8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 00000000 when read [00000000] *pgd=83f6c003, *pmd=fe704003 Internal error: Oops: 205 [#1] PREEMPT SMP ARM Modules linked in: CPU: 0 PID: 16515 Comm: syz.1.3334 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 : [<804810d0>] lr : [<808067d4>] psr: 60000013 sp : dfb6dca0 ip : dfb6dcb0 fp : dfb6dcac r10: 00000018 r9 : 8285f4e8 r8 : 00000000 r7 : 00000000 r6 : 00000000 r5 : 00000000 r4 : 84586000 r3 : 00c00000 r2 : 0000071f r1 : 00000000 r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 84d2b600 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 84586000 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 0xdfb6c000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2797 Register r12 information: 2-page vmalloc region starting at 0xdfb6c000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2797 Process syz.1.3334 (pid: 16515, stack limit = 0xdfb6c000) Stack: (0xdfb6dca0 to 0xdfb6e000) dca0: dfb6dce4 dfb6dcb0 808067d4 804810d0 dfb6dcd4 dfb6df48 8024d29c 84586000 dcc0: 84586000 00000000 00000001 00000000 000000c7 00000018 dfb6dd34 dfb6dce8 dce0: 81461fc4 808066e8 00000000 9810de58 850e7a00 850e7ae0 85176400 850e7ae8 dd00: dfb6df48 00000002 dfb6dd8c 85176400 000000c7 850e7a00 83485400 00000000 dd20: 00000102 00000000 dfb6dda4 dfb6dd38 81689af0 81461ee0 00000102 00000000 dd40: 00000000 00000000 00000000 00000000 85176488 850e7afc 85176634 dfb6df38 dd60: 00000000 9810de58 818f6a18 821cb998 00000102 9810de58 dfb6df38 816899a0 dd80: dfb6df38 833a7180 00000102 00000000 00000102 dfb6ddf4 dfb6ddc4 dfb6dda8 dda0: 81688838 816899ac 00000000 00000102 00000000 81688800 dfb6dde4 dfb6ddc8 ddc0: 813d1084 8168880c dfb6df38 200004c0 833a7180 00000000 dfb6dea4 dfb6dde8 dde0: 813d1288 813d1040 00000001 00000000 dfb6de34 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 9810de58 00000000 00000000 de80: dfb6df38 200004c0 00000102 833a7180 83485400 00000129 dfb6df24 dfb6dea8 dea0: 813d436c 813d1204 00000102 00000000 802873d4 00000000 00000000 200002c0 dec0: 000000c7 00000000 00000000 00000000 00000000 00000000 00000000 00000000 dee0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 9810de58 df00: dfb6df24 833a7180 00000000 200004c0 00000102 8020029c dfb6dfa4 dfb6df28 df20: 813d4b4c 813d42f0 00000000 dfb6df38 00000001 fffffff7 dfb6ddf4 00000000 df40: 00000000 00000000 00000000 00000001 200002c0 000000c6 00000001 00000000 df60: 00000000 00000001 00000000 00000000 00000000 00000000 00000000 00000000 df80: 8020c910 9810de58 00000000 00000000 002642e0 00000129 00000000 dfb6dfa8 dfa0: 80200060 813d4ae4 00000000 00000000 00000003 200004c0 00000102 00000000 dfc0: 00000000 00000000 002642e0 00000129 7efe8776 7efe8777 003d0f00 76bb00bc dfe0: 76bafec8 76bafeb8 00017ecc 00130aa0 60000010 00000003 00000000 00000000 Call trace: [<804810c4>] (__kmap_local_page_prot) from [<808067d4>] (kmap_local_page include/linux/highmem-internal.h:73 [inline]) [<804810c4>] (__kmap_local_page_prot) from [<808067d4>] (copy_page_to_iter+0xf8/0x184 lib/iov_iter.c:360) [<808066dc>] (copy_page_to_iter) from [<81461fc4>] (sk_msg_recvmsg+0xf0/0x3cc net/core/skmsg.c:437) r10:00000018 r9:000000c7 r8:00000000 r7:00000001 r6:00000000 r5:84586000 r4:84586000 [<81461ed4>] (sk_msg_recvmsg) from [<81689af0>] (unix_bpf_recvmsg net/unix/unix_bpf.c:73 [inline]) [<81461ed4>] (sk_msg_recvmsg) from [<81689af0>] (unix_bpf_recvmsg+0x150/0x444 net/unix/unix_bpf.c:50) r10:00000000 r9:00000102 r8:00000000 r7:83485400 r6:850e7a00 r5:000000c7 r4:85176400 [<816899a0>] (unix_bpf_recvmsg) from [<81688838>] (unix_dgram_recvmsg+0x38/0x4c net/unix/af_unix.c:2488) r10:dfb6ddf4 r9:00000102 r8:00000000 r7:00000102 r6:833a7180 r5:dfb6df38 r4:816899a0 [<81688800>] (unix_dgram_recvmsg) from [<813d1084>] (sock_recvmsg_nosec net/socket.c:1046 [inline]) [<81688800>] (unix_dgram_recvmsg) from [<813d1084>] (sock_recvmsg+0x50/0x78 net/socket.c:1068) r4:81688800 [<813d1034>] (sock_recvmsg) from [<813d1288>] (____sys_recvmsg+0x90/0x184 net/socket.c:2804) r7:00000000 r6:833a7180 r5:200004c0 r4:dfb6df38 [<813d11f8>] (____sys_recvmsg) from [<813d436c>] (___sys_recvmsg+0x88/0xbc net/socket.c:2846) r10:00000129 r9:83485400 r8:833a7180 r7:00000102 r6:200004c0 r5:dfb6df38 r4:00000000 [<813d42e4>] (___sys_recvmsg) from [<813d4b4c>] (__sys_recvmsg net/socket.c:2876 [inline]) [<813d42e4>] (___sys_recvmsg) from [<813d4b4c>] (__do_sys_recvmsg net/socket.c:2886 [inline]) [<813d42e4>] (___sys_recvmsg) from [<813d4b4c>] (sys_recvmsg+0x74/0xb8 net/socket.c:2883) r8:8020029c r7:00000102 r6:200004c0 r5:00000000 r4:833a7180 [<813d4ad8>] (sys_recvmsg) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfb6dfa8 to 0xdfb6dff0) dfa0: 00000000 00000000 00000003 200004c0 00000102 00000000 dfc0: 00000000 00000000 002642e0 00000129 7efe8776 7efe8777 003d0f00 76bb00bc dfe0: 76bafec8 76bafeb8 00017ecc 00130aa0 r7:00000129 r6:002642e0 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