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: 5025 Comm: syz.1.344 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 : [<813db8d0>] lr : [<813db8bc>] psr: 60000013 sp : dfa11cb8 ip : dfa11cb8 fp : dfa11cd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 84123d80 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 84123d80 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 8573d340 DAC: 00000000 Register r0 information: slab kmalloc-192 start 84123d80 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 84123d80 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 0xdfa10000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdfa10000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.1.344 (pid: 5025, stack limit = 0xdfa10000) Stack: (0xdfa11cb8 to 0xdfa12000) 1ca0: 813db870 84123d80 1cc0: 00004f27 00004f27 dfa11cf4 dfa11cd8 813db5a8 813db87c 00004f27 8050a8a4 1ce0: 84a3a800 84a3a800 dfa11d14 dfa11cf8 813db968 813db55c 84a3a800 84123d80 1d00: dfa11da4 00004f27 dfa11d54 dfa11d18 813dbb5c 813db8e8 82af1fe0 862fca00 1d20: 828215f0 00000000 00000000 829d23cc 84123d80 84123dc4 dfa11d90 84123d80 1d40: 00000000 82b25910 dfa11d8c dfa11d58 813caa54 813dbaac 200000c0 00000000 1d60: dfa11d7c 200000c0 84123d80 b5403587 200000c0 85856000 40946400 00000003 1d80: dfa11e4c dfa11d90 813c65a0 813ca958 35353238 00000000 00000000 00000000 1da0: 00000000 00004f27 00000005 00000002 00000401 00000001 00000cc7 00000fff 1dc0: 5c952399 00000005 000003ff 00000802 00001600 00000001 00000000 00000009 1de0: 0000e1cb 00000006 00000004 00000003 00000395 80000089 fffffffd 00000000 1e00: 00000006 ffffeadb 00000003 0001003c 00000008 00000004 08000000 00000005 1e20: 00000000 960edc1e 00000000 85a6d780 84123d80 200000c0 200000c0 85856000 1e40: dfa11f14 dfa11e50 813c756c 813c64ac 00000000 00000000 00000000 960edc1e 1e60: 00000000 00000000 824625b4 0000005f 842ad408 84123db0 840b7c6c 85856000 1e80: dfa11ee4 dfa11e90 807a7c94 8079e08c 00000064 00000001 00000000 dfa11eac 1ea0: 8585fe50 8342b330 00006400 0000000b dfa11ea0 00000000 00000000 960edc1e 1ec0: 85a6d780 40946400 200000c0 200000c0 85a6d780 00000003 dfa11ef4 dfa11ee8 1ee0: 807a7db4 960edc1e dfa11f14 40946400 00000000 85a6d781 200000c0 85a6d780 1f00: 00000003 85856000 dfa11fa4 dfa11f18 80578eb8 813c6f9c ecac8b10 85856000 1f20: dfa11f3c dfa11f30 81a61000 81a60ed0 dfa11f54 dfa11f40 8025c484 8028d914 1f40: dfa11fb0 40000000 dfa11f84 dfa11f58 802229ec 8025c440 00000000 8281cfb4 1f60: dfa11fb0 0014ced0 ecac8b10 80222940 00000000 960edc1e dfa11fac 00000000 1f80: 00000000 00316308 00000036 8020029c 85856000 00000036 00000000 dfa11fa8 1fa0: 80200060 80578d94 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fb80bc 1fe0: 76fb7ec0 76fb7eb0 00019294 00132970 60000010 00000003 00000000 00000000 Call trace: [<813db870>] (subdev_8255_io) from [<813db5a8>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:84123d80 r4:813db870 [<813db550>] (subdev_8255_do_config) from [<813db968>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813db550>] (subdev_8255_do_config) from [<813db968>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:84a3a800 [<813db8dc>] (subdev_8255_io_init) from [<813dbb5c>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813db8dc>] (subdev_8255_io_init) from [<813dbb5c>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:dfa11da4 r5:84123d80 r4:84a3a800 [<813dbaa0>] (dev_8255_attach) from [<813caa54>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:84123d80 r7:dfa11d90 r6:84123dc4 r5:84123d80 r4:829d23cc [<813ca94c>] (comedi_device_attach) from [<813c65a0>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:85856000 r7:200000c0 r6:b5403587 r5:84123d80 r4:200000c0 [<813c64a0>] (do_devconfig_ioctl) from [<813c756c>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:85856000 r7:200000c0 r6:200000c0 r5:84123d80 r4:85a6d780 [<813c6f90>] (comedi_unlocked_ioctl) from [<80578eb8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c6f90>] (comedi_unlocked_ioctl) from [<80578eb8>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c6f90>] (comedi_unlocked_ioctl) from [<80578eb8>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c6f90>] (comedi_unlocked_ioctl) from [<80578eb8>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:85856000 r9:00000003 r8:85a6d780 r7:200000c0 r6:85a6d781 r5:00000000 r4:40946400 [<80578d88>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfa11fa8 to 0xdfa11ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fb80bc 1fe0: 76fb7ec0 76fb7eb0 00019294 00132970 r10:00000036 r9:85856000 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