comedi comedi3: c6xdigio: a I/O base address must be specified ================================================================== BUG: KASAN: slab-use-after-free in sysfs_remove_file_ns+0x63/0x70 fs/sysfs/file.c:510 Read of size 8 at addr ffff88806aa5b830 by task syz.2.4561/20157 CPU: 3 UID: 0 PID: 20157 Comm: syz.2.4561 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 sysfs_remove_file_ns+0x63/0x70 fs/sysfs/file.c:510 sysfs_remove_file include/linux/sysfs.h:770 [inline] driver_remove_file drivers/base/driver.c:201 [inline] driver_remove_file+0x4a/0x60 drivers/base/driver.c:197 remove_bind_files drivers/base/bus.c:605 [inline] bus_remove_driver+0x224/0x2c0 drivers/base/bus.c:743 driver_unregister+0x76/0xb0 drivers/base/driver.c:277 comedi_device_detach_locked+0x12f/0xa50 drivers/comedi/drivers.c:207 comedi_device_detach+0x67/0xb0 drivers/comedi/drivers.c:215 comedi_device_attach+0x43d/0x900 drivers/comedi/drivers.c:1011 do_devconfig_ioctl+0x1b1/0x710 drivers/comedi/comedi_fops.c:872 comedi_unlocked_ioctl+0x165d/0x2ee0 drivers/comedi/comedi_fops.c:2178 comedi_compat_ioctl+0x1d0/0x960 drivers/comedi/comedi_fops.c:3249 __do_compat_sys_ioctl fs/ioctl.c:695 [inline] __se_compat_sys_ioctl fs/ioctl.c:638 [inline] __ia32_compat_sys_ioctl+0x242/0x370 fs/ioctl.c:638 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x7c/0x370 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7fe3579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f54d655c EFLAGS: 00000296 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000040946400 RDX: 0000000080000080 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 20097: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:417 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5650 [inline] __kmalloc_noprof+0x32f/0x870 mm/slub.c:5662 kmalloc_noprof include/linux/slab.h:961 [inline] kmalloc_array_noprof include/linux/slab.h:1003 [inline] iter_file_splice_write+0x1cc/0x12b0 fs/splice.c:679 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x192/0x6c0 fs/splice.c:1161 splice_direct_to_actor+0x345/0xa30 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x174/0x240 fs/splice.c:1230 do_sendfile+0xb06/0xe50 fs/read_write.c:1370 __do_compat_sys_sendfile fs/read_write.c:1446 [inline] __se_compat_sys_sendfile fs/read_write.c:1435 [inline] __ia32_compat_sys_sendfile+0x162/0x220 fs/read_write.c:1435 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x7c/0x370 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Freed by task 20097: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 __kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2543 [inline] slab_free mm/slub.c:6642 [inline] kfree+0x29e/0x710 mm/slub.c:6849 iter_file_splice_write+0x67a/0x12b0 fs/splice.c:770 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x192/0x6c0 fs/splice.c:1161 splice_direct_to_actor+0x345/0xa30 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x174/0x240 fs/splice.c:1230 do_sendfile+0xb06/0xe50 fs/read_write.c:1370 __do_compat_sys_sendfile fs/read_write.c:1446 [inline] __se_compat_sys_sendfile fs/read_write.c:1435 [inline] __ia32_compat_sys_sendfile+0x162/0x220 fs/read_write.c:1435 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x7c/0x370 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e The buggy address belongs to the object at ffff88806aa5b800 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 48 bytes inside of freed 256-byte region [ffff88806aa5b800, ffff88806aa5b900) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88806aa5b800 pfn:0x6aa5a head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x4fff00000000240(workingset|head|node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000240 ffff88801b442b40 ffffea00013e3e10 ffffea000136a210 raw: ffff88806aa5b800 000000000010000f 00000000f5000000 0000000000000000 head: 04fff00000000240 ffff88801b442b40 ffffea00013e3e10 ffffea000136a210 head: ffff88806aa5b800 000000000010000f 00000000f5000000 0000000000000000 head: 04fff00000000001 ffffea0001aa9681 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 12985, tgid 12980 (syz.0.2174), ts 420717686621, free_ts 411545829929 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1845 prep_new_page mm/page_alloc.c:1853 [inline] get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3879 __alloc_frozen_pages_noprof+0x25f/0x2440 mm/page_alloc.c:5178 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3059 [inline] allocate_slab mm/slub.c:3232 [inline] new_slab+0x24a/0x360 mm/slub.c:3286 ___slab_alloc+0xee7/0x1cd0 mm/slub.c:4655 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4778 __slab_alloc_node mm/slub.c:4854 [inline] slab_alloc_node mm/slub.c:5276 [inline] __do_kmalloc_node mm/slub.c:5649 [inline] __kmalloc_noprof+0x501/0x870 mm/slub.c:5662 kmalloc_noprof include/linux/slab.h:961 [inline] kmalloc_array_noprof include/linux/slab.h:1003 [inline] iter_file_splice_write+0x1cc/0x12b0 fs/splice.c:679 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x192/0x6c0 fs/splice.c:1161 splice_direct_to_actor+0x345/0xa30 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x174/0x240 fs/splice.c:1230 do_sendfile+0xb06/0xe50 fs/read_write.c:1370 __do_compat_sys_sendfile fs/read_write.c:1446 [inline] __se_compat_sys_sendfile fs/read_write.c:1435 [inline] __ia32_compat_sys_sendfile+0x162/0x220 fs/read_write.c:1435 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x7c/0x370 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331 page last free pid 9837 tgid 9837 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_pages_ok+0x725/0xf80 mm/page_alloc.c:1570 batadv_hash_destroy+0x31/0x70 net/batman-adv/hash.c:33 batadv_originator_free+0x2df/0x380 net/batman-adv/originator.c:926 batadv_mesh_free+0xa1/0x170 net/batman-adv/main.c:272 batadv_meshif_free+0x15/0x20 net/batman-adv/mesh-interface.c:989 netdev_run_todo+0x780/0x12a0 net/core/dev.c:11594 default_device_exit_batch+0x99a/0xc80 net/core/dev.c:12852 ops_exit_list net/core/net_namespace.c:205 [inline] ops_undo_list+0x363/0xab0 net/core/net_namespace.c:252 cleanup_net+0x41b/0x830 net/core/net_namespace.c:695 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x855/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff88806aa5b700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88806aa5b780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88806aa5b800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88806aa5b880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806aa5b900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi