8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 00000000 when read [00000000] *pgd=87075003, *pmd=feb6e003 Internal error: Oops: 207 [#1] PREEMPT SMP ARM Modules linked in: CPU: 1 PID: 14945 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:1097 [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 : [<80477748>] lr : [<807e2e64>] psr: 60000013 sp : dfb49ca0 ip : dfb49cb0 fp : dfb49cac r10: 00000018 r9 : 828514e8 r8 : 00000000 r7 : 00000000 r6 : 00000000 r5 : 00000000 r4 : 84844400 r3 : 00c00000 r2 : 0000071f r1 : 00000000 r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 855ce040 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 84844400 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 0xdfb48000 allocated at kernel_clone+0xac/0x3cc kernel/fork.c:2796 Register r12 information: 2-page vmalloc region starting at 0xdfb48000 allocated at kernel_clone+0xac/0x3cc kernel/fork.c:2796 Process syz-executor.1 (pid: 14945, stack limit = 0xdfb48000) Stack: (0xdfb49ca0 to 0xdfb4a000) 9ca0: dfb49ce4 dfb49cb0 807e2e64 80477748 dfb49cd4 dfb49f48 8024c6c4 84844400 9cc0: 84844400 00000000 00000001 00000000 000000c7 00000018 dfb49d34 dfb49ce8 9ce0: 813efe74 807e2d78 00000000 ce0461b5 845b7000 845b70d0 82e21e00 845b70d8 9d00: dfb49f48 00000002 dfb49d8c 82e21e00 000000c7 845b7000 8373e000 00000000 9d20: 00000102 00000000 dfb49da4 dfb49d38 81612574 813efd90 00000102 00000000 9d40: 00000000 00000000 00000000 00000000 82e21e88 845b70ec 82e22034 dfb49f38 9d60: 00000000 ce0461b5 8187b580 82193840 00000102 ce0461b5 dfb49f38 81612424 9d80: dfb49f38 84c56500 00000102 00000000 00000102 dfb49df4 dfb49dc4 dfb49da8 9da0: 81611610 81612430 00000000 00000102 00000000 816115d8 dfb49de4 dfb49dc8 9dc0: 8136070c 816115e4 dfb49f38 84c56500 200004c0 00000000 dfb49ea4 dfb49de8 9de0: 8136090c 813606c8 00000000 00000000 00000001 00000000 00000000 00000000 9e00: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 9e20: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 9e40: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 9e60: 00000000 00000000 00000000 00000000 00000000 ce0461b5 00000000 00000000 9e80: dfb49f38 200004c0 00000102 84c56500 8373e000 00000129 dfb49f24 dfb49ea8 9ea0: 81363850 81360888 00000102 00000000 00000008 00000000 00000000 200002c0 9ec0: 000000c7 00000000 00000000 00000000 00000000 00000000 00000000 00000000 9ee0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 ce0461b5 9f00: dfb49f24 84c56500 00000000 200004c0 00000102 80200288 dfb49fa4 dfb49f28 9f20: 81364008 813637d4 00000000 dfb49f38 00000001 fffffff7 dfb49df4 00000000 9f40: 00000000 00000000 00000000 00000001 200002c0 000000c6 00000001 00000000 9f60: 00000000 00000001 00000000 00000000 00000000 00000000 00000000 00000000 9f80: 8020ca5c ce0461b5 00000000 00000000 0014c2c8 00000129 00000000 dfb49fa8 9fa0: 80200060 81363fa0 00000000 00000000 00000003 200004c0 00000102 00000000 9fc0: 00000000 00000000 0014c2c8 00000129 7e88932e 7e88932f 003d0f00 76b260fc 9fe0: 76b25f08 76b25ef8 000167f8 00050bc0 60000010 00000003 00000000 00000000 Backtrace: [<8047773c>] (__kmap_local_page_prot) from [<807e2e64>] (kmap_local_page include/linux/highmem-internal.h:73 [inline]) [<8047773c>] (__kmap_local_page_prot) from [<807e2e64>] (copy_page_to_iter+0xf8/0x184 lib/iov_iter.c:360) [<807e2d6c>] (copy_page_to_iter) from [<813efe74>] (sk_msg_recvmsg+0xf0/0x3cc net/core/skmsg.c:437) r10:00000018 r9:000000c7 r8:00000000 r7:00000001 r6:00000000 r5:84844400 r4:84844400 [<813efd84>] (sk_msg_recvmsg) from [<81612574>] (unix_bpf_recvmsg net/unix/unix_bpf.c:73 [inline]) [<813efd84>] (sk_msg_recvmsg) from [<81612574>] (unix_bpf_recvmsg+0x150/0x444 net/unix/unix_bpf.c:50) r10:00000000 r9:00000102 r8:00000000 r7:8373e000 r6:845b7000 r5:000000c7 r4:82e21e00 [<81612424>] (unix_bpf_recvmsg) from [<81611610>] (unix_dgram_recvmsg+0x38/0x4c net/unix/af_unix.c:2529) r10:dfb49df4 r9:00000102 r8:00000000 r7:00000102 r6:84c56500 r5:dfb49f38 r4:81612424 [<816115d8>] (unix_dgram_recvmsg) from [<8136070c>] (sock_recvmsg_nosec net/socket.c:1046 [inline]) [<816115d8>] (unix_dgram_recvmsg) from [<8136070c>] (sock_recvmsg+0x50/0x78 net/socket.c:1068) r4:816115d8 [<813606bc>] (sock_recvmsg) from [<8136090c>] (____sys_recvmsg+0x90/0x158 net/socket.c:2803) r7:00000000 r6:200004c0 r5:84c56500 r4:dfb49f38 [<8136087c>] (____sys_recvmsg) from [<81363850>] (___sys_recvmsg+0x88/0xbc net/socket.c:2845) r10:00000129 r9:8373e000 r8:84c56500 r7:00000102 r6:200004c0 r5:dfb49f38 r4:00000000 [<813637c8>] (___sys_recvmsg) from [<81364008>] (__sys_recvmsg net/socket.c:2875 [inline]) [<813637c8>] (___sys_recvmsg) from [<81364008>] (__do_sys_recvmsg net/socket.c:2885 [inline]) [<813637c8>] (___sys_recvmsg) from [<81364008>] (sys_recvmsg+0x74/0xb8 net/socket.c:2882) r8:80200288 r7:00000102 r6:200004c0 r5:00000000 r4:84c56500 [<81363f94>] (sys_recvmsg) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:66) Exception stack(0xdfb49fa8 to 0xdfb49ff0) 9fa0: 00000000 00000000 00000003 200004c0 00000102 00000000 9fc0: 00000000 00000000 0014c2c8 00000129 7e88932e 7e88932f 003d0f00 76b260fc 9fe0: 76b25f08 76b25ef8 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