8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 00000000 when read [00000000] *pgd=85510003, *pmd=ea848003 Internal error: Oops: 207 [#1] PREEMPT SMP ARM Modules linked in: CPU: 0 PID: 3636 Comm: syz-executor.1 Not tainted 6.9.0-rc5-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 : [<8047a244>] lr : [<807e9cdc>] psr: 60000013 sp : dfd25c20 ip : dfd25c30 fp : dfd25c2c r10: 00000018 r9 : 8285a4e8 r8 : 00000000 r7 : 00000000 r6 : 00000000 r5 : 00000000 r4 : 84116800 r3 : 00c00000 r2 : 0000071f r1 : 00000000 r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 8511d900 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 84116800 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 0xdfd24000 allocated at create_io_thread+0x68/0x98 kernel/fork.c:2745 Register r12 information: 2-page vmalloc region starting at 0xdfd24000 allocated at create_io_thread+0x68/0x98 kernel/fork.c:2745 Process syz-executor.1 (pid: 3636, stack limit = 0xdfd24000) Stack: (0xdfd25c20 to 0xdfd26000) 5c20: dfd25c64 dfd25c30 807e9cdc 8047a244 dfd25c54 dfd25ef0 8024c860 84116800 5c40: 84116800 00000000 00000000 00000000 00000041 00000018 dfd25cb4 dfd25c68 5c60: 81433d4c 807e9bf0 dfd25cec dfd25c78 84f47e00 84f47ed0 85433600 84f47ed8 5c80: dfd25ef0 00000000 dfd25c94 85433600 00000041 84f47e00 85612400 00000000 5ca0: 00000000 00000000 dfd25d24 dfd25cb8 81656a58 81433c68 00000000 dfd25ee0 5cc0: 00000000 846dcaab dfe62000 821a9848 85433688 84f47eec 85433834 dfd25ee0 5ce0: dfd25ee0 84819900 00000000 00000000 00000000 846dcaab dfd25d24 81656908 5d00: 84819900 20000d60 81655a9c 00000000 00000000 dfd25d54 dfd25d44 dfd25d28 5d20: 81655ad4 81656914 00000000 84819900 20000d40 dfd25ee0 dfd25e04 dfd25d48 5d40: 813a3640 81655aa8 00000000 00000000 00000001 00000000 00000000 00000000 5d60: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 5d80: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 5da0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 5dc0: 00000000 00000000 00000000 00000000 00000000 846dcaab 00000000 00000000 5de0: dfd25ee0 20000d60 00000000 84819900 85612400 00000002 dfd25e84 dfd25e08 5e00: 813a64e0 813a3518 00000000 00000001 8031cab4 00000000 00000000 20000500 5e20: 00000041 00000000 00000000 00000000 00000000 00000000 00000000 00000000 5e40: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 846dcaab 5e60: dfd25e84 dfd25ec0 20000d60 00000001 00000000 00000000 dfd25f5c dfd25e88 5e80: 813a6608 813a6464 00000001 dfd25e98 8089ad48 84819900 00000001 00000000 5ea0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 5ec0: 00000000 00000000 00050bf0 00000000 00000000 00000000 dfd25f04 dfd25ee8 5ee0: dfd25d54 00000000 00000000 00000000 00000000 00000000 20000500 00000041 5f00: 00000001 00000000 00000000 00000001 00000000 00000000 00000000 00000000 5f20: 00000000 00000000 dfd25f44 846dcaab 818c0ff0 00000003 20000d40 00000000 5f40: 00000000 00000002 85612400 0000016d dfd25fa4 dfd25f60 813a6f9c 813a6520 5f60: 00000000 dfd25fb0 00000000 00000000 00000000 00000000 dfd25fac 846dcaab 5f80: 8020ca6c 00000000 00000000 0014c2d0 0000016d 80200288 00000000 dfd25fa8 5fa0: 80200060 813a6ee4 00000000 00000000 00000003 20000d40 00000002 00000000 5fc0: 00000000 00000000 0014c2d0 0000016d 7efe732e 7efe732f 003d0f00 76b350fc 5fe0: 76b34f08 76b34ef8 00016ab0 00050bf0 60000010 00000003 00000000 00000000 Call trace: [<8047a238>] (__kmap_local_page_prot) from [<807e9cdc>] (kmap_local_page include/linux/highmem-internal.h:73 [inline]) [<8047a238>] (__kmap_local_page_prot) from [<807e9cdc>] (copy_page_to_iter+0xf8/0x184 lib/iov_iter.c:360) [<807e9be4>] (copy_page_to_iter) from [<81433d4c>] (sk_msg_recvmsg+0xf0/0x3cc net/core/skmsg.c:437) r10:00000018 r9:00000041 r8:00000000 r7:00000000 r6:00000000 r5:84116800 r4:84116800 [<81433c5c>] (sk_msg_recvmsg) from [<81656a58>] (unix_bpf_recvmsg net/unix/unix_bpf.c:73 [inline]) [<81433c5c>] (sk_msg_recvmsg) from [<81656a58>] (unix_bpf_recvmsg+0x150/0x444 net/unix/unix_bpf.c:50) r10:00000000 r9:00000000 r8:00000000 r7:85612400 r6:84f47e00 r5:00000041 r4:85433600 [<81656908>] (unix_bpf_recvmsg) from [<81655ad4>] (unix_dgram_recvmsg+0x38/0x4c net/unix/af_unix.c:2529) r10:dfd25d54 r9:00000000 r8:00000000 r7:81655a9c r6:20000d60 r5:84819900 r4:81656908 [<81655a9c>] (unix_dgram_recvmsg) from [<813a3640>] (sock_recvmsg_nosec net/socket.c:1046 [inline]) [<81655a9c>] (unix_dgram_recvmsg) from [<813a3640>] (____sys_recvmsg+0x134/0x158 net/socket.c:2801) r4:dfd25ee0 [<813a350c>] (____sys_recvmsg) from [<813a64e0>] (___sys_recvmsg+0x88/0xbc net/socket.c:2845) r10:00000002 r9:85612400 r8:84819900 r7:00000000 r6:20000d60 r5:dfd25ee0 r4:00000000 [<813a6458>] (___sys_recvmsg) from [<813a6608>] (do_recvmmsg+0xf4/0x298 net/socket.c:2939) r8:00000000 r7:00000000 r6:00000001 r5:20000d60 r4:dfd25ec0 [<813a6514>] (do_recvmmsg) from [<813a6f9c>] (__sys_recvmmsg net/socket.c:3018 [inline]) [<813a6514>] (do_recvmmsg) from [<813a6f9c>] (__do_sys_recvmmsg_time32 net/socket.c:3052 [inline]) [<813a6514>] (do_recvmmsg) from [<813a6f9c>] (sys_recvmmsg_time32+0xc4/0xd8 net/socket.c:3045) r10:0000016d r9:85612400 r8:00000002 r7:00000000 r6:00000000 r5:20000d40 r4:00000003 [<813a6ed8>] (sys_recvmmsg_time32) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:66) Exception stack(0xdfd25fa8 to 0xdfd25ff0) 5fa0: 00000000 00000000 00000003 20000d40 00000002 00000000 5fc0: 00000000 00000000 0014c2d0 0000016d 7efe732e 7efe732f 003d0f00 76b350fc 5fe0: 76b34f08 76b34ef8 00016ab0 00050bf0 r8:80200288 r7:0000016d r6:0014c2d0 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