8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 00000008 when read [00000008] *pgd=8770b003, *pmd=f3c94003 Internal error: Oops: 205 [#1] PREEMPT SMP ARM Modules linked in: CPU: 1 PID: 1100 Comm: syz.0.41874 Not tainted 6.10.0-syzkaller #0 Hardware name: ARM-Versatile Express PC is at path_from_stashed+0x1c/0x308 fs/libfs.c:2204 LR is at open_namespace+0x44/0xbc fs/nsfs.c:102 pc : [<8053af54>] lr : [<8054d6f8>] psr: 80000013 sp : e02b9e80 ip : 8539d400 fp : e02b9ec4 r10: 8539d400 r9 : 00000003 r8 : 871209c0 r7 : 82caa250 r6 : 8539d400 r5 : 00000000 r4 : 852b55a0 r3 : e02b9ecc r2 : 00000008 r1 : 82c95800 r0 : 00000008 Flags: Nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 858ccc00 DAC: 00000000 Register r0 information: non-paged memory Register r1 information: slab kmalloc-1k start 82c95800 pointer offset 0 size 1024 Register r2 information: non-paged memory Register r3 information: 2-page vmalloc region starting at 0xe02b8000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2780 Register r4 information: slab anon_vma_chain start 852b55a0 pointer offset 0 size 40 Register r5 information: NULL pointer Register r6 information: slab task_struct start 8539d400 pointer offset 0 size 3072 Register r7 information: slab mnt_cache start 82caa240 pointer offset 16 size 184 Register r8 information: slab filp start 871209c0 pointer offset 0 size 160 Register r9 information: non-paged memory Register r10 information: slab task_struct start 8539d400 pointer offset 0 size 3072 Register r11 information: 2-page vmalloc region starting at 0xe02b8000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2780 Register r12 information: slab task_struct start 8539d400 pointer offset 0 size 3072 Process syz.0.41874 (pid: 1100, stack limit = 0xe02b8000) Stack: (0xe02b9e80 to 0xe02ba000) 9e80: 8539ec00 00000008 e02b9eb4 e02b9e98 806e6544 804065ac 00000009 852b55a0 9ea0: 00000000 8539d400 8539f480 871209c0 00000003 8539d400 e02b9ef4 e02b9ec8 9ec0: 8054d6f8 8053af44 e02b9ef4 00000000 00000000 0a32edd9 852b55a0 852b55a0 9ee0: 8539ec00 00000008 e02b9f14 e02b9ef8 8055271c 8054d6c0 0000ff08 00000000 9f00: 871209c1 00000000 e02b9fa4 e02b9f18 8051a7f0 805525a4 8539d400 00000001 9f20: ecac8b10 8539d400 e02b9f44 e02b9f38 81903eac 81903d7c e02b9f5c e02b9f48 9f40: 8024b544 8027aebc 40000000 e02b9fb0 e02b9f84 e02b9f60 80202dd8 8024b500 9f60: 8261c90c e02b9fb0 0014aa30 ecac8b10 80202cc0 0a32edd9 e02b9fac 00000000 9f80: 00000000 002642dc 00000036 8020029c 8539d400 00000036 00000000 e02b9fa8 9fa0: 80200060 8051a6c8 00000000 00000000 00000003 0000ff08 00000000 00000000 9fc0: 00000000 00000000 002642dc 00000036 7eb99766 7eb99767 003d0f00 76b760bc 9fe0: 76b75ec8 76b75eb8 000183ec 00130580 60000010 00000003 00000000 00000000 Call trace: [<8053af38>] (path_from_stashed) from [<8054d6f8>] (open_namespace+0x44/0xbc fs/nsfs.c:102) r10:8539d400 r9:00000003 r8:871209c0 r7:8539f480 r6:8539d400 r5:00000000 r4:852b55a0 [<8054d6b4>] (open_namespace) from [<8055271c>] (pidfd_ioctl+0x184/0x4c4 fs/pidfs.c:196) r6:00000008 r5:8539ec00 r4:852b55a0 [<80552598>] (pidfd_ioctl) from [<8051a7f0>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<80552598>] (pidfd_ioctl) from [<8051a7f0>] (do_vfs_ioctl fs/ioctl.c:861 [inline]) [<80552598>] (pidfd_ioctl) from [<8051a7f0>] (__do_sys_ioctl fs/ioctl.c:905 [inline]) [<80552598>] (pidfd_ioctl) from [<8051a7f0>] (sys_ioctl+0x134/0xda4 fs/ioctl.c:893) r7:00000000 r6:871209c1 r5:00000000 r4:0000ff08 [<8051a6bc>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe02b9fa8 to 0xe02b9ff0) 9fa0: 00000000 00000000 00000003 0000ff08 00000000 00000000 9fc0: 00000000 00000000 002642dc 00000036 7eb99766 7eb99767 003d0f00 76b760bc 9fe0: 76b75ec8 76b75eb8 000183ec 00130580 r10:00000036 r9:8539d400 r8:8020029c r7:00000036 r6:002642dc r5:00000000 r4:00000000 Code: e24dd01c e1a07001 e5911004 ee1dcf70 (e5905000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e24dd01c sub sp, sp, #28 4: e1a07001 mov r7, r1 8: e5911004 ldr r1, [r1, #4] c: ee1dcf70 mrc 15, 0, ip, cr13, cr0, {3} * 10: e5905000 ldr r5, [r0] <-- trapping instruction