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: 10415 Comm: kworker/u5:0 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 : [<807c9634>] lr : [<807c9bf0>] psr: 20000113 sp : e0499e48 ip : e0499e78 fp : e0499e74 r10: 827e4691 r9 : 8ca29000 r8 : ffffffff r7 : 8ca2934c r6 : 00000001 r5 : 8ca2a800 r4 : 00000000 r3 : 00000000 r2 : 00000000 r1 : 8ca2a800 r0 : 8ca29000 Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 84461700 DAC: fffffffd Register r0 information: slab kmalloc-2k start 8ca29000 pointer offset 0 size 2048 Register r1 information: slab kmalloc-2k start 8ca2a800 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 8ca2a800 pointer offset 0 size 2048 Register r6 information: non-paged memory Register r7 information: slab kmalloc-2k start 8ca29000 pointer offset 844 size 2048 Register r8 information: non-paged memory Register r9 information: slab kmalloc-2k start 8ca29000 pointer offset 0 size 2048 Register r10 information: non-slab/vmalloc memory Register r11 information: 2-page vmalloc region starting at 0xe0498000 allocated at kernel_clone+0xac/0x424 kernel/fork.c:2909 Register r12 information: 2-page vmalloc region starting at 0xe0498000 allocated at kernel_clone+0xac/0x424 kernel/fork.c:2909 Process kworker/u5:0 (pid: 10415, stack limit = 0xe0498000) Stack: (0xe0499e48 to 0xe049a000) 9e40: 8365d240 00000014 8ca29000 8ca29040 8ca2934c 82604d40 9e60: 8ca293cc 827e4691 e0499e9c e0499e78 807c9bf0 807c9608 00000000 15d45904 9e80: 8ca293bc 8ca29000 8ca29040 8ca2934c e0499f04 e0499ea0 81826490 807c9bb4 9ea0: e0499ebc e0499eb0 0003ac36 8ca29000 00000000 e0499ec0 00000000 81824fc0 9ec0: 00000000 00000000 e0499ec8 e0499ec8 8ca29000 15d45904 e0499f48 8a47ad00 9ee0: 8ca293bc 82c21400 82c0f000 00000140 8365d240 82c21405 e0499f44 e0499f08 9f00: 80265fd4 818260f4 e0499f2c e0499f18 e0499f44 e0499f20 8026196c 8a47ad00 9f20: 8a47ad2c 82c0f000 82604d40 82c0f020 8365d240 61c88647 e0499f84 e0499f48 9f40: 80266520 80265e44 e0499f64 e0499f58 81847b70 80278e68 e0499f84 8b00e980 9f60: 8365d240 802662e0 8a47ad00 8b00ec80 df88de98 00000000 e0499fac e0499f88 9f80: 8026d8e0 802662ec 8b00e980 8026d7dc 00000000 00000000 00000000 00000000 9fa0: 00000000 e0499fb0 80200104 8026d7e8 00000000 00000000 00000000 00000000 9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 9fe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000 Backtrace: [<807c95fc>] (__io_remove_buffers) from [<807c9bf0>] (io_destroy_buffers+0x48/0x138 io_uring/kbuf.c:264) r10:827e4691 r9:8ca293cc r8:82604d40 r7:8ca2934c r6:8ca29040 r5:8ca29000 r4:00000014 r3:8365d240 [<807c9ba8>] (io_destroy_buffers) from [<81826490>] (io_ring_ctx_free io_uring/io_uring.c:2895 [inline]) [<807c9ba8>] (io_destroy_buffers) from [<81826490>] (io_ring_exit_work+0x3a8/0x5ec io_uring/io_uring.c:3151) r7:8ca2934c r6:8ca29040 r5:8ca29000 r4:8ca293bc [<818260e8>] (io_ring_exit_work) from [<80265fd4>] (process_one_work+0x19c/0x4a8 kernel/workqueue.c:2630) r10:82c21405 r9:8365d240 r8:00000140 r7:82c0f000 r6:82c21400 r5:8ca293bc r4:8a47ad00 [<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 r9:8365d240 r8:82c0f020 r7:82604d40 r6:82c0f000 r5:8a47ad2c r4:8a47ad00 [<802662e0>] (worker_thread) from [<8026d8e0>] (kthread+0x104/0x134 kernel/kthread.c:388) r10:00000000 r9:df88de98 r8:8b00ec80 r7:8a47ad00 r6:802662e0 r5:8365d240 r4:8b00e980 [<8026d7dc>] (kthread) from [<80200104>] (ret_from_fork+0x14/0x30 arch/arm/kernel/entry-common.S:134) Exception stack(0xe0499fb0 to 0xe0499ff8) 9fa0: 00000000 00000000 00000000 00000000 9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 9fe0: 00000000 00000000 00000000 00000000 00000013 00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:8026d7dc r4:8b00e980 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