IPv6: ADDRCONF(NETDEV_UP): wlan1: link is not ready wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready ================================================================== BUG: KASAN: use-after-free in snd_mixer_oss_get_volume1+0x4ba/0x570 sound/core/oss/mixer_oss.c:608 Read of size 4 at addr ffff8800a482f604 by task syz-executor.5/10061 CPU: 0 PID: 10061 Comm: syz-executor.5 Not tainted 4.18.0-syzkaller #0 IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x15a/0x20d lib/dump_stack.c:113 print_address_description.cold.6+0x9/0x244 mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report mm/kasan/report.c:412 [inline] kasan_report.cold.7+0x242/0x305 mm/kasan/report.c:396 wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432 snd_mixer_oss_get_volume1+0x4ba/0x570 sound/core/oss/mixer_oss.c:608 snd_mixer_oss_get_volume sound/core/oss/mixer_oss.c:272 [inline] snd_mixer_oss_ioctl1+0x1eb/0x1610 sound/core/oss/mixer_oss.c:372 snd_mixer_oss_ioctl_compat+0x38/0x60 sound/core/oss/mixer_oss.c:405 __do_compat_sys_ioctl fs/compat_ioctl.c:1459 [inline] __se_compat_sys_ioctl+0x7bd/0x2610 fs/compat_ioctl.c:1405 __ia32_compat_sys_ioctl+0x6b/0xa0 fs/compat_ioctl.c:1405 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline] do_fast_syscall_32+0x23f/0xad4 arch/x86/entry/common.c:397 wlan0: Creating new IBSS network, BSSID 50:50:50:50:50:50 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready RIP: 0023:0xf7045c89 IPv6: ADDRCONF(NETDEV_UP): wlan1: link is not ready Code: 85 wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 d2 wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 0c 24 c3 8b 1c 24 c3 90 90 90 90 90 90 90 90 90 90 90 90 51 52 55 IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready 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:00000000f67055fc EFLAGS: 00000296 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000080254d18 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 10051: save_stack mm/kasan/kasan.c:448 [inline] set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc.part.1+0x62/0xf0 mm/kasan/kasan.c:553 kasan_kmalloc+0xaf/0xc0 mm/kasan/kasan.c:538 kmem_cache_alloc_trace+0x142/0x350 mm/slub.c:2735 IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready kmalloc include/linux/slab.h:513 [inline] snd_mixer_oss_build_input+0x56f/0xc40 sound/core/oss/mixer_oss.c:1092 snd_mixer_oss_proc_write+0x30c/0x4a0 sound/core/oss/mixer_oss.c:1232 snd_info_text_entry_release+0xe3/0x240 sound/core/info.c:425 close_pdeo.part.0+0xd8/0x2e0 fs/proc/inode.c:174 close_pdeo+0xf6/0x150 fs/proc/inode.c:166 proc_reg_release+0xff/0x170 fs/proc/inode.c:393 wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 __fput+0x232/0x780 fs/file_table.c:209 ____fput+0x9/0x10 fs/file_table.c:243 task_work_run+0x111/0x180 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:192 [inline] exit_to_usermode_loop+0x180/0x1e0 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_32_irqs_on arch/x86/entry/common.c:341 [inline] do_fast_syscall_32+0x8cb/0xad4 arch/x86/entry/common.c:397 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 Freed by task 10049: save_stack mm/kasan/kasan.c:448 [inline] set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x167/0x240 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 wlan0: Creating new IBSS network, BSSID 50:50:50:50:50:50 slab_free_hook mm/slub.c:1373 [inline] slab_free_freelist_hook mm/slub.c:1400 [inline] slab_free mm/slub.c:2955 [inline] kfree+0x130/0x3b0 mm/slub.c:3908 snd_mixer_oss_slot_free+0xcf/0x110 sound/core/oss/mixer_oss.c:955 mixer_slot_clear+0x53/0xa0 sound/core/oss/mixer_oss.c:963 snd_mixer_oss_build_input+0x702/0xc40 sound/core/oss/mixer_oss.c:1100 snd_mixer_oss_proc_write+0x30c/0x4a0 sound/core/oss/mixer_oss.c:1232 snd_info_text_entry_release+0xe3/0x240 sound/core/info.c:425 close_pdeo.part.0+0xd8/0x2e0 fs/proc/inode.c:174 close_pdeo+0xf6/0x150 fs/proc/inode.c:166 proc_reg_release+0xff/0x170 fs/proc/inode.c:393 __fput+0x232/0x780 fs/file_table.c:209 IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready ____fput+0x9/0x10 fs/file_table.c:243 task_work_run+0x111/0x180 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:192 [inline] exit_to_usermode_loop+0x180/0x1e0 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_32_irqs_on arch/x86/entry/common.c:341 [inline] do_fast_syscall_32+0x8cb/0xad4 arch/x86/entry/common.c:397 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 The buggy address belongs to the object at ffff8800a482f600 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 4 bytes inside of 96-byte region [ffff8800a482f600, ffff8800a482f660) The buggy address belongs to the page: IPv6: ADDRCONF(NETDEV_UP): wlan1: link is not ready page:ffffea0002920bc0 count:1 mapcount:0 mapping:ffff8800b6003400 index:0x0 wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 flags: 0xfff00000000100(slab) wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 raw: 00fff00000000100 ffffea0002915340 0000000800000008 ffff8800b6003400 raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page allocated via order 0, migratetype Unmovable, gfp_mask 0x6012c0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY) set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook mm/page_alloc.c:1906 [inline] prep_new_page mm/page_alloc.c:1914 [inline] get_page_from_freelist+0x2f35/0x46b0 mm/page_alloc.c:3345 __alloc_pages_nodemask+0x39e/0x2780 mm/page_alloc.c:4369 alloc_pages_current+0xd6/0x1b0 mm/mempolicy.c:2093 alloc_pages include/linux/gfp.h:492 [inline] alloc_slab_page mm/slub.c:1440 [inline] allocate_slab mm/slub.c:1585 [inline] new_slab+0x4a9/0x850 mm/slub.c:1656 new_slab_objects mm/slub.c:2419 [inline] ___slab_alloc+0x609/0x940 mm/slub.c:2571 __slab_alloc.isra.22+0x78/0xe0 mm/slub.c:2611 slab_alloc_node mm/slub.c:2674 [inline] slab_alloc mm/slub.c:2716 [inline] kmem_cache_alloc_trace+0x295/0x350 mm/slub.c:2733 kmalloc include/linux/slab.h:513 [inline] kzalloc include/linux/slab.h:707 [inline] aa_alloc_file_ctx security/apparmor/include/file.h:60 [inline] apparmor_file_alloc_security+0x394/0x900 security/apparmor/lsm.c:438 security_file_alloc+0x3a/0x70 security/security.c:879 get_empty_filp+0x127/0x390 fs/file_table.c:128 path_openat+0xb5/0x2290 fs/namei.c:3516 IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready do_filp_open+0x177/0x250 fs/namei.c:3574 do_sys_open+0x1dc/0x360 fs/open.c:1101 __do_sys_open fs/open.c:1119 [inline] __se_sys_open fs/open.c:1114 [inline] __x64_sys_open+0x79/0xb0 fs/open.c:1114 do_syscall_64+0xda/0x540 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Memory state around the buggy address: ffff8800a482f500: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc ffff8800a482f580: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff8800a482f600: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff8800a482f680: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff8800a482f700: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ==================================================================