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: 29269 Comm: kworker/u5:0 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 : dfbfde48 ip : dfbfde78 fp : dfbfde74 r10: 827e4712 r9 : 89edd800 r8 : ffffffff r7 : 89eddb4c r6 : 00000001 r5 : 89edb000 r4 : 00000000 r3 : 00000000 r2 : 00000000 r1 : 89edb000 r0 : 89edd800 Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 8bc8f5c0 DAC: fffffffd Register r0 information: slab kmalloc-2k start 89edd800 pointer offset 0 size 2048 Register r1 information: slab kmalloc-2k start 89edb000 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 89edb000 pointer offset 0 size 2048 Register r6 information: non-paged memory Register r7 information: slab kmalloc-2k start 89edd800 pointer offset 844 size 2048 Register r8 information: non-paged memory Register r9 information: slab kmalloc-2k start 89edd800 pointer offset 0 size 2048 Register r10 information: non-slab/vmalloc memory Register r11 information: 2-page vmalloc region starting at 0xdfbfc000 allocated at kernel_clone+0xac/0x424 kernel/fork.c:2909 Register r12 information: 2-page vmalloc region starting at 0xdfbfc000 allocated at kernel_clone+0xac/0x424 kernel/fork.c:2909 Process kworker/u5:0 (pid: 29269, stack limit = 0xdfbfc000) Stack: (0xdfbfde48 to 0xdfbfe000) de40: 8a45e9c0 00000014 89edd800 89edd840 89eddb4c 82604d40 de60: 89eddbcc 827e4712 dfbfde9c dfbfde78 807c9ca0 807c96b8 00000000 736573e0 de80: 89eddbbc 89edd800 89edd840 89eddb4c dfbfdf04 dfbfdea0 81826728 807c9c64 dea0: dfbfdebc dfbfdeb0 00092626 89edd800 00000000 dfbfdec0 00000000 81825258 dec0: 00000000 00000000 dfbfdec8 dfbfdec8 89edd800 736573e0 dfbfdf48 89821300 dee0: 89eddbbc 82c21400 82c0f000 00000140 8a45e9c0 82c21405 dfbfdf44 dfbfdf08 df00: 80265fd4 8182638c dfbfdf2c dfbfdf18 dfbfdf44 dfbfdf20 8026196c 89821300 df20: 8982132c 82c0f000 82604d40 82c0f020 8a45e9c0 61c88647 dfbfdf84 dfbfdf48 df40: 80266520 80265e44 82604d40 82604d40 61c88647 8982132c dfbfdf84 8cc6c700 df60: 8a45e9c0 802662e0 89821300 8a571180 ea9d9e98 00000000 dfbfdfac dfbfdf88 df80: 8026d8e0 802662ec 8cc6c700 8026d7dc 00000000 00000000 00000000 00000000 dfa0: 00000000 dfbfdfb0 80200104 8026d7e8 00000000 00000000 00000000 00000000 dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 dfe0: 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 r9:89eddbcc r8:82604d40 r7:89eddb4c r6:89edd840 r5:89edd800 r4:00000014 r3:8a45e9c0 [<807c9c58>] (io_destroy_buffers) from [<81826728>] (io_ring_ctx_free io_uring/io_uring.c:2895 [inline]) [<807c9c58>] (io_destroy_buffers) from [<81826728>] (io_ring_exit_work+0x3a8/0x5ec io_uring/io_uring.c:3151) r7:89eddb4c r6:89edd840 r5:89edd800 r4:89eddbbc [<81826380>] (io_ring_exit_work) from [<80265fd4>] (process_one_work+0x19c/0x4a8 kernel/workqueue.c:2630) r10:82c21405 r9:8a45e9c0 r8:00000140 r7:82c0f000 r6:82c21400 r5:89eddbbc r4:89821300 [<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 r9:8a45e9c0 r8:82c0f020 r7:82604d40 r6:82c0f000 r5:8982132c r4:89821300 [<802662e0>] (worker_thread) from [<8026d8e0>] (kthread+0x104/0x134 kernel/kthread.c:388) r10:00000000 r9:ea9d9e98 r8:8a571180 r7:89821300 r6:802662e0 r5:8a45e9c0 r4:8cc6c700 [<8026d7dc>] (kthread) from [<80200104>] (ret_from_fork+0x14/0x30 arch/arm/kernel/entry-common.S:134) Exception stack(0xdfbfdfb0 to 0xdfbfdff8) dfa0: 00000000 00000000 00000000 00000000 dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:8026d7dc r4:8cc6c700 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