8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f3a when write [fee04f3a] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 4033 Comm: syz.2.17 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 : [<81417944>] lr : [<81417930>] psr: 60000013 sp : dfbe9cb0 ip : dfbe9cb0 fp : dfbe9ccc r10: 00000001 r9 : 00000084 r8 : dfbe9d9c r7 : 00004f37 r6 : 0000009b r5 : 84557480 r4 : 00004f3a r3 : 0000009b r2 : fee04f3a r1 : 00000001 r0 : 84557480 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85c10fc0 DAC: 00000000 Register r0 information: slab kmalloc-192 start 84557480 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 84557480 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 0xdfbe8000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r9 information: non-paged memory Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xdfbe8000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xdfbe8000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Process syz.2.17 (pid: 4033, stack limit = 0xdfbe8000) Stack: (0xdfbe9cb0 to 0xdfbea000) 9ca0: 814178e4 84557480 00004f37 00004f37 9cc0: dfbe9cec dfbe9cd0 8141761c 814178f0 00004f37 80515900 85b2c000 85b2c000 9ce0: dfbe9d0c dfbe9cf0 814179dc 814175d0 84557480 00000000 85b2c000 00004f37 9d00: dfbe9d4c dfbe9d10 81417b88 8141795c 200000c0 84557480 b5403587 00000000 9d20: 84557480 829d46a0 84557480 845574c4 dfbe9d88 84557480 00000000 82b28ad8 9d40: dfbe9d84 dfbe9d50 814066bc 81417b20 845574b0 00000000 dfbe9d74 200000c0 9d60: 84557480 b5403587 845574b0 84e2d400 40946400 00000003 dfbe9e44 dfbe9d88 9d80: 81402014 814065c0 35353238 00000000 00000000 00000000 00000000 00004f37 9da0: 00000005 00000002 00000401 00000001 00000cc7 00000fff 5c95239d 00000005 9dc0: 000003ff 00000802 00001600 00000001 00000001 00000009 0000e1cb 20000006 9de0: 00000004 00000003 00000395 40000005 fffffffd 00000001 fffffff5 ffffeadd 9e00: 00000003 0000003a 00000008 00000004 08000000 dffffffa 00000000 dddcf836 9e20: 00000000 851a1900 84557480 200000c0 845574b0 84e2d400 dfbe9f14 dfbe9e48 9e40: 81403008 81401f20 00000000 00000000 00000000 00000000 00000000 dddcf836 9e60: 00000000 00000000 824a45ec 0000005f 8400d7f8 00000064 845fc00c 84e2d400 9e80: dfbe9ee4 dfbe9e90 807b8b78 807af09c 00000064 00000001 00000000 dfbe9eac 9ea0: 85bf7790 834df908 00006400 0000000b dfbe9ea0 00000000 00000000 dddcf836 9ec0: 851a1900 40946400 200000c0 200000c0 851a1900 00000003 dfbe9ef4 dfbe9ee8 9ee0: 807b8c98 dddcf836 dfbe9f14 40946400 00000000 851a1900 200000c0 851a1900 9f00: 00000003 84e2d400 dfbe9fa4 dfbe9f18 805860e8 81402a58 dfbe9f4c dfbe9f28 9f20: 8034bc54 8034efe4 81ab1b24 81ab19f4 dfbe9f54 dfbe9f40 8025bc80 7e9ba930 9f40: dfbe9fa4 dfbe9f50 8034c4f0 8034bb60 00000000 7e9ba930 ffffffff 80233614 9f60: 00000000 00000000 00000000 00000000 00000000 dddcf836 dfbe9fac 00000000 9f80: 00000000 00326310 00000036 8020029c 84e2d400 00000036 00000000 dfbe9fa8 9fa0: 80200060 80585fc4 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00326310 00000036 00000000 003262e4 0000047d 00000000 9fe0: 7e9ba790 7e9ba780 000192bc 00132360 60000010 00000003 00000000 00000000 Call trace: [<814178e4>] (subdev_8255_io) from [<8141761c>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f37 r6:00004f37 r5:84557480 r4:814178e4 [<814175c4>] (subdev_8255_do_config) from [<814179dc>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<814175c4>] (subdev_8255_do_config) from [<814179dc>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:85b2c000 [<81417950>] (subdev_8255_io_init) from [<81417b88>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<81417950>] (subdev_8255_io_init) from [<81417b88>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00004f37 r6:85b2c000 r5:00000000 r4:84557480 [<81417b14>] (dev_8255_attach) from [<814066bc>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1069) r10:82b28ad8 r9:00000000 r8:84557480 r7:dfbe9d88 r6:845574c4 r5:84557480 r4:829d46a0 [<814065b4>] (comedi_device_attach) from [<81402014>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:928) r10:00000003 r9:40946400 r8:84e2d400 r7:845574b0 r6:b5403587 r5:84557480 r4:200000c0 [<81401f14>] (do_devconfig_ioctl) from [<81403008>] (comedi_unlocked_ioctl+0x5bc/0x1c2c drivers/comedi/comedi_fops.c:2240) r8:84e2d400 r7:845574b0 r6:200000c0 r5:84557480 r4:851a1900 [<81402a4c>] (comedi_unlocked_ioctl) from [<805860e8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81402a4c>] (comedi_unlocked_ioctl) from [<805860e8>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81402a4c>] (comedi_unlocked_ioctl) from [<805860e8>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81402a4c>] (comedi_unlocked_ioctl) from [<805860e8>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:84e2d400 r9:00000003 r8:851a1900 r7:200000c0 r6:851a1900 r5:00000000 r4:40946400 [<80585fb8>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfbe9fa8 to 0xdfbe9ff0) 9fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00326310 00000036 00000000 003262e4 0000047d 00000000 9fe0: 7e9ba790 7e9ba780 000192bc 00132360 r10:00000036 r9:84e2d400 r8:8020029c r7:00000036 r6:00326310 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