8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f2c when write [fee04f2c] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 16495 Comm: syz.5.2805 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: ARM-Versatile Express PC is at __raw_writeb arch/arm/include/asm/io.h:88 [inline] PC is at subdev_8255_io drivers/comedi/drivers/comedi_8255.c:47 [inline] PC is at subdev_8255_io+0x60/0x6c drivers/comedi/drivers/comedi_8255.c:43 LR is at subdev_8255_io drivers/comedi/drivers/comedi_8255.c:47 [inline] LR is at subdev_8255_io+0x4c/0x6c drivers/comedi/drivers/comedi_8255.c:43 pc : [<8140e660>] lr : [<8140e64c>] psr: 60000013 sp : e0255cb8 ip : e0255cb8 fp : e0255cd4 r10: 00000000 r9 : 00000084 r8 : e0255da4 r7 : 00004f29 r6 : 0000009b r5 : 8449cf00 r4 : 00004f2c r3 : 0000009b r2 : fee04f2c r1 : 00000001 r0 : 8449cf00 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 854c5700 DAC: fffffffd Register r0 information: slab kmalloc-192 start 8449cf00 pointer offset 0 size 192 Register r1 information: non-paged memory Register r2 information: 0-page vmalloc region starting at 0xfee00000 allocated at pci_reserve_io+0x0/0x38 arch/arm/mm/mmu.c:1055 Register r3 information: non-paged memory Register r4 information: non-paged memory Register r5 information: slab kmalloc-192 start 8449cf00 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: non-paged memory Register r8 information: 2-page vmalloc region starting at 0xe0254000 allocated at kernel_clone+0xac/0x3f4 kernel/fork.c:2651 Register r9 information: non-paged memory Register r10 information: NULL pointer Register r11 information: 2-page vmalloc region starting at 0xe0254000 allocated at kernel_clone+0xac/0x3f4 kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xe0254000 allocated at kernel_clone+0xac/0x3f4 kernel/fork.c:2651 Process syz.5.2805 (pid: 16495, stack limit = 0xe0254000) Stack: (0xe0255cb8 to 0xe0256000) 5ca0: 8140e600 00004f29 5cc0: 8449cf00 00004f29 e0255cf4 e0255cd8 8140e33c 8140e60c 00004f29 e0255cf8 5ce0: 8140e6f4 85c17800 e0255d14 e0255cf8 8140e6f4 8140e2f0 8449cf00 00000000 5d00: 85c17800 00004f29 e0255d54 e0255d18 8140e8a4 8140e678 e0255d6c 83e52b80 5d20: 828215f0 00000000 00000000 829d4c84 8449cf00 00000000 e0255d90 8449cf00 5d40: 00000000 82b29b30 e0255d8c e0255d58 813fd298 8140e83c 40946400 00000000 5d60: e0255d7c 200000c0 8449cf00 b5403587 40946400 845c1800 00000003 8449cf30 5d80: e0255e4c e0255d90 813f8bd0 813fd198 35353238 00000000 00000000 00000000 5da0: 00000000 00004f29 00000005 00000003 00040004 fffffbfd 0000000b 00000004 5dc0: 00000000 00000081 fffffffc 00000002 fffffffe 00000008 00000001 00000004 5de0: 00000101 00000008 000002b0 00000009 00080005 00000099 00400000 00000080 5e00: 00000800 00000007 02000e69 00000006 00080004 00000400 00000000 fffffff8 5e20: 00000000 68c17f46 00000000 861b1600 8449cf00 200000c0 40946400 845c1800 5e40: e0255f14 e0255e50 813f9750 813f8b08 e0255e4c 68c17f46 00000000 00000000 5e60: 824b1574 e0255ea4 0000005f 84240a30 00000064 844b687c e0255ee4 e0255e88 5e80: 807b43fc 807aaa78 00000064 00000001 00000000 e0255ea4 861040d0 834ea660 5ea0: 00006400 0000000b e0255e98 00000000 e0255d38 68c17f46 00000000 861b1600 5ec0: 40946400 200000c0 200000c0 861b1600 00000003 845c1800 e0255ef4 e0255ee8 5ee0: 807b452c 68c17f46 e0255f14 00000000 861b1601 40946400 200000c0 861b1600 5f00: 00000003 845c1800 e0255fa4 e0255f18 80582358 813f9658 ecac8b10 845c1800 5f20: e0255f3c e0255f30 81aa745c 81aa732c e0255f54 e0255f40 8025ba7c 8028ef68 5f40: e0255fb0 40000000 e0255f84 e0255f58 80221a54 8025ba38 00000000 8281cfbc 5f60: e0255fb0 0013ddc0 ecac8b10 802219a8 00000000 68c17f46 e0255fac 00000000 5f80: 00000000 00346310 00000036 8020029c 845c1800 00000036 00000000 e0255fa8 5fa0: 80200060 80582120 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f230dc 5fe0: 76f22e88 76f22e78 00018734 0012fc20 60000010 00000003 00000000 00000000 Call trace: [<8140e600>] (subdev_8255_io) from [<8140e33c>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f29 r6:8449cf00 r5:00004f29 r4:8140e600 [<8140e2e4>] (subdev_8255_do_config) from [<8140e6f4>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<8140e2e4>] (subdev_8255_do_config) from [<8140e6f4>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:85c17800 [<8140e66c>] (subdev_8255_io_init) from [<8140e8a4>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<8140e66c>] (subdev_8255_io_init) from [<8140e8a4>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00004f29 r6:85c17800 r5:00000000 r4:8449cf00 [<8140e830>] (dev_8255_attach) from [<813fd298>] (comedi_device_attach+0x10c/0x248 drivers/comedi/drivers.c:1069) r10:82b29b30 r9:00000000 r8:8449cf00 r7:e0255d90 r6:00000000 r5:8449cf00 r4:829d4c84 [<813fd18c>] (comedi_device_attach) from [<813f8bd0>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:928) r10:8449cf30 r9:00000003 r8:845c1800 r7:40946400 r6:b5403587 r5:8449cf00 r4:200000c0 [<813f8afc>] (do_devconfig_ioctl) from [<813f9750>] (comedi_unlocked_ioctl+0x104/0x1c80 drivers/comedi/comedi_fops.c:2240) r8:845c1800 r7:40946400 r6:200000c0 r5:8449cf00 r4:861b1600 [<813f964c>] (comedi_unlocked_ioctl) from [<80582358>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813f964c>] (comedi_unlocked_ioctl) from [<80582358>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813f964c>] (comedi_unlocked_ioctl) from [<80582358>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813f964c>] (comedi_unlocked_ioctl) from [<80582358>] (sys_ioctl+0x244/0xb58 fs/ioctl.c:583) r10:845c1800 r9:00000003 r8:861b1600 r7:200000c0 r6:40946400 r5:861b1601 r4:00000000 [<80582114>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe0255fa8 to 0xe0255ff0) 5fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f230dc 5fe0: 76f22e88 76f22e78 00018734 0012fc20 r10:00000036 r9:845c1800 r8:8020029c r7:00000036 r6:00346310 r5:00000000 r4:00000000 Code: e6ef3076 e0842002 e7f32052 e2422612 (e5c23000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e6ef3076 uxtb r3, r6 4: e0842002 add r2, r4, r2 8: e7f32052 ubfx r2, r2, #0, #20 c: e2422612 sub r2, r2, #18874368 @ 0x1200000 * 10: e5c23000 strb r3, [r2] <-- trapping instruction