comedi comedi1: c6xdigio: I/O port conflict (0xb,3) ================================================================== BUG: KASAN: slab-use-after-free in sysfs_remove_file_ns+0x3d/0x70 fs/sysfs/file.c:510 Read of size 8 at addr ffff88801104e630 by task syz.0.0/5323 CPU: 0 UID: 0 PID: 5323 Comm: syz.0.0 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_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 sysfs_remove_file_ns+0x3d/0x70 fs/sysfs/file.c:510 remove_bind_files drivers/base/bus.c:605 [inline] bus_remove_driver+0x198/0x2f0 drivers/base/bus.c:743 comedi_device_detach_locked+0x178/0x750 drivers/comedi/drivers.c:207 comedi_device_detach drivers/comedi/drivers.c:215 [inline] comedi_device_attach+0x5d4/0x720 drivers/comedi/drivers.c:1011 do_devconfig_ioctl drivers/comedi/comedi_fops.c:872 [inline] comedi_unlocked_ioctl+0x5ff/0x1020 drivers/comedi/comedi_fops.c:2178 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f956c78efc9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f956d637038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f956c9e6090 RCX: 00007f956c78efc9 RDX: 0000200000000100 RSI: 0000000040946400 RDI: 0000000000000004 RBP: 00007f956c811f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f956c9e6128 R14: 00007f956c9e6090 R15: 00007ffd0be0f438 Allocated by task 5322: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417 kasan_kmalloc include/linux/kasan.h:262 [inline] __kmalloc_cache_noprof+0x3d5/0x6f0 mm/slub.c:5755 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] bus_add_driver+0x162/0x640 drivers/base/bus.c:662 driver_register+0x23a/0x320 drivers/base/driver.c:249 c6xdigio_attach+0x94/0x890 drivers/comedi/drivers/c6xdigio.c:253 comedi_device_attach+0x51f/0x720 drivers/comedi/drivers.c:1007 do_devconfig_ioctl drivers/comedi/comedi_fops.c:872 [inline] comedi_unlocked_ioctl+0x5ff/0x1020 drivers/comedi/comedi_fops.c:2178 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5322: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 __kasan_save_free_info+0x46/0x50 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+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2530 [inline] slab_free mm/slub.c:6619 [inline] kfree+0x19a/0x6d0 mm/slub.c:6826 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x22b/0x480 lib/kobject.c:737 bus_remove_driver+0x245/0x2f0 drivers/base/bus.c:749 comedi_device_detach_locked+0x178/0x750 drivers/comedi/drivers.c:207 comedi_device_detach drivers/comedi/drivers.c:215 [inline] comedi_device_attach+0x5d4/0x720 drivers/comedi/drivers.c:1011 do_devconfig_ioctl drivers/comedi/comedi_fops.c:872 [inline] comedi_unlocked_ioctl+0x5ff/0x1020 drivers/comedi/comedi_fops.c:2178 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88801104e600 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 48 bytes inside of freed 256-byte region [ffff88801104e600, ffff88801104e700) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1104e flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801a041b40 dead000000000100 dead000000000122 raw: 0000000000000000 0000000080080008 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5298, tgid 5298 (syz-executor), ts 75303771232, free_ts 75303321968 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1850 prep_new_page mm/page_alloc.c:1858 [inline] get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3884 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5183 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3046 [inline] allocate_slab+0x96/0x3a0 mm/slub.c:3219 new_slab mm/slub.c:3273 [inline] ___slab_alloc+0xe94/0x18a0 mm/slub.c:4643 __slab_alloc+0x65/0x100 mm/slub.c:4762 __slab_alloc_node mm/slub.c:4838 [inline] slab_alloc_node mm/slub.c:5260 [inline] __do_kmalloc_node mm/slub.c:5633 [inline] __kmalloc_node_track_caller_noprof+0x5c7/0x800 mm/slub.c:5743 kmemdup_noprof mm/util.c:138 [inline] kmemdup_noprof include/linux/fortify-string.h:765 [inline] kmemdup_array+0x3f/0x80 mm/util.c:158 ip6t_register_table+0x286/0x7d0 net/ipv6/netfilter/ip6_tables.c:1776 ip6table_filter_table_init+0x75/0xb0 net/ipv6/netfilter/ip6table_filter.c:48 xt_find_table_lock+0x30c/0x3e0 net/netfilter/x_tables.c:1260 xt_request_find_table_lock+0x26/0x100 net/netfilter/x_tables.c:1285 get_info net/ipv6/netfilter/ip6_tables.c:979 [inline] do_ip6t_get_ctl+0x730/0x1180 net/ipv6/netfilter/ip6_tables.c:1668 nf_getsockopt+0x26e/0x290 net/netfilter/nf_sockopt.c:116 ipv6_getsockopt+0x1ed/0x290 net/ipv6/ipv6_sockglue.c:1473 page last free pid 5298 tgid 5298 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2906 ___free_pages_bulk mm/kasan/shadow.c:333 [inline] __kasan_populate_vmalloc mm/kasan/shadow.c:393 [inline] kasan_populate_vmalloc+0x1db/0x270 mm/kasan/shadow.c:435 alloc_vmap_area+0xd7a/0x14c0 mm/vmalloc.c:2098 __get_vm_area_node+0x1f8/0x300 mm/vmalloc.c:3193 __vmalloc_node_range_noprof+0x30c/0x12d0 mm/vmalloc.c:3857 __vmalloc_node_noprof mm/vmalloc.c:3960 [inline] vzalloc_noprof+0xb2/0xf0 mm/vmalloc.c:4034 alloc_counters+0xd3/0x6d0 net/ipv4/netfilter/ip_tables.c:799 copy_entries_to_user net/ipv4/netfilter/ip_tables.c:821 [inline] get_entries net/ipv4/netfilter/ip_tables.c:1022 [inline] do_ipt_get_ctl+0xaac/0x1180 net/ipv4/netfilter/ip_tables.c:1668 nf_getsockopt+0x26e/0x290 net/netfilter/nf_sockopt.c:116 ip_getsockopt+0x1c4/0x220 net/ipv4/ip_sockglue.c:1777 do_sock_getsockopt+0x360/0x650 net/socket.c:2421 __sys_getsockopt net/socket.c:2450 [inline] __do_sys_getsockopt net/socket.c:2457 [inline] __se_sys_getsockopt net/socket.c:2454 [inline] __x64_sys_getsockopt+0x1a5/0x250 net/socket.c:2454 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88801104e500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88801104e580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88801104e600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801104e680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801104e700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================