8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 0000000e when read [0000000e] *pgd=856fc003, *pmd=df365003 Internal error: Oops: 205 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 4041 Comm: syz.1.66 Not tainted 6.15.0-rc5-syzkaller #0 PREEMPT Hardware name: ARM-Versatile Express PC is at io_ring_buffers_peek+0x24/0x258 io_uring/kbuf.c:227 LR is at io_buffers_peek+0x68/0x8c io_uring/kbuf.c:343 pc : [<8088956c>] lr : [<80889cb0>] psr: 20000013 sp : df9eddc0 ip : df9ede08 fp : df9ede04 r10: 00000242 r9 : 00000000 r8 : 84ffd980 r7 : 8568200c r6 : 85682000 r5 : df9ede44 r4 : 85727b40 r3 : 00000001 r2 : 8568200c r1 : df9ede44 r0 : 85727b40 Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 84fbb6c0 DAC: fffffffd Register r0 information: slab io_kiocb start 85727b40 pointer offset 0 size 192 Register r1 information: 2-page vmalloc region starting at 0xdf9ec000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2844 Register r2 information: slab kmalloc-256 start 85682000 pointer offset 12 size 256 Register r3 information: non-paged memory Register r4 information: slab io_kiocb start 85727b40 pointer offset 0 size 192 Register r5 information: 2-page vmalloc region starting at 0xdf9ec000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2844 Register r6 information: slab kmalloc-256 start 85682000 pointer offset 0 size 256 Register r7 information: slab kmalloc-256 start 85682000 pointer offset 12 size 256 Register r8 information: slab kmalloc-64 start 84ffd980 pointer offset 0 size 64 Register r9 information: NULL pointer Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xdf9ec000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2844 Register r12 information: 2-page vmalloc region starting at 0xdf9ec000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2844 Process syz.1.66 (pid: 4041, stack limit = 0xdf9ec000) Stack: (0xdf9eddc0 to 0xdf9ee000) ddc0: 81a4be54 8030cb0c 84cc3100 00000001 00010000 8568200c 00000000 85727b40 dde0: df9ede44 85682000 8568200c 00000000 80000001 00000242 df9ede1c df9ede08 de00: 80889cb0 80889554 8372f680 85727b40 df9ede84 df9ede20 808931e0 80889c54 de20: df9ede4c df9ede30 8089ec2c 8050a4c4 00010001 00000001 8057abbc 00000000 de40: 00000000 8568200c 00000000 00000000 00010001 390fb080 80886a40 85727b40 de60: 81cf0ca0 00000000 80000001 81cf0b5c 0000001b 84c90000 df9edebc df9ede88 de80: 80886bd8 80892f38 85727f00 85727a80 857279c0 84cc3000 85727bac 85727b40 dea0: 85580000 00000000 00000000 84c90000 df9edf14 df9edec0 808877a8 80886b7c dec0: 8088e164 81a4bdf8 df9edf24 df9eded8 00000800 00000800 81cf0b5c 00000800 dee0: 84cc3000 390fb080 847a6600 00000000 84cc3000 00003516 847a6600 00000000 df00: 84c90000 00000000 df9edfa4 df9edf18 80888250 808875a8 ecac8b10 84cc3040 df20: 00000000 00000000 81a4fbd0 81a4faa0 df9edf54 df9edf40 8026b438 8029ce1c df40: df9edfb0 40000000 df9edf84 df9edf58 802229dc 8026b3f4 00000000 8281d05c df60: df9edfb0 0014c490 ecac8b10 80222930 00000000 390fb080 df9edfac 00000000 df80: 00000000 002e630c 000001aa 8020029c 84c90000 000001aa 00000000 df9edfa8 dfa0: 80200060 80888124 00000000 00000000 00000004 00003516 00000000 00000000 dfc0: 00000000 00000000 002e630c 000001aa 002d0000 00000000 00006364 76b660bc dfe0: 76b65ec0 76b65eb0 0001939c 00131f30 60000010 00000004 00000000 00000000 Call trace: [<80889548>] (io_ring_buffers_peek) from [<80889cb0>] (io_buffers_peek+0x68/0x8c io_uring/kbuf.c:343) r10:00000242 r9:80000001 r8:00000000 r7:8568200c r6:85682000 r5:df9ede44 r4:85727b40 [<80889c48>] (io_buffers_peek) from [<808931e0>] (io_recv_buf_select io_uring/net.c:1077 [inline]) [<80889c48>] (io_buffers_peek) from [<808931e0>] (io_recv+0x2b4/0x46c io_uring/net.c:1138) r5:85727b40 r4:8372f680 [<80892f2c>] (io_recv) from [<80886bd8>] (__io_issue_sqe io_uring/io_uring.c:1740 [inline]) [<80892f2c>] (io_recv) from [<80886bd8>] (io_issue_sqe+0x68/0x658 io_uring/io_uring.c:1759) r10:84c90000 r9:0000001b r8:81cf0b5c r7:80000001 r6:00000000 r5:81cf0ca0 r4:85727b40 [<80886b70>] (io_issue_sqe) from [<808877a8>] (io_queue_sqe io_uring/io_uring.c:1975 [inline]) [<80886b70>] (io_issue_sqe) from [<808877a8>] (io_submit_sqe io_uring/io_uring.c:2231 [inline]) [<80886b70>] (io_issue_sqe) from [<808877a8>] (io_submit_sqes+0x20c/0x938 io_uring/io_uring.c:2348) r10:84c90000 r9:00000000 r8:00000000 r7:85580000 r6:85727b40 r5:85727bac r4:84cc3000 [<8088759c>] (io_submit_sqes) from [<80888250>] (__do_sys_io_uring_enter io_uring/io_uring.c:3408 [inline]) [<8088759c>] (io_submit_sqes) from [<80888250>] (sys_io_uring_enter+0x138/0x780 io_uring/io_uring.c:3342) r10:00000000 r9:84c90000 r8:00000000 r7:847a6600 r6:00003516 r5:84cc3000 r4:00000000 [<80888118>] (sys_io_uring_enter) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf9edfa8 to 0xdf9edff0) dfa0: 00000000 00000000 00000004 00003516 00000000 00000000 dfc0: 00000000 00000000 002e630c 000001aa 002d0000 00000000 00006364 76b660bc dfe0: 76b65ec0 76b65eb0 0001939c 00131f30 r10:000001aa r9:84c90000 r8:8020029c r7:000001aa r6:002e630c r5:00000000 r4:00000000 Code: e1a08002 e5912000 e50b2030 e1a05001 (e1d920be) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e1a08002 mov r8, r2 4: e5912000 ldr r2, [r1] 8: e50b2030 str r2, [fp, #-48] @ 0xffffffd0 c: e1a05001 mov r5, r1 * 10: e1d920be ldrh r2, [r9, #14] <-- trapping instruction