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: 4453 Comm: syz.1.199 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 : [<813db898>] lr : [<813db884>] psr: 60000013 sp : dfb59cb8 ip : dfb59cb8 fp : dfb59cd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 84085540 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 84085540 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 84da6400 DAC: fffffffd Register r0 information: slab kmalloc-192 start 84085540 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 84085540 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 0xdfb58000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdfb58000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.1.199 (pid: 4453, stack limit = 0xdfb58000) Stack: (0xdfb59cb8 to 0xdfb5a000) 9ca0: 813db838 84085540 9cc0: 00004f27 00004f27 dfb59cf4 dfb59cd8 813db570 813db844 00004f27 8050a88c 9ce0: 84d80000 84d80000 dfb59d14 dfb59cf8 813db930 813db524 84d80000 84085540 9d00: dfb59da4 00004f27 dfb59d54 dfb59d18 813dbb24 813db8b0 82af1fe0 83a9ba00 9d20: 828215f0 00000000 00000000 829d23cc 84085540 84085584 dfb59d90 84085540 9d40: 00000000 82b25910 dfb59d8c dfb59d58 813caa20 813dba74 200000c0 00000000 9d60: dfb59d7c 200000c0 84085540 b5403587 200000c0 8575a400 40946400 00000003 9d80: dfb59e4c dfb59d90 813c656c 813ca924 35353238 00000000 00000000 00000000 9da0: 00000000 00004f27 00000005 00000002 000003fd 00000001 00000cc7 00000fff 9dc0: 5c952399 00010005 000003ff 00000802 00001600 00000001 00000001 00000009 9de0: 0000e1cb 00000009 00000004 08000007 00000395 80000089 fffffffd 00000000 9e00: 00000004 ffffeadb 00000003 0000003c 00000008 00000002 08000000 dffffffa 9e20: 00000000 006eafb7 00000000 85ae6180 84085540 200000c0 200000c0 8575a400 9e40: dfb59f14 dfb59e50 813c7538 813c6478 00000000 00000000 00000000 006eafb7 9e60: 00000000 00000000 824625b4 0000005f 84202058 84085570 83a9ed44 8575a400 9e80: dfb59ee4 dfb59e90 807a7cbc 8079e0b4 00000064 00000001 00000000 dfb59eac 9ea0: 85a4acd0 834ebcc0 00006400 0000000b dfb59ea0 00000000 00000000 006eafb7 9ec0: 85ae6180 40946400 200000c0 200000c0 85ae6180 00000007 dfb59ef4 dfb59ee8 9ee0: 807a7ddc 006eafb7 dfb59f14 40946400 00000000 85ae6181 200000c0 85ae6180 9f00: 00000007 8575a400 dfb59fa4 dfb59f18 80578ee0 813c6f68 ecac8b10 8575a400 9f20: dfb59f3c dfb59f30 81a60dc0 81a60c90 dfb59f54 dfb59f40 8025c484 8028d914 9f40: dfb59fb0 40000000 dfb59f84 dfb59f58 802229ec 8025c440 00000000 8281cfb4 9f60: dfb59fb0 0014ced0 ecac8b10 80222940 00000000 006eafb7 dfb59fac 00000000 9f80: 00000000 003163a8 00000036 8020029c 8575a400 00000036 00000000 dfb59fa8 9fa0: 80200060 80578dbc 00000000 00000000 00000007 40946400 200000c0 00000000 9fc0: 00000000 00000000 003163a8 00000036 00300000 00000000 00006364 76f840bc 9fe0: 76f83ec0 76f83eb0 0001928c 00132970 60000010 00000007 00000000 00000000 Call trace: [<813db838>] (subdev_8255_io) from [<813db570>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:84085540 r4:813db838 [<813db518>] (subdev_8255_do_config) from [<813db930>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813db518>] (subdev_8255_do_config) from [<813db930>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:84d80000 [<813db8a4>] (subdev_8255_io_init) from [<813dbb24>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813db8a4>] (subdev_8255_io_init) from [<813dbb24>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:dfb59da4 r5:84085540 r4:84d80000 [<813dba68>] (dev_8255_attach) from [<813caa20>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:84085540 r7:dfb59d90 r6:84085584 r5:84085540 r4:829d23cc [<813ca918>] (comedi_device_attach) from [<813c656c>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:8575a400 r7:200000c0 r6:b5403587 r5:84085540 r4:200000c0 [<813c646c>] (do_devconfig_ioctl) from [<813c7538>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:8575a400 r7:200000c0 r6:200000c0 r5:84085540 r4:85ae6180 [<813c6f5c>] (comedi_unlocked_ioctl) from [<80578ee0>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c6f5c>] (comedi_unlocked_ioctl) from [<80578ee0>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c6f5c>] (comedi_unlocked_ioctl) from [<80578ee0>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c6f5c>] (comedi_unlocked_ioctl) from [<80578ee0>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:8575a400 r9:00000007 r8:85ae6180 r7:200000c0 r6:85ae6181 r5:00000000 r4:40946400 [<80578db0>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfb59fa8 to 0xdfb59ff0) 9fa0: 00000000 00000000 00000007 40946400 200000c0 00000000 9fc0: 00000000 00000000 003163a8 00000036 00300000 00000000 00006364 76f840bc 9fe0: 76f83ec0 76f83eb0 0001928c 00132970 r10:00000036 r9:8575a400 r8:8020029c r7:00000036 r6:003163a8 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