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: 21342 Comm: kworker/u5:7 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 : ea941e48 ip : ea941e78 fp : ea941e74 r10: 827e4712 r9 : 846ff000 r8 : ffffffff r7 : 846ff34c r6 : 00000001 r5 : 846f9000 r4 : 00000000 r3 : 00000000 r2 : 00000000 r1 : 846f9000 r0 : 846ff000 Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 8482f540 DAC: fffffffd Register r0 information: slab kmalloc-2k start 846ff000 pointer offset 0 size 2048 Register r1 information: slab kmalloc-2k start 846f9000 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 846f9000 pointer offset 0 size 2048 Register r6 information: non-paged memory Register r7 information: slab kmalloc-2k start 846ff000 pointer offset 844 size 2048 Register r8 information: non-paged memory Register r9 information: slab kmalloc-2k start 846ff000 pointer offset 0 size 2048 Register r10 information: non-slab/vmalloc memory Register r11 information: 2-page vmalloc region starting at 0xea940000 allocated at kernel_clone+0xac/0x424 kernel/fork.c:2909 Register r12 information: 2-page vmalloc region starting at 0xea940000 allocated at kernel_clone+0xac/0x424 kernel/fork.c:2909 Process kworker/u5:7 (pid: 21342, stack limit = 0xea940000) Stack: (0xea941e48 to 0xea942000) 1e40: 82fa8000 00000014 846ff000 846ff040 846ff34c 82604d40 1e60: 846ff3cc 827e4712 ea941e9c ea941e78 807c9ca0 807c96b8 00000000 d52089cd 1e80: 846ff3bc 846ff000 846ff040 846ff34c ea941f04 ea941ea0 81826728 807c9c64 1ea0: ea941ebc ea941eb0 000273b5 846ff000 00000000 ea941ec0 00000000 81825258 1ec0: 00000000 00000000 ea941ec8 ea941ec8 846ff000 d52089cd ea941f48 88e3f280 1ee0: 846ff3bc 82c21400 82c0f000 00000140 82fa8000 82c21405 ea941f44 ea941f08 1f00: 80265fd4 8182638c ea941f2c ea941f18 ea941f44 ea941f20 8026196c 88e3f280 1f20: 88e3f2ac 82c0f000 82604d40 82c0f020 82fa8000 61c88647 ea941f84 ea941f48 1f40: 80266520 80265e44 82604d40 82604d40 61c88647 88e3f2ac ea941f84 88e58a00 1f60: 82fa8000 802662e0 88e3f280 88dbff00 ea939e98 00000000 ea941fac ea941f88 1f80: 8026d8e0 802662ec 88e58a00 8026d7dc 00000000 00000000 00000000 00000000 1fa0: 00000000 ea941fb0 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 r9:846ff3cc r8:82604d40 r7:846ff34c r6:846ff040 r5:846ff000 r4:00000014 r3:82fa8000 [<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) r7:846ff34c r6:846ff040 r5:846ff000 r4:846ff3bc [<81826380>] (io_ring_exit_work) from [<80265fd4>] (process_one_work+0x19c/0x4a8 kernel/workqueue.c:2630) r10:82c21405 r9:82fa8000 r8:00000140 r7:82c0f000 r6:82c21400 r5:846ff3bc r4:88e3f280 [<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 r9:82fa8000 r8:82c0f020 r7:82604d40 r6:82c0f000 r5:88e3f2ac r4:88e3f280 [<802662e0>] (worker_thread) from [<8026d8e0>] (kthread+0x104/0x134 kernel/kthread.c:388) r10:00000000 r9:ea939e98 r8:88dbff00 r7:88e3f280 r6:802662e0 r5:82fa8000 r4:88e58a00 [<8026d7dc>] (kthread) from [<80200104>] (ret_from_fork+0x14/0x30 arch/arm/kernel/entry-common.S:134) Exception stack(0xea941fb0 to 0xea941ff8) 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 r4:88e58a00 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