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: 5801 Comm: syz.2.526 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 : [<81441370>] lr : [<8144135c>] psr: 60000013 sp : eb289cb8 ip : eb289cb8 fp : eb289cd4 r10: 00000000 r9 : 00000084 r8 : eb289da4 r7 : 00004f27 r6 : 0000009b r5 : 8337e480 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 8337e480 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 84c8e1c0 DAC: 00000000 Register r0 information: slab kmalloc-192 start 8337e480 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 8337e480 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 0xeb288000 allocated at kernel_clone+0xac/0x42c kernel/fork.c:2653 Register r9 information: non-paged memory Register r10 information: NULL pointer Register r11 information: 2-page vmalloc region starting at 0xeb288000 allocated at kernel_clone+0xac/0x42c kernel/fork.c:2653 Register r12 information: 2-page vmalloc region starting at 0xeb288000 allocated at kernel_clone+0xac/0x42c kernel/fork.c:2653 Process syz.2.526 (pid: 5801, stack limit = 0xeb288000) Stack: (0xeb289cb8 to 0xeb28a000) 9ca0: 81441310 00004f27 9cc0: 8337e480 00004f27 eb289cf4 eb289cd8 8144104c 8144131c 00004f27 805239fc 9ce0: 85ae1000 85ae1000 eb289d14 eb289cf8 81441404 81441000 8337e480 00000000 9d00: 85ae1000 00004f27 eb289d54 eb289d18 814415b4 81441388 82afc4e4 83907100 9d20: 82821800 00000000 00000000 829d6f20 8337e480 00000000 eb289d90 8337e480 9d40: 00000000 82b2f06c eb289d8c eb289d58 8142fefc 8144154c 40946400 00000000 9d60: eb289d7c 200000c0 8337e480 b5403587 40946400 00000003 00000003 846ba4c0 9d80: eb289e4c eb289d90 8142b708 8142fdfc 35353238 00000000 00000000 00000000 9da0: 00000000 00004f27 00000005 00000004 00000401 00000001 00000cc7 00000401 9dc0: 5c952399 00000401 000003ff 00000002 00000300 00000001 fffffffa 00000006 9de0: 0000e1cc 00000000 e0000000 00000003 000001ff 80000089 fffffffd 00000007 9e00: 00000004 ffffeadb ffffffff 0000003d 00000008 00000008 000007ff dffffffa 9e20: 00000000 6eaefb03 00000000 85a37780 8337e480 200000c0 40946400 00000003 9e40: eb289f14 eb289e50 8142ca2c 8142b640 00000000 6eaefb03 00000000 00000000 9e60: 824b957c eb289ea4 0000005f 842997f8 00000064 8337e4b0 eb289ee4 eb289e88 9e80: 807cf790 807c5b68 00000064 00000001 00000000 eb289ea4 86301910 8342a440 9ea0: 00006400 0000000b eb289e98 00000000 00000000 6eaefb03 00000000 85a37780 9ec0: 40946400 200000c0 200000c0 85a37780 00000003 846ba4c0 eb289ef4 eb289ee8 9ee0: 807cf8c0 6eaefb03 eb289f14 00000000 85a37781 40946400 200000c0 85a37780 9f00: 00000003 846ba4c0 eb289fa4 eb289f18 80590c2c 8142c6e4 ecac8b10 846ba4c0 9f20: eb289f3c eb289f30 81ae53d4 81ae52a0 eb289f54 eb289f40 8025a87c 8028c380 9f40: eb289fb0 40000000 eb289f84 eb289f58 80220bf8 8025a838 00000000 8281d2fc 9f60: eb289fb0 0013e480 ecac8b10 80220b4c 00000000 6eaefb03 eb289fac 00000000 9f80: 00000000 00346310 00000036 8020029c 846ba4c0 00000036 00000000 eb289fa8 9fa0: 80200060 805909f4 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f880dc 9fe0: 76f87e88 76f87e78 00018ba0 001302e0 60000010 00000003 00000000 00000000 Call trace: [<81441310>] (subdev_8255_io) from [<8144104c>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:8337e480 r5:00004f27 r4:81441310 [<81440ff4>] (subdev_8255_do_config) from [<81441404>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<81440ff4>] (subdev_8255_do_config) from [<81441404>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:85ae1000 [<8144137c>] (subdev_8255_io_init) from [<814415b4>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<8144137c>] (subdev_8255_io_init) from [<814415b4>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:85ae1000 r5:00000000 r4:8337e480 [<81441540>] (dev_8255_attach) from [<8142fefc>] (comedi_device_attach+0x10c/0x248 drivers/comedi/drivers.c:1069) r10:82b2f06c r9:00000000 r8:8337e480 r7:eb289d90 r6:00000000 r5:8337e480 r4:829d6f20 [<8142fdf0>] (comedi_device_attach) from [<8142b708>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:928) r10:846ba4c0 r9:00000003 r8:00000003 r7:40946400 r6:b5403587 r5:8337e480 r4:200000c0 [<8142b634>] (do_devconfig_ioctl) from [<8142ca2c>] (comedi_unlocked_ioctl+0x354/0x1dbc drivers/comedi/comedi_fops.c:2300) r8:00000003 r7:40946400 r6:200000c0 r5:8337e480 r4:85a37780 [<8142c6d8>] (comedi_unlocked_ioctl) from [<80590c2c>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<8142c6d8>] (comedi_unlocked_ioctl) from [<80590c2c>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<8142c6d8>] (comedi_unlocked_ioctl) from [<80590c2c>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<8142c6d8>] (comedi_unlocked_ioctl) from [<80590c2c>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:846ba4c0 r9:00000003 r8:85a37780 r7:200000c0 r6:40946400 r5:85a37781 r4:00000000 [<805909e8>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xeb289fa8 to 0xeb289ff0) 9fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f880dc 9fe0: 76f87e88 76f87e78 00018ba0 001302e0 r10:00000036 r9:846ba4c0 r8:8020029c r7:00000036 r6:00346310 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