8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 00000000 when read [00000000] *pgd=84743003, *pmd=fe6cd003 Internal error: Oops: 207 [#1] PREEMPT SMP ARM Modules linked in: CPU: 0 PID: 3935 Comm: syz-executor.0 Not tainted 6.9.0-rc4-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 : [<80479ea8>] lr : [<807e997c>] psr: 60000013 sp : df9f5ca0 ip : df9f5cb0 fp : df9f5cac r10: 00000018 r9 : 8285a4e8 r8 : 00000000 r7 : 00000000 r6 : 00000000 r5 : 00000000 r4 : 8489a400 r3 : 00c00000 r2 : 0000071f r1 : 00000000 r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 848db4c0 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 8489a400 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/0x3cc kernel/fork.c:2796 Register r12 information: 2-page vmalloc region starting at 0xdf9f4000 allocated at kernel_clone+0xac/0x3cc kernel/fork.c:2796 Process syz-executor.0 (pid: 3935, stack limit = 0xdf9f4000) Stack: (0xdf9f5ca0 to 0xdf9f6000) 5ca0: df9f5ce4 df9f5cb0 807e997c 80479ea8 df9f5cd4 df9f5f48 8024c880 8489a400 5cc0: 8489a400 00000000 00000000 00000000 000000d4 00000018 df9f5d34 df9f5ce8 5ce0: 814333f4 807e9890 00000000 6ddd6be4 83fffc00 83fffcd0 83dea700 83fffcd8 5d00: df9f5f48 00000000 df9f5d8c 83dea700 000000d4 83fffc00 8410b000 00000000 5d20: 00000000 00000000 df9f5da4 df9f5d38 816560a8 81433310 00000000 00000000 5d40: 00000000 00000000 00000000 00000000 83dea788 83fffcec 83dea934 df9f5f38 5d60: 00000000 6ddd6be4 818c33d0 821a9848 00000000 6ddd6be4 df9f5f38 81655f58 5d80: df9f5f38 83372780 00000000 00000000 00000000 df9f5df4 df9f5dc4 df9f5da8 5da0: 81655124 81655f64 00000000 00000000 00000000 816550ec df9f5de4 df9f5dc8 5dc0: 813a29d4 816550f8 df9f5f38 83372780 200001c0 00000000 df9f5ea4 df9f5de8 5de0: 813a2bd4 813a2990 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 6ddd6be4 00000000 00000000 5e80: df9f5f38 200001c0 00000000 83372780 8410b000 00000129 df9f5f24 df9f5ea8 5ea0: 813a5b18 813a2b50 00000000 00000000 00000008 00000000 00000000 20000280 5ec0: 000000d4 00000000 00000000 00000000 00000000 00000000 00000000 00000000 5ee0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 6ddd6be4 5f00: df9f5f24 83372780 00000000 200001c0 00000000 80200288 df9f5fa4 df9f5f28 5f20: 813a6294 813a5a9c 00000000 df9f5f38 00000001 fffffff7 df9f5df4 00000000 5f40: 00000000 00000000 00000000 00000000 20000280 000000d4 00000001 00000000 5f60: 00000000 00000001 00000000 00000000 00000000 00000000 00000000 00000000 5f80: 8020ca6c 6ddd6be4 00000000 00000000 0014c2c8 00000129 00000000 df9f5fa8 5fa0: 80200060 813a622c 00000000 00000000 00000003 200001c0 00000000 00000000 5fc0: 00000000 00000000 0014c2c8 00000129 7ee5432e 7ee5432f 003d0f00 76b1d0fc 5fe0: 76b1cf08 76b1cef8 000168a0 00050c70 60000010 00000003 00000000 00000000 Call trace: [<80479e9c>] (__kmap_local_page_prot) from [<807e997c>] (kmap_local_page include/linux/highmem-internal.h:73 [inline]) [<80479e9c>] (__kmap_local_page_prot) from [<807e997c>] (copy_page_to_iter+0xf8/0x184 lib/iov_iter.c:360) [<807e9884>] (copy_page_to_iter) from [<814333f4>] (sk_msg_recvmsg+0xf0/0x3cc net/core/skmsg.c:437) r10:00000018 r9:000000d4 r8:00000000 r7:00000000 r6:00000000 r5:8489a400 r4:8489a400 [<81433304>] (sk_msg_recvmsg) from [<816560a8>] (unix_bpf_recvmsg net/unix/unix_bpf.c:73 [inline]) [<81433304>] (sk_msg_recvmsg) from [<816560a8>] (unix_bpf_recvmsg+0x150/0x444 net/unix/unix_bpf.c:50) r10:00000000 r9:00000000 r8:00000000 r7:8410b000 r6:83fffc00 r5:000000d4 r4:83dea700 [<81655f58>] (unix_bpf_recvmsg) from [<81655124>] (unix_dgram_recvmsg+0x38/0x4c net/unix/af_unix.c:2529) r10:df9f5df4 r9:00000000 r8:00000000 r7:00000000 r6:83372780 r5:df9f5f38 r4:81655f58 [<816550ec>] (unix_dgram_recvmsg) from [<813a29d4>] (sock_recvmsg_nosec net/socket.c:1046 [inline]) [<816550ec>] (unix_dgram_recvmsg) from [<813a29d4>] (sock_recvmsg+0x50/0x78 net/socket.c:1068) r4:816550ec [<813a2984>] (sock_recvmsg) from [<813a2bd4>] (____sys_recvmsg+0x90/0x158 net/socket.c:2803) r7:00000000 r6:200001c0 r5:83372780 r4:df9f5f38 [<813a2b44>] (____sys_recvmsg) from [<813a5b18>] (___sys_recvmsg+0x88/0xbc net/socket.c:2845) r10:00000129 r9:8410b000 r8:83372780 r7:00000000 r6:200001c0 r5:df9f5f38 r4:00000000 [<813a5a90>] (___sys_recvmsg) from [<813a6294>] (__sys_recvmsg net/socket.c:2875 [inline]) [<813a5a90>] (___sys_recvmsg) from [<813a6294>] (__do_sys_recvmsg net/socket.c:2885 [inline]) [<813a5a90>] (___sys_recvmsg) from [<813a6294>] (sys_recvmsg+0x74/0xb8 net/socket.c:2882) r8:80200288 r7:00000000 r6:200001c0 r5:00000000 r4:83372780 [<813a6220>] (sys_recvmsg) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:66) Exception stack(0xdf9f5fa8 to 0xdf9f5ff0) 5fa0: 00000000 00000000 00000003 200001c0 00000000 00000000 5fc0: 00000000 00000000 0014c2c8 00000129 7ee5432e 7ee5432f 003d0f00 76b1d0fc 5fe0: 76b1cf08 76b1cef8 000168a0 00050c70 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