8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 00000000 when read [00000000] *pgd=84e9b003, *pmd=f3400003 Internal error: Oops: 205 [#1] PREEMPT SMP ARM Modules linked in: CPU: 1 PID: 9393 Comm: syz.0.999 Not tainted 6.10.0-rc6-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 : dfb5dca0 ip : dfb5dcb0 fp : dfb5dcac r10: 00000018 r9 : 8285f4e8 r8 : 00000000 r7 : 00000000 r6 : 00000000 r5 : 00000000 r4 : 84754000 r3 : 00c00000 r2 : 0000071f r1 : 00000000 r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85072300 DAC: 00000000 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 84754000 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 0xdfb5c000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2797 Register r12 information: 2-page vmalloc region starting at 0xdfb5c000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2797 Process syz.0.999 (pid: 9393, stack limit = 0xdfb5c000) Stack: (0xdfb5dca0 to 0xdfb5e000) dca0: dfb5dce4 dfb5dcb0 808067e4 804810b0 dfb5dcd4 dfb5df48 8024d2a4 84754000 dcc0: 84754000 00000000 00000000 00000000 000000b3 00000018 dfb5dd34 dfb5dce8 dce0: 814620d4 808066f8 40000013 8486d1c0 8b098800 8b0988e0 847a5500 8b0988e8 dd00: dfb5df48 00000000 dfb5dd34 847a5500 000000b3 8b098800 84cd6000 00000001 dd20: 00000000 00000000 dfb5dda4 dfb5dd38 81689bc0 81461ff0 00000000 00000000 dd40: 00000000 8b0988e0 8b0988d0 7fffffff 847a5588 8b0988fc 847a5734 dfb5df38 dd60: 00000000 84cd6000 802a492c 00000100 00000122 bd55dafe dfb5df38 81689a70 dd80: dfb5df38 8486d180 00000000 00000000 00000000 dfb5ddf4 dfb5ddc4 dfb5dda8 dda0: 81688958 81689a7c 00000000 00000000 00000000 81688920 dfb5dde4 dfb5ddc8 ddc0: 813d10dc 8168892c dfb5df38 200004c0 8486d180 00000000 dfb5dea4 dfb5dde8 dde0: 813d12e0 813d1098 00000001 00000000 dfb5de34 00000000 00000000 00000000 de00: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 de20: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 de40: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 de60: 00000000 00000000 00000000 00000000 00000000 bd55dafe 00000000 00000000 de80: dfb5df38 200004c0 00000000 8486d180 84cd6000 00000129 dfb5df24 dfb5dea8 dea0: 813d43c4 813d125c 00000000 00000000 802873dc 00000000 00000000 200006c0 dec0: 000000b3 00000000 00000000 00000000 00000000 00000000 00000000 00000000 dee0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 bd55dafe df00: dfb5df24 8486d180 00000000 200004c0 00000000 8020029c dfb5dfa4 dfb5df28 df20: 813d4ba4 813d4348 00000000 dfb5df38 00000001 fffffff7 dfb5ddf4 00000000 df40: 00000000 00000000 00000000 00000000 200006c0 000000b3 00000001 00000000 df60: 00000000 00000001 00000000 00000000 00000000 00000000 00000000 00000000 df80: 8020c910 bd55dafe 00000000 00000000 002542e0 00000129 00000000 dfb5dfa8 dfa0: 80200060 813d4b3c 00000000 00000000 00000003 200004c0 00000000 00000000 dfc0: 00000000 00000000 002542e0 00000129 7eba5776 7eba5777 003d0f00 76bb10bc dfe0: 76bb0ec8 76bb0eb8 00018374 00130460 60000010 00000003 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 [<814620d4>] (sk_msg_recvmsg+0xf0/0x3cc net/core/skmsg.c:437) r10:00000018 r9:000000b3 r8:00000000 r7:00000000 r6:00000000 r5:84754000 r4:84754000 [<81461fe4>] (sk_msg_recvmsg) from [<81689bc0>] (unix_bpf_recvmsg net/unix/unix_bpf.c:73 [inline]) [<81461fe4>] (sk_msg_recvmsg) from [<81689bc0>] (unix_bpf_recvmsg+0x150/0x444 net/unix/unix_bpf.c:50) r10:00000000 r9:00000000 r8:00000001 r7:84cd6000 r6:8b098800 r5:000000b3 r4:847a5500 [<81689a70>] (unix_bpf_recvmsg) from [<81688958>] (unix_dgram_recvmsg+0x38/0x4c net/unix/af_unix.c:2488) r10:dfb5ddf4 r9:00000000 r8:00000000 r7:00000000 r6:8486d180 r5:dfb5df38 r4:81689a70 [<81688920>] (unix_dgram_recvmsg) from [<813d10dc>] (sock_recvmsg_nosec net/socket.c:1046 [inline]) [<81688920>] (unix_dgram_recvmsg) from [<813d10dc>] (sock_recvmsg+0x50/0x78 net/socket.c:1068) r4:81688920 [<813d108c>] (sock_recvmsg) from [<813d12e0>] (____sys_recvmsg+0x90/0x184 net/socket.c:2804) r7:00000000 r6:8486d180 r5:200004c0 r4:dfb5df38 [<813d1250>] (____sys_recvmsg) from [<813d43c4>] (___sys_recvmsg+0x88/0xbc net/socket.c:2846) r10:00000129 r9:84cd6000 r8:8486d180 r7:00000000 r6:200004c0 r5:dfb5df38 r4:00000000 [<813d433c>] (___sys_recvmsg) from [<813d4ba4>] (__sys_recvmsg net/socket.c:2876 [inline]) [<813d433c>] (___sys_recvmsg) from [<813d4ba4>] (__do_sys_recvmsg net/socket.c:2886 [inline]) [<813d433c>] (___sys_recvmsg) from [<813d4ba4>] (sys_recvmsg+0x74/0xb8 net/socket.c:2883) r8:8020029c r7:00000000 r6:200004c0 r5:00000000 r4:8486d180 [<813d4b30>] (sys_recvmsg) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfb5dfa8 to 0xdfb5dff0) dfa0: 00000000 00000000 00000003 200004c0 00000000 00000000 dfc0: 00000000 00000000 002542e0 00000129 7eba5776 7eba5777 003d0f00 76bb10bc dfe0: 76bb0ec8 76bb0eb8 00018374 00130460 r7:00000129 r6:002542e0 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