8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 00000000 when read [00000000] *pgd=87928003, *pmd=fec34003 Internal error: Oops: 207 [#1] PREEMPT SMP ARM Modules linked in: CPU: 0 PID: 15186 Comm: syz-executor.0 Not tainted 6.8.0-rc1-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:379 pc : [<8046cedc>] lr : [<807d34b8>] psr: 60000013 sp : dfc9dca0 ip : dfc9dcb0 fp : dfc9dcac r10: 00000018 r9 : 8284f4e8 r8 : 00000000 r7 : 00000000 r6 : 00000000 r5 : 00000000 r4 : 876db800 r3 : 00c00000 r2 : 0000071f r1 : 00000000 r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 837aba40 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 876db800 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 0xdfc9c000 allocated at kernel_clone+0xac/0x3c8 kernel/fork.c:2901 Register r12 information: 2-page vmalloc region starting at 0xdfc9c000 allocated at kernel_clone+0xac/0x3c8 kernel/fork.c:2901 Process syz-executor.0 (pid: 15186, stack limit = 0xdfc9c000) Stack: (0xdfc9dca0 to 0xdfc9e000) dca0: dfc9dce4 dfc9dcb0 807d34b8 8046cedc dfc9dcd4 dfc9df48 8024c824 876db800 dcc0: 876db800 00000000 00000000 00000000 000000e9 00000018 dfc9dd34 dfc9dce8 dce0: 813d84e4 807d33cc 00000000 3eb37bfb 8695f800 8695f8d0 82f29500 8695f8d8 dd00: dfc9df48 00000000 dfc9dd8c 82f29500 000000e9 8695f800 87973c00 00000000 dd20: 00000000 00000000 dfc9dda4 dfc9dd38 815f6228 813d8400 00000000 00000000 dd40: 00000000 00000000 00000000 00000000 82f295a8 8695f8ec 82f29734 dfc9df38 dd60: 00000000 3eb37bfb 81857168 821907f4 00000000 3eb37bfb dfc9df38 815f60d8 dd80: dfc9df38 84964a00 00000000 00000000 00000000 dfc9ddf4 dfc9ddc4 dfc9dda8 dda0: 815f5568 815f60e4 00000000 00000000 00000000 815f5530 dfc9dde4 dfc9ddc8 ddc0: 8134b868 815f553c dfc9df38 84964a00 20000800 00000000 dfc9dea4 dfc9dde8 dde0: 8134ba6c 8134b824 00000000 00000000 00000001 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 3eb37bfb 00000000 00000000 de80: dfc9df38 20000800 00000000 84964a00 87973c00 00000129 dfc9df24 dfc9dea8 dea0: 8134e984 8134b9e8 00000000 00000000 00000008 00000000 00000000 20000640 dec0: 000000e9 00000000 00000000 00000000 00000000 00000000 00000000 00000000 dee0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 3eb37bfb df00: dfc9df24 84964a00 00000000 20000800 00000000 80200288 dfc9dfa4 dfc9df28 df20: 8134f13c 8134e908 00000000 dfc9df38 00000001 fffffff7 dfc9ddf4 00000000 df40: 00000000 00000000 00000000 00000000 20000640 000000e9 00000001 00000000 df60: 00000000 00000001 00000000 00000000 00000000 00000000 00000000 00000000 df80: 8020ca34 3eb37bfb 00000000 00000000 0014c2c8 00000129 00000000 dfc9dfa8 dfa0: 80200060 8134f0d4 00000000 00000000 00000005 20000800 00000000 00000000 dfc0: 00000000 00000000 0014c2c8 00000129 7eb8f326 7eb8f327 003d0f00 76bc70fc dfe0: 76bc6f08 76bc6ef8 000167e8 00050bd0 60000010 00000005 00000000 00000000 Backtrace: [<8046ced0>] (__kmap_local_page_prot) from [<807d34b8>] (kmap_local_page include/linux/highmem-internal.h:73 [inline]) [<8046ced0>] (__kmap_local_page_prot) from [<807d34b8>] (copy_page_to_iter+0xf8/0x184 lib/iov_iter.c:379) [<807d33c0>] (copy_page_to_iter) from [<813d84e4>] (sk_msg_recvmsg+0xf0/0x3cc net/core/skmsg.c:437) r10:00000018 r9:000000e9 r8:00000000 r7:00000000 r6:00000000 r5:876db800 r4:876db800 [<813d83f4>] (sk_msg_recvmsg) from [<815f6228>] (unix_bpf_recvmsg net/unix/unix_bpf.c:73 [inline]) [<813d83f4>] (sk_msg_recvmsg) from [<815f6228>] (unix_bpf_recvmsg+0x150/0x444 net/unix/unix_bpf.c:50) r10:00000000 r9:00000000 r8:00000000 r7:87973c00 r6:8695f800 r5:000000e9 r4:82f29500 [<815f60d8>] (unix_bpf_recvmsg) from [<815f5568>] (unix_dgram_recvmsg+0x38/0x4c net/unix/af_unix.c:2483) r10:dfc9ddf4 r9:00000000 r8:00000000 r7:00000000 r6:84964a00 r5:dfc9df38 r4:815f60d8 [<815f5530>] (unix_dgram_recvmsg) from [<8134b868>] (sock_recvmsg_nosec net/socket.c:1046 [inline]) [<815f5530>] (unix_dgram_recvmsg) from [<8134b868>] (sock_recvmsg+0x50/0x78 net/socket.c:1068) r4:815f5530 [<8134b818>] (sock_recvmsg) from [<8134ba6c>] (____sys_recvmsg+0x90/0x158 net/socket.c:2803) r7:00000000 r6:20000800 r5:84964a00 r4:dfc9df38 [<8134b9dc>] (____sys_recvmsg) from [<8134e984>] (___sys_recvmsg+0x88/0xbc net/socket.c:2845) r10:00000129 r9:87973c00 r8:84964a00 r7:00000000 r6:20000800 r5:dfc9df38 r4:00000000 [<8134e8fc>] (___sys_recvmsg) from [<8134f13c>] (__sys_recvmsg net/socket.c:2875 [inline]) [<8134e8fc>] (___sys_recvmsg) from [<8134f13c>] (__do_sys_recvmsg net/socket.c:2885 [inline]) [<8134e8fc>] (___sys_recvmsg) from [<8134f13c>] (sys_recvmsg+0x74/0xb8 net/socket.c:2882) r8:80200288 r7:00000000 r6:20000800 r5:00000000 r4:84964a00 [<8134f0c8>] (sys_recvmsg) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:66) Exception stack(0xdfc9dfa8 to 0xdfc9dff0) dfa0: 00000000 00000000 00000005 20000800 00000000 00000000 dfc0: 00000000 00000000 0014c2c8 00000129 7eb8f326 7eb8f327 003d0f00 76bc70fc dfe0: 76bc6f08 76bc6ef8 000167e8 00050bd0 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