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: 1 UID: 0 PID: 6131 Comm: syz.2.459 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 : [<813b8ba0>] lr : [<813b8b8c>] psr: 60000013 sp : dfa21cb8 ip : dfa21cb8 fp : dfa21cd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 840caa80 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 840caa80 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 849b4080 DAC: 00000000 Register r0 information: slab kmalloc-192 start 840caa80 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 840caa80 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 0xdfa20000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r12 information: 2-page vmalloc region starting at 0xdfa20000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Process syz.2.459 (pid: 6131, stack limit = 0xdfa20000) Stack: (0xdfa21cb8 to 0xdfa22000) 1ca0: 813b8b40 840caa80 1cc0: 00004f27 00004f27 dfa21cf4 dfa21cd8 813b8878 813b8b4c 00004f27 dfa21cf8 1ce0: 813b8c38 841b7000 dfa21d14 dfa21cf8 813b8c38 813b882c 841b7000 840caa80 1d00: dfa21da4 00004f27 dfa21d54 dfa21d18 813b8e2c 813b8bb8 82ae3da0 83860000 1d20: 828215b0 00000000 00000000 829d0144 840caa80 840caac4 dfa21d90 840caa80 1d40: 00000000 82b16f40 dfa21d8c dfa21d58 813a7d34 813b8d7c 200000c0 00000000 1d60: dfa21d7c 200000c0 840caa80 b5403587 200000c0 83b0a400 40946400 00000003 1d80: dfa21e4c dfa21d90 813a3880 813a7c38 35353238 00000000 00000000 00000000 1da0: 00000000 00004f27 00000005 00000002 00000401 fffffffd 00000cc7 00000ff7 1dc0: 5c95239c 00000001 000003ff 00000006 00001600 00000001 00000001 00000009 1de0: 0000e1cb 00000006 00000004 00000010 00000395 8000008b fffffffe 0000000b 1e00: fffffffe ffffeadb 00000000 0000003c 00000000 00000004 00000002 dffffffa 1e20: 00000000 50cb92ff 00000000 855aa3c0 840caa80 200000c0 200000c0 83b0a400 1e40: dfa21f14 dfa21e50 813a484c 813a378c 00000000 00000000 00000000 50cb92ff 1e60: 00000000 00000000 8247054c 0000005f 83f27658 840caab0 84108684 83b0a400 1e80: dfa21ee4 dfa21e90 80797aa4 8078de08 00000064 00000001 00000000 dfa21eac 1ea0: 84bb9f10 8341e6e8 00006400 0000000b dfa21ea0 00000000 00000000 50cb92ff 1ec0: 855aa3c0 40946400 200000c0 200000c0 855aa3c0 00000003 dfa21ef4 dfa21ee8 1ee0: 80797bc4 50cb92ff dfa21f14 40946400 00000000 855aa3c1 200000c0 855aa3c0 1f00: 00000003 83b0a400 dfa21fa4 dfa21f18 8056cdc8 813a427c ecac8b10 83b0a400 1f20: dfa21f3c dfa21f30 81a39db8 81a39c88 dfa21f54 dfa21f40 8025e490 8028ef6c 1f40: dfa21fb0 40000000 dfa21f84 dfa21f58 802229ec 8025e44c 00000000 8281cddc 1f60: dfa21fb0 0014c820 ecac8b10 80222940 00000000 50cb92ff dfa21fac 00000000 1f80: 00000000 002f6308 00000036 8020029c 83b0a400 00000036 00000000 dfa21fa8 1fa0: 80200060 8056cca4 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76f760bc 1fe0: 76f75ec0 76f75eb0 0001948c 001322c0 60000010 00000003 00000000 00000000 Call trace: [<813b8b40>] (subdev_8255_io) from [<813b8878>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:840caa80 r4:813b8b40 [<813b8820>] (subdev_8255_do_config) from [<813b8c38>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813b8820>] (subdev_8255_do_config) from [<813b8c38>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:841b7000 [<813b8bac>] (subdev_8255_io_init) from [<813b8e2c>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813b8bac>] (subdev_8255_io_init) from [<813b8e2c>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:dfa21da4 r5:840caa80 r4:841b7000 [<813b8d70>] (dev_8255_attach) from [<813a7d34>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b16f40 r9:00000000 r8:840caa80 r7:dfa21d90 r6:840caac4 r5:840caa80 r4:829d0144 [<813a7c2c>] (comedi_device_attach) from [<813a3880>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:83b0a400 r7:200000c0 r6:b5403587 r5:840caa80 r4:200000c0 [<813a3780>] (do_devconfig_ioctl) from [<813a484c>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:83b0a400 r7:200000c0 r6:200000c0 r5:840caa80 r4:855aa3c0 [<813a4270>] (comedi_unlocked_ioctl) from [<8056cdc8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813a4270>] (comedi_unlocked_ioctl) from [<8056cdc8>] (do_vfs_ioctl fs/ioctl.c:552 [inline]) [<813a4270>] (comedi_unlocked_ioctl) from [<8056cdc8>] (__do_sys_ioctl fs/ioctl.c:596 [inline]) [<813a4270>] (comedi_unlocked_ioctl) from [<8056cdc8>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:584) r10:83b0a400 r9:00000003 r8:855aa3c0 r7:200000c0 r6:855aa3c1 r5:00000000 r4:40946400 [<8056cc98>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfa21fa8 to 0xdfa21ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76f760bc 1fe0: 76f75ec0 76f75eb0 0001948c 001322c0 r10:00000036 r9:83b0a400 r8:8020029c r7:00000036 r6:002f6308 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