8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 00000000 when read [00000000] *pgd=86ac4003, *pmd=fee42003 Internal error: Oops: 207 [#1] PREEMPT SMP ARM Modules linked in: CPU: 0 PID: 18255 Comm: syz-executor.1 Not tainted 6.8.0-syzkaller #0 Hardware name: ARM-Versatile Express PC is at page_zonenum include/linux/mmzone.h:1100 [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 : [<80479af4>] lr : [<807ead94>] psr: 60000013 sp : dfcd5ca0 ip : dfcd5cb0 fp : dfcd5cac r10: 00000018 r9 : 828584e8 r8 : 00000000 r7 : 00000000 r6 : 00000000 r5 : 00000000 r4 : 84759800 r3 : 00c00000 r2 : 0000071f r1 : 00000000 r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 83e33e80 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 84759800 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 0xdfcd4000 allocated at kernel_clone+0xac/0x3cc kernel/fork.c:2796 Register r12 information: 2-page vmalloc region starting at 0xdfcd4000 allocated at kernel_clone+0xac/0x3cc kernel/fork.c:2796 Process syz-executor.1 (pid: 18255, stack limit = 0xdfcd4000) Stack: (0xdfcd5ca0 to 0xdfcd6000) 5ca0: dfcd5ce4 dfcd5cb0 807ead94 80479af4 dfcd5cd4 dfcd5f48 8024c840 84759800 5cc0: 84759800 00000000 00000001 00000000 000000c7 00000018 dfcd5d34 dfcd5ce8 5ce0: 8140ac24 807eaca8 00000000 b977087e 845a2e00 845a2ed0 82e14000 845a2ed8 5d00: dfcd5f48 00000002 dfcd5d8c 82e14000 000000c7 845a2e00 84756c00 00000000 5d20: 00000102 00000000 dfcd5da4 dfcd5d38 8162d318 8140ab40 00000102 00000000 5d40: 00000000 00000000 00000000 00000000 82e14088 845a2eec 82e14234 dfcd5f38 5d60: 00000000 b977087e 8189a6a8 8219a848 00000102 b977087e dfcd5f38 8162d1c8 5d80: dfcd5f38 831e2780 00000102 00000000 00000102 dfcd5df4 dfcd5dc4 dfcd5da8 5da0: 8162c3b4 8162d1d4 00000000 00000102 00000000 8162c37c dfcd5de4 dfcd5dc8 5dc0: 8137a210 8162c388 dfcd5f38 831e2780 200004c0 00000000 dfcd5ea4 dfcd5de8 5de0: 8137a410 8137a1cc 00000000 00000000 00000001 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 b977087e 00000000 00000000 5e80: dfcd5f38 200004c0 00000102 831e2780 84756c00 00000129 dfcd5f24 dfcd5ea8 5ea0: 8137d354 8137a38c 00000102 00000000 00000008 00000000 00000000 200002c0 5ec0: 000000c7 00000000 00000000 00000000 00000000 00000000 00000000 00000000 5ee0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 b977087e 5f00: dfcd5f24 831e2780 00000000 200004c0 00000102 80200288 dfcd5fa4 dfcd5f28 5f20: 8137dad0 8137d2d8 00000000 dfcd5f38 00000001 fffffff7 dfcd5df4 00000000 5f40: 00000000 00000000 00000000 00000001 200002c0 000000c6 00000001 00000000 5f60: 00000000 00000001 00000000 00000000 00000000 00000000 00000000 00000000 5f80: 8020ca6c b977087e 00000000 00000000 0014c2c8 00000129 00000000 dfcd5fa8 5fa0: 80200060 8137da68 00000000 00000000 00000003 200004c0 00000102 00000000 5fc0: 00000000 00000000 0014c2c8 00000129 7ed0432e 7ed0432f 003d0f00 76bea0fc 5fe0: 76be9f08 76be9ef8 000167f8 00050bc0 60000010 00000003 00000000 00000000 Backtrace: [<80479ae8>] (__kmap_local_page_prot) from [<807ead94>] (kmap_local_page include/linux/highmem-internal.h:73 [inline]) [<80479ae8>] (__kmap_local_page_prot) from [<807ead94>] (copy_page_to_iter+0xf8/0x184 lib/iov_iter.c:360) [<807eac9c>] (copy_page_to_iter) from [<8140ac24>] (sk_msg_recvmsg+0xf0/0x3cc net/core/skmsg.c:437) r10:00000018 r9:000000c7 r8:00000000 r7:00000001 r6:00000000 r5:84759800 r4:84759800 [<8140ab34>] (sk_msg_recvmsg) from [<8162d318>] (unix_bpf_recvmsg net/unix/unix_bpf.c:73 [inline]) [<8140ab34>] (sk_msg_recvmsg) from [<8162d318>] (unix_bpf_recvmsg+0x150/0x444 net/unix/unix_bpf.c:50) r10:00000000 r9:00000102 r8:00000000 r7:84756c00 r6:845a2e00 r5:000000c7 r4:82e14000 [<8162d1c8>] (unix_bpf_recvmsg) from [<8162c3b4>] (unix_dgram_recvmsg+0x38/0x4c net/unix/af_unix.c:2529) r10:dfcd5df4 r9:00000102 r8:00000000 r7:00000102 r6:831e2780 r5:dfcd5f38 r4:8162d1c8 [<8162c37c>] (unix_dgram_recvmsg) from [<8137a210>] (sock_recvmsg_nosec net/socket.c:1046 [inline]) [<8162c37c>] (unix_dgram_recvmsg) from [<8137a210>] (sock_recvmsg+0x50/0x78 net/socket.c:1068) r4:8162c37c [<8137a1c0>] (sock_recvmsg) from [<8137a410>] (____sys_recvmsg+0x90/0x158 net/socket.c:2803) r7:00000000 r6:200004c0 r5:831e2780 r4:dfcd5f38 [<8137a380>] (____sys_recvmsg) from [<8137d354>] (___sys_recvmsg+0x88/0xbc net/socket.c:2845) r10:00000129 r9:84756c00 r8:831e2780 r7:00000102 r6:200004c0 r5:dfcd5f38 r4:00000000 [<8137d2cc>] (___sys_recvmsg) from [<8137dad0>] (__sys_recvmsg net/socket.c:2875 [inline]) [<8137d2cc>] (___sys_recvmsg) from [<8137dad0>] (__do_sys_recvmsg net/socket.c:2885 [inline]) [<8137d2cc>] (___sys_recvmsg) from [<8137dad0>] (sys_recvmsg+0x74/0xb8 net/socket.c:2882) r8:80200288 r7:00000102 r6:200004c0 r5:00000000 r4:831e2780 [<8137da5c>] (sys_recvmsg) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:66) Exception stack(0xdfcd5fa8 to 0xdfcd5ff0) 5fa0: 00000000 00000000 00000003 200004c0 00000102 00000000 5fc0: 00000000 00000000 0014c2c8 00000129 7ed0432e 7ed0432f 003d0f00 76bea0fc 5fe0: 76be9f08 76be9ef8 000167f8 00050bc0 r7:00000129 r6:0014c2c8 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