8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 0000000e when read [0000000e] *pgd=844b2003, *pmd=df962003 Internal error: Oops: 205 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 4849 Comm: syz.1.284 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 : dfb75dc0 ip : dfb75e08 fp : dfb75e04 r10: 00000240 r9 : 00000000 r8 : 8557b7c0 r7 : 8558e90c r6 : 8558e900 r5 : dfb75e44 r4 : 853e9000 r3 : 00000001 r2 : 8558e90c r1 : dfb75e44 r0 : 853e9000 Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 855df840 DAC: fffffffd Register r0 information: slab io_kiocb start 853e9000 pointer offset 0 size 192 Register r1 information: 2-page vmalloc region starting at 0xdfb74000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2844 Register r2 information: slab kmalloc-256 start 8558e900 pointer offset 12 size 256 Register r3 information: non-paged memory Register r4 information: slab io_kiocb start 853e9000 pointer offset 0 size 192 Register r5 information: 2-page vmalloc region starting at 0xdfb74000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2844 Register r6 information: slab kmalloc-256 start 8558e900 pointer offset 0 size 256 Register r7 information: slab kmalloc-256 start 8558e900 pointer offset 12 size 256 Register r8 information: slab kmalloc-64 start 8557b7c0 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 0xdfb74000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2844 Register r12 information: 2-page vmalloc region starting at 0xdfb74000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2844 Process syz.1.284 (pid: 4849, stack limit = 0xdfb74000) Stack: (0xdfb75dc0 to 0xdfb76000) 5dc0: 81a4be34 8030cb0c 84992900 00000001 00010000 8558e90c 00000000 853e9000 5de0: dfb75e44 8558e900 8558e90c 00000000 80000001 00000240 dfb75e1c dfb75e08 5e00: 80889cb0 80889554 835d6a00 853e9000 dfb75e84 dfb75e20 808931e0 80889c54 5e20: dfb75e4c dfb75e30 8089ec2c 8050a4c4 00010001 00000001 8057abbc 00000000 5e40: 00000000 8558e90c 00000000 00000000 00010001 719ccab2 80886a40 853e9000 5e60: 81cf0ca0 00000000 80000001 81cf0b5c 0000001b 8330bc00 dfb75ebc dfb75e88 5e80: 80886bd8 80892f38 853e9240 853e9180 853e90c0 84992800 853e906c 853e9000 5ea0: 85660000 00000000 00000000 8330bc00 dfb75f14 dfb75ec0 808877a8 80886b7c 5ec0: 8088e164 81a4bdd8 dfb75f24 dfb75ed8 00000800 00000800 81cf0b5c 00000800 5ee0: 84992800 719ccab2 85514840 00000042 84992800 00003517 85514840 00000000 5f00: 8330bc00 00000000 dfb75fa4 dfb75f18 80888250 808875a8 ecac8b10 84992840 5f20: 00000000 0000173d 81a4fbb0 81a4fa80 dfb75f54 dfb75f40 8026b438 8029ce1c 5f40: dfb75fb0 40000000 dfb75f84 dfb75f58 802229dc 8026b3f4 00000000 8281d05c 5f60: dfb75fb0 0014c490 ecac8b10 80222930 00000000 719ccab2 dfb75fac 00000000 5f80: 00000000 002e630c 000001aa 8020029c 8330bc00 000001aa 00000000 dfb75fa8 5fa0: 80200060 80888124 00000000 00000000 00000006 00003517 0000173d 00000042 5fc0: 00000000 00000000 002e630c 000001aa 002d0000 00000000 00006364 76b290bc 5fe0: 76b28ec0 76b28eb0 0001939c 00131f30 60000010 00000006 00000000 00000000 Call trace: [<80889548>] (io_ring_buffers_peek) from [<80889cb0>] (io_buffers_peek+0x68/0x8c io_uring/kbuf.c:343) r10:00000240 r9:80000001 r8:00000000 r7:8558e90c r6:8558e900 r5:dfb75e44 r4:853e9000 [<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) r5:853e9000 r4:835d6a00 [<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) r10:8330bc00 r9:0000001b r8:81cf0b5c r7:80000001 r6:00000000 r5:81cf0ca0 r4:853e9000 [<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) r10:8330bc00 r9:00000000 r8:00000000 r7:85660000 r6:853e9000 r5:853e906c r4:84992800 [<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 r9:8330bc00 r8:00000000 r7:85514840 r6:00003517 r5:84992800 r4:00000042 [<80888118>] (sys_io_uring_enter) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfb75fa8 to 0xdfb75ff0) 5fa0: 00000000 00000000 00000006 00003517 0000173d 00000042 5fc0: 00000000 00000000 002e630c 000001aa 002d0000 00000000 00006364 76b290bc 5fe0: 76b28ec0 76b28eb0 0001939c 00131f30 r10:000001aa r9:8330bc00 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