8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 00000000 when read [00000000] *pgd=84453003, *pmd=fe4f0003 Internal error: Oops: 205 [#1] PREEMPT SMP ARM Modules linked in: CPU: 0 PID: 4689 Comm: syz.0.223 Not tainted 6.10.0-rc7-syzkaller #0 Hardware name: ARM-Versatile Express PC is at page_zonenum include/linux/mmzone.h:1102 [inline] PC is at __kmap_local_page_prot+0xc/0x74 mm/highmem.c:573 LR is at kmap_local_page include/linux/highmem-internal.h:73 [inline] LR is at copy_page_to_iter+0xf8/0x184 lib/iov_iter.c:360 pc : [<804810b0>] lr : [<808067e4>] psr: 60000013 sp : df9f5ca0 ip : df9f5cb0 fp : df9f5cac r10: 00000018 r9 : 8285f4e8 r8 : 00000000 r7 : 00000000 r6 : 00000000 r5 : 00000000 r4 : 85312c00 r3 : 00c00000 r2 : 0000071f r1 : 00000000 r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 8506e940 DAC: fffffffd Register r0 information: NULL pointer Register r1 information: NULL pointer Register r2 information: non-paged memory Register r3 information: non-paged memory Register r4 information: slab kmalloc-1k start 85312c00 pointer offset 0 size 1024 Register r5 information: NULL pointer Register r6 information: NULL pointer Register r7 information: NULL pointer Register r8 information: NULL pointer Register r9 information: non-slab/vmalloc memory Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xdf9f4000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2797 Register r12 information: 2-page vmalloc region starting at 0xdf9f4000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2797 Process syz.0.223 (pid: 4689, stack limit = 0xdf9f4000) Stack: (0xdf9f5ca0 to 0xdf9f6000) 5ca0: df9f5ce4 df9f5cb0 808067e4 804810b0 df9f5cd4 df9f5f48 8024d2a4 85312c00 5cc0: 85312c00 00000000 00000001 00000000 000000c7 00000018 df9f5d34 df9f5ce8 5ce0: 814620fc 808066f8 00000000 60009b88 84f43800 84f438e0 83e9c300 84f438e8 5d00: df9f5f48 00000002 df9f5d8c 83e9c300 000000c7 84f43800 83713c00 00000000 5d20: 00000102 00000000 df9f5da4 df9f5d38 81689be8 81462018 00000102 00000000 5d40: 00000000 00000000 00000000 00000000 83e9c388 84f438fc 83e9c534 df9f5f38 5d60: 00000000 60009b88 8260ca7c 821cb998 00000102 60009b88 df9f5f38 81689a98 5d80: df9f5f38 831daf00 00000102 00000000 00000102 df9f5df4 df9f5dc4 df9f5da8 5da0: 81688980 81689aa4 00000000 00000102 00000000 81688948 df9f5de4 df9f5dc8 5dc0: 813d1104 81688954 df9f5f38 200004c0 831daf00 00000000 df9f5ea4 df9f5de8 5de0: 813d1308 813d10c0 00000001 00000000 df9f5e34 00000000 00000000 00000000 5e00: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 5e20: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 5e40: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 5e60: 00000000 00000000 00000000 00000000 00000000 60009b88 00000000 00000000 5e80: df9f5f38 200004c0 00000102 831daf00 83713c00 00000129 df9f5f24 df9f5ea8 5ea0: 813d43ec 813d1284 00000102 00000000 802873dc 00000000 00000000 200002c0 5ec0: 000000c7 00000000 00000000 00000000 00000000 00000000 00000000 00000000 5ee0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 60009b88 5f00: df9f5f24 831daf00 00000000 200004c0 00000102 8020029c df9f5fa4 df9f5f28 5f20: 813d4bcc 813d4370 00000000 df9f5f38 00000001 fffffff7 df9f5df4 00000000 5f40: 00000000 00000000 00000000 00000001 200002c0 000000c6 00000001 00000000 5f60: 00000000 00000001 00000000 00000000 00000000 00000000 00000000 00000000 5f80: 8020c910 60009b88 00000000 00000000 00264370 00000129 00000000 df9f5fa8 5fa0: 80200060 813d4b64 00000000 00000000 00000005 200004c0 00000102 00000000 5fc0: 00000000 00000000 00264370 00000129 7e9b6766 7e9b6767 003d0f00 76b0e0bc 5fe0: 76b0dec8 76b0deb8 00018394 001304f0 60000010 00000005 00000000 00000000 Call trace: [<804810a4>] (__kmap_local_page_prot) from [<808067e4>] (kmap_local_page include/linux/highmem-internal.h:73 [inline]) [<804810a4>] (__kmap_local_page_prot) from [<808067e4>] (copy_page_to_iter+0xf8/0x184 lib/iov_iter.c:360) [<808066ec>] (copy_page_to_iter) from [<814620fc>] (sk_msg_recvmsg+0xf0/0x3cc net/core/skmsg.c:437) r10:00000018 r9:000000c7 r8:00000000 r7:00000001 r6:00000000 r5:85312c00 r4:85312c00 [<8146200c>] (sk_msg_recvmsg) from [<81689be8>] (unix_bpf_recvmsg net/unix/unix_bpf.c:73 [inline]) [<8146200c>] (sk_msg_recvmsg) from [<81689be8>] (unix_bpf_recvmsg+0x150/0x444 net/unix/unix_bpf.c:50) r10:00000000 r9:00000102 r8:00000000 r7:83713c00 r6:84f43800 r5:000000c7 r4:83e9c300 [<81689a98>] (unix_bpf_recvmsg) from [<81688980>] (unix_dgram_recvmsg+0x38/0x4c net/unix/af_unix.c:2488) r10:df9f5df4 r9:00000102 r8:00000000 r7:00000102 r6:831daf00 r5:df9f5f38 r4:81689a98 [<81688948>] (unix_dgram_recvmsg) from [<813d1104>] (sock_recvmsg_nosec net/socket.c:1046 [inline]) [<81688948>] (unix_dgram_recvmsg) from [<813d1104>] (sock_recvmsg+0x50/0x78 net/socket.c:1068) r4:81688948 [<813d10b4>] (sock_recvmsg) from [<813d1308>] (____sys_recvmsg+0x90/0x184 net/socket.c:2804) r7:00000000 r6:831daf00 r5:200004c0 r4:df9f5f38 [<813d1278>] (____sys_recvmsg) from [<813d43ec>] (___sys_recvmsg+0x88/0xbc net/socket.c:2846) r10:00000129 r9:83713c00 r8:831daf00 r7:00000102 r6:200004c0 r5:df9f5f38 r4:00000000 [<813d4364>] (___sys_recvmsg) from [<813d4bcc>] (__sys_recvmsg net/socket.c:2876 [inline]) [<813d4364>] (___sys_recvmsg) from [<813d4bcc>] (__do_sys_recvmsg net/socket.c:2886 [inline]) [<813d4364>] (___sys_recvmsg) from [<813d4bcc>] (sys_recvmsg+0x74/0xb8 net/socket.c:2883) r8:8020029c r7:00000102 r6:200004c0 r5:00000000 r4:831daf00 [<813d4b58>] (sys_recvmsg) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf9f5fa8 to 0xdf9f5ff0) 5fa0: 00000000 00000000 00000005 200004c0 00000102 00000000 5fc0: 00000000 00000000 00264370 00000129 7e9b6766 7e9b6767 003d0f00 76b0e0bc 5fe0: 76b0dec8 76b0deb8 00018394 001304f0 r7:00000129 r6:00264370 r5:00000000 r4:00000000 Code: eaffffe8 e1a0c00d e92dd800 e24cb004 (e5901000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: eaffffe8 b 0xffffffa8 4: e1a0c00d mov ip, sp 8: e92dd800 push {fp, ip, lr, pc} c: e24cb004 sub fp, ip, #4 * 10: e5901000 ldr r1, [r0] <-- trapping instruction