-paged memory Register r7 information: slab kmalloc-2k start 8bc02000 pointer offset 844 size 2048 Register r8 information: non-paged memory Register r9 information: slab kmalloc-2k start 8bc02000 pointer offset 0 size 2048 Register r10 information: non-slab/vmalloc memory Register r11 information: 2-page vmalloc region starting at 0xdfb50000 allocated at kernel_clone+0xac/0x424 kernel/fork.c:2909 Register r12 information: 2-page vmalloc region starting at 0xdfb50000 allocated at kernel_clone+0xac/0x424 kernel/fork.c:2909 Process kworker/u5:13 (pid: 4735, stack limit = 0xdfb50000) Stack: (0xdfb51e48 to 0xdfb52000) 1e40: 84459780 00000014 8bc02000 8bc02040 8bc0234c 82604d40 1e60: 8bc023cc 827e4712 dfb51e9c dfb51e78 807c9ca0 807c96b8 00000000 56c7863f 1e80: 8bc023bc 8bc02000 8bc02040 8bc0234c dfb51f04 dfb51ea0 81826748 807c9c64 1ea0: dfb51ebc dfb51eb0 00037c7f 8bc02000 00000000 dfb51ec0 00000000 81825278 1ec0: 00000000 00000000 dfb51ec8 dfb51ec8 8bc02000 56c7863f dfb51f48 89d83c80 1ee0: 8bc023bc 82c21400 82c0f000 00000140 84459780 82c21405 dfb51f44 dfb51f08 1f00: 80265fd4 818263ac dfb51f2c dfb51f18 dfb51f44 dfb51f20 8026196c 89d83c80 1f20: 89d83cac 82c0f000 82604d40 82c0f020 84459780 61c88647 dfb51f84 dfb51f48 1f40: 80266520 80265e44 82604d40 82604d40 61c88647 89d83cac dfb51f84 89e61640 1f60: 84459780 802662e0 89d83c80 89e61b00 eaa3de98 00000000 dfb51fac dfb51f88 1f80: 8026d8e0 802662ec 89e61640 8026d7dc 00000000 00000000 00000000 00000000 1fa0: 00000000 dfb51fb0 80200104 8026d7e8 00000000 00000000 00000000 00000000 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000 Backtrace: [<807c96ac>] (__io_remove_buffers) from [<807c9ca0>] (io_destroy_buffers+0x48/0x138 io_uring/kbuf.c:264) r10:827e4712 r9:8bc023cc r8:82604d40 r7:8bc0234c r6:8bc02040 r5:8bc02000 r4:00000014 r3:84459780 [<807c9c58>] (io_destroy_buffers) from [<81826748>] (io_ring_ctx_free io_uring/io_uring.c:2895 [inline]) [<807c9c58>] (io_destroy_buffers) from [<81826748>] (io_ring_exit_work+0x3a8/0x5ec io_uring/io_uring.c:3151) r7:8bc0234c r6:8bc02040 r5:8bc02000 r4:8bc023bc [<818263a0>] (io_ring_exit_work) from [<80265fd4>] (process_one_work+0x19c/0x4a8 kernel/workqueue.c:2630) r10:82c21405 r9:84459780 r8:00000140 r7:82c0f000 r6:82c21400 r5:8bc023bc r4:89d83c80 [<80265e38>] (process_one_work) from [<80266520>] (process_scheduled_works kernel/workqueue.c:2703 [inline]) [<80265e38>] (process_one_work) from [<80266520>] (worker_thread+0x240/0x48c kernel/workqueue.c:2784) r10:61c88647 r9:84459780 r8:82c0f020 r7:82604d40 r6:82c0f000 r5:89d83cac r4:89d83c80 [<802662e0>] (worker_thread) from [<8026d8e0>] (kthread+0x104/0x134 kernel/kthread.c:388) r10:00000000 r9:eaa3de98 r8:89e61b00 r7:89d83c80 r6:802662e0 r5:84459780 r4:89e61640 [<8026d7dc>] (kthread) from [<80200104>] (ret_from_fork+0x14/0x30 arch/arm/kernel/entry-common.S:134) Exception stack(0xdfb51fb0 to 0xdfb51ff8) 1fa0: 00000000 00000000 00000000 00000000 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:8026d7dc r4:89e61640 Code: 0a000022 e5913004 e1d120be e5d14013 (e1d380be) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: 0a000022 beq 0x90 4: e5913004 ldr r3, [r1, #4] 8: e1d120be ldrh r2, [r1, #14] c: e5d14013 ldrb r4, [r1, #19] * 10: e1d380be ldrh r8, [r3, #14] <-- trapping instruction