8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f2a when write [fee04f2a] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 5834 Comm: syz.1.568 Not tainted syzkaller #0 PREEMPT 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 : [<813db9c0>] lr : [<813db9ac>] psr: 60000013 sp : df9c9cb8 ip : df9c9cb8 fp : df9c9cd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 8416fd80 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 8416fd80 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 8487a780 DAC: fffffffd Register r0 information: slab kmalloc-192 start 8416fd80 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 8416fd80 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: non-paged memory Register r8 information: non-paged memory Register r9 information: NULL pointer Register r10 information: NULL pointer Register r11 information: 2-page vmalloc region starting at 0xdf9c8000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdf9c8000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.1.568 (pid: 5834, stack limit = 0xdf9c8000) Stack: (0xdf9c9cb8 to 0xdf9ca000) 9ca0: 813db960 8416fd80 9cc0: 00004f27 00004f27 df9c9cf4 df9c9cd8 813db698 813db96c 00004f27 8050a8b4 9ce0: 84214000 84214000 df9c9d14 df9c9cf8 813dba58 813db64c 84214000 8416fd80 9d00: df9c9da4 00004f27 df9c9d54 df9c9d18 813dbc4c 813db9d8 82af1fe0 83866c00 9d20: 828215f0 00000000 00000000 829d23cc 8416fd80 8416fdc4 df9c9d90 8416fd80 9d40: 00000000 82b25910 df9c9d8c df9c9d58 813cab44 813dbb9c 200000c0 00000000 9d60: df9c9d7c 200000c0 8416fd80 b5403587 200000c0 8520bc00 40946400 00000003 9d80: df9c9e4c df9c9d90 813c6690 813caa48 35353238 00000000 00000000 00000000 9da0: 00000000 00004f27 00000005 00000002 00000401 00000001 00000cc8 00000fff 9dc0: 5c952399 00000005 000003ff 00000802 00001600 00000000 00000001 00000009 9de0: 0000e1cb 00000008 000000d4 00000003 00000000 00000000 0100d5f2 00000020 9e00: f7fffff5 ffffeadb ffffffff 00000002 00000008 00000004 08000000 00000009 9e20: 00000000 7901ef05 00000000 85f939c0 8416fd80 200000c0 200000c0 8520bc00 9e40: df9c9f14 df9c9e50 813c765c 813c659c 00000000 00000000 00000000 7901ef05 9e60: 00000000 00000000 824625b4 0000005f 83dfd600 8416fdb0 8427a48c 8520bc00 9e80: df9c9ee4 df9c9e90 807a7ca4 8079e09c 00000064 00000001 00000000 df9c9eac 9ea0: 848916d0 83428dd0 00006400 0000000b df9c9ea0 00000000 00000000 7901ef05 9ec0: 85f939c0 40946400 200000c0 200000c0 85f939c0 00000003 df9c9ef4 df9c9ee8 9ee0: 807a7dc4 7901ef05 df9c9f14 40946400 00000000 85f939c1 200000c0 85f939c0 9f00: 00000003 8520bc00 df9c9fa4 df9c9f18 80578ec8 813c708c ecac8b10 8520bc00 9f20: df9c9f3c df9c9f30 81a611a0 81a61070 df9c9f54 df9c9f40 8025c484 8028d914 9f40: df9c9fb0 40000000 df9c9f84 df9c9f58 802229ec 8025c440 00000000 8281cfb4 9f60: df9c9fb0 0014ced0 ecac8b10 80222940 00000000 7901ef05 df9c9fac 00000000 9f80: 00000000 00316308 00000036 8020029c 8520bc00 00000036 00000000 df9c9fa8 9fa0: 80200060 80578da4 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fcb0bc 9fe0: 76fcaec0 76fcaeb0 00019294 00132970 60000010 00000003 00000000 00000000 Call trace: [<813db960>] (subdev_8255_io) from [<813db698>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:8416fd80 r4:813db960 [<813db640>] (subdev_8255_do_config) from [<813dba58>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813db640>] (subdev_8255_do_config) from [<813dba58>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:84214000 [<813db9cc>] (subdev_8255_io_init) from [<813dbc4c>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813db9cc>] (subdev_8255_io_init) from [<813dbc4c>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:df9c9da4 r5:8416fd80 r4:84214000 [<813dbb90>] (dev_8255_attach) from [<813cab44>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:8416fd80 r7:df9c9d90 r6:8416fdc4 r5:8416fd80 r4:829d23cc [<813caa3c>] (comedi_device_attach) from [<813c6690>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:8520bc00 r7:200000c0 r6:b5403587 r5:8416fd80 r4:200000c0 [<813c6590>] (do_devconfig_ioctl) from [<813c765c>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:8520bc00 r7:200000c0 r6:200000c0 r5:8416fd80 r4:85f939c0 [<813c7080>] (comedi_unlocked_ioctl) from [<80578ec8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c7080>] (comedi_unlocked_ioctl) from [<80578ec8>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c7080>] (comedi_unlocked_ioctl) from [<80578ec8>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c7080>] (comedi_unlocked_ioctl) from [<80578ec8>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:8520bc00 r9:00000003 r8:85f939c0 r7:200000c0 r6:85f939c1 r5:00000000 r4:40946400 [<80578d98>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf9c9fa8 to 0xdf9c9ff0) 9fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fcb0bc 9fe0: 76fcaec0 76fcaeb0 00019294 00132970 r10:00000036 r9:8520bc00 r8:8020029c r7:00000036 r6:00316308 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