8<--- cut here --- Unable to handle kernel paging request at virtual address fee00007 when write [fee00007] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 11276 Comm: syz.3.1830 Not tainted syzkaller #0 PREEMPT Hardware name: ARM-Versatile Express PC is at __raw_writeb arch/arm/include/asm/io.h:99 [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 : [<814ad81c>] lr : [<814ad808>] psr: 60000013 sp : dfb59cb8 ip : dfb59cb8 fp : dfb59cd4 r10: 00000004 r9 : 00000004 r8 : dfb59da4 r7 : 00000000 r6 : 0000009b r5 : 831d3f00 r4 : 00000007 r3 : 0000009b r2 : fee00007 r1 : 00000001 r0 : 831d3f00 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 866ceb80 DAC: fffffffd Register r0 information: slab kmalloc-192 start 831d3f00 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:1048 Register r3 information: non-paged memory Register r4 information: non-paged memory Register r5 information: slab kmalloc-192 start 831d3f00 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: NULL pointer Register r8 information: 2-page vmalloc region starting at 0xdfb58000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2766 Register r9 information: non-paged memory Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xdfb58000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2766 Register r12 information: 2-page vmalloc region starting at 0xdfb58000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2766 Process syz.3.1830 (pid: 11276, stack limit = 0xdfb58000) Stack: (0xdfb59cb8 to 0xdfb5a000) 9ca0: 814ad7bc 00000004 9cc0: 831d3f00 00000000 dfb59cf4 dfb59cd8 814ad4f8 814ad7c8 00000004 80547798 9ce0: 863e9000 863e9000 dfb59d14 dfb59cf8 814ad8b0 814ad4ac 831d3f00 00000000 9d00: 863e9000 00000000 dfb59d54 dfb59d18 814ada60 814ad834 ffffffff 00000004 9d20: 82a22dc0 00000000 00000000 82bdac60 831d3f00 00000000 dfb59d90 831d3f00 9d40: 00000000 82d32f9c dfb59d8c dfb59d58 8149c3e8 814ad9f8 40946400 00000000 9d60: dfb59d7c 20000080 831d3f00 b5403587 40946400 00000001 00000003 83be3100 9d80: dfb59e4c dfb59d90 81497bec 8149c2ec 35353238 00000000 00000000 00000000 9da0: 00000000 00000004 00000005 00000004 00000020 14000000 00000020 00000003 9dc0: 00000008 00000efd 00007ffe 00000008 00000016 00001000 00000002 00000013 9de0: 4000bd55 00000003 0000003c 00000351 00000006 000003ff 0000000a 7fffffff 9e00: 00000860 00000002 00000000 00000004 00000000 0000000a 00000f58 000002cf 9e20: 00000000 ac5484f9 00000000 86101300 831d3f00 20000080 40946400 00000001 9e40: dfb59f14 dfb59e50 81498f14 81497b2c 00000000 ac5484f9 00000000 00000000 9e60: 8254e844 dfb59ea4 0000005f 843007b8 00000064 831d3f30 dfb59ee4 dfb59e88 9e80: 8080b76c 80801e24 00000064 00000001 00000000 dfb59ea4 84eff410 83418220 9ea0: 00006400 0000000b dfb59e98 00000000 00000000 ac5484f9 5b4fd000 86101300 9ec0: 40946400 20000080 20000080 86101300 00000003 83be3100 dfb59ef4 dfb59ee8 9ee0: 8080b8a0 ac5484f9 dfb59f14 00000000 86101301 40946400 20000080 86101300 9f00: 00000003 83be3100 dfb59fa4 dfb59f18 805bdf78 81498bcc ecac8b10 83be3100 9f20: dfb59f3c dfb59f30 81b6ec00 81b6eacc dfb59f54 dfb59f40 8025b878 8028f548 9f40: dfb59fb0 40000000 dfb59f84 dfb59f58 80221bdc 8025b834 00000000 82a1eb0c 9f60: dfb59fb0 0013ebf0 ecac8b10 80221b30 00000000 ac5484f9 dfb59fac 00000000 9f80: 00000000 00356310 00000036 8020029c 83be3100 00000036 00000000 dfb59fa8 9fa0: 80200060 805bdd40 00000000 00000000 00000003 40946400 20000080 00000000 9fc0: 00000000 00000000 00356310 00000036 003562d8 00000000 00000001 76fcc0dc 9fe0: 76fcbe88 76fcbe78 00018fa0 00130a50 60000010 00000003 00000000 00000000 Call trace: [<814ad7bc>] (subdev_8255_io) from [<814ad4f8>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000000 r6:831d3f00 r5:00000004 r4:814ad7bc [<814ad4a0>] (subdev_8255_do_config) from [<814ad8b0>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<814ad4a0>] (subdev_8255_do_config) from [<814ad8b0>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:863e9000 [<814ad828>] (subdev_8255_io_init) from [<814ada60>] (dev_8255_attach drivers/comedi/drivers/8255.c:84 [inline]) [<814ad828>] (subdev_8255_io_init) from [<814ada60>] (dev_8255_attach+0x74/0x138 drivers/comedi/drivers/8255.c:46) r7:00000000 r6:863e9000 r5:00000000 r4:831d3f00 [<814ad9ec>] (dev_8255_attach) from [<8149c3e8>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r10:82d32f9c r9:00000000 r8:831d3f00 r7:dfb59d90 r6:00000000 r5:831d3f00 r4:82bdac60 [<8149c2e0>] (comedi_device_attach) from [<81497bec>] (do_devconfig_ioctl+0xcc/0x218 drivers/comedi/comedi_fops.c:930) r10:83be3100 r9:00000003 r8:00000001 r7:40946400 r6:b5403587 r5:831d3f00 r4:20000080 [<81497b20>] (do_devconfig_ioctl) from [<81498f14>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000001 r7:40946400 r6:20000080 r5:831d3f00 r4:86101300 [<81498bc0>] (comedi_unlocked_ioctl) from [<805bdf78>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81498bc0>] (comedi_unlocked_ioctl) from [<805bdf78>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81498bc0>] (comedi_unlocked_ioctl) from [<805bdf78>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81498bc0>] (comedi_unlocked_ioctl) from [<805bdf78>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:83be3100 r9:00000003 r8:86101300 r7:20000080 r6:40946400 r5:86101301 r4:00000000 [<805bdd34>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfb59fa8 to 0xdfb59ff0) 9fa0: 00000000 00000000 00000003 40946400 20000080 00000000 9fc0: 00000000 00000000 00356310 00000036 003562d8 00000000 00000001 76fcc0dc 9fe0: 76fcbe88 76fcbe78 00018fa0 00130a50 r10:00000036 r9:83be3100 r8:8020029c r7:00000036 r6:00356310 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