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: 1 PID: 25 Comm: kworker/u6:0 Not tainted 6.6.0-rc3-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 : [<807c967c>] lr : [<807c9c38>] psr: 20000013 sp : df881e48 ip : df881e78 fp : df881e74 r10: 827e4691 r9 : 8a39d000 r8 : ffffffff r7 : 8a39d34c r6 : 00000001 r5 : 8a398000 r4 : 00000000 r3 : 00000000 r2 : 00000000 r1 : 8a398000 r0 : 8a39d000 Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 846fbd00 DAC: 00000000 Register r0 information: slab kmalloc-2k start 8a39d000 pointer offset 0 size 2048 Register r1 information: slab kmalloc-2k start 8a398000 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 8a398000 pointer offset 0 size 2048 Register r6 information: non-paged memory Register r7 information: slab kmalloc-2k start 8a39d000 pointer offset 844 size 2048 Register r8 information: non-paged memory Register r9 information: slab kmalloc-2k start 8a39d000 pointer offset 0 size 2048 Register r10 information: non-slab/vmalloc memory Register r11 information: 2-page vmalloc region starting at 0xdf880000 allocated at kernel_clone+0xac/0x424 kernel/fork.c:2909 Register r12 information: 2-page vmalloc region starting at 0xdf880000 allocated at kernel_clone+0xac/0x424 kernel/fork.c:2909 Process kworker/u6:0 (pid: 25, stack limit = 0xdf880000) Stack: (0xdf881e48 to 0xdf882000) 1e40: 82e20000 00000014 8a39d000 8a39d040 8a39d34c 82604d40 1e60: 8a39d3cc 827e4691 df881e9c df881e78 807c9c38 807c9650 00000000 d8e1c134 1e80: 8a39d3bc 8a39d000 8a39d040 8a39d34c df881f04 df881ea0 818264f0 807c9bfc 1ea0: df881ebc df881eb0 00023ace 8a39d000 00000000 df881ec0 00000000 81825020 1ec0: 00000000 00000000 df881ec8 df881ec8 8a39d000 d8e1c134 df881f48 82c0bd00 1ee0: 8a39d3bc 82c21600 82c0f200 00000180 82e20000 82c21605 df881f44 df881f08 1f00: 80265fd4 81826154 df881f2c df881f18 df881f44 df881f20 8026196c 82c0bd00 1f20: 82c0bd2c 82c0f200 82604d40 82c0f220 82e20000 61c88647 df881f84 df881f48 1f40: 80266520 80265e44 82604d40 82604d40 61c88647 82c0bd2c df881f84 82cc6f80 1f60: 82e20000 802662e0 82c0bd00 82ce7080 df819e28 00000000 df881fac df881f88 1f80: 8026d8e0 802662ec 82cc6f80 8026d7dc 00000000 00000000 00000000 00000000 1fa0: 00000000 df881fb0 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: [<807c9644>] (__io_remove_buffers) from [<807c9c38>] (io_destroy_buffers+0x48/0x138 io_uring/kbuf.c:264) r10:827e4691 r9:8a39d3cc r8:82604d40 r7:8a39d34c r6:8a39d040 r5:8a39d000 r4:00000014 r3:82e20000 [<807c9bf0>] (io_destroy_buffers) from [<818264f0>] (io_ring_ctx_free io_uring/io_uring.c:2895 [inline]) [<807c9bf0>] (io_destroy_buffers) from [<818264f0>] (io_ring_exit_work+0x3a8/0x5ec io_uring/io_uring.c:3151) r7:8a39d34c r6:8a39d040 r5:8a39d000 r4:8a39d3bc [<81826148>] (io_ring_exit_work) from [<80265fd4>] (process_one_work+0x19c/0x4a8 kernel/workqueue.c:2630) r10:82c21605 r9:82e20000 r8:00000180 r7:82c0f200 r6:82c21600 r5:8a39d3bc r4:82c0bd00 [<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 r9:82e20000 r8:82c0f220 r7:82604d40 r6:82c0f200 r5:82c0bd2c r4:82c0bd00 [<802662e0>] (worker_thread) from [<8026d8e0>] (kthread+0x104/0x134 kernel/kthread.c:388) r10:00000000 r9:df819e28 r8:82ce7080 r7:82c0bd00 r6:802662e0 r5:82e20000 r4:82cc6f80 [<8026d7dc>] (kthread) from [<80200104>] (ret_from_fork+0x14/0x30 arch/arm/kernel/entry-common.S:134) Exception stack(0xdf881fb0 to 0xdf881ff8) 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 r4:82cc6f80 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