================================================================== BUG: KASAN: use-after-free in sixpack_close+0x180/0x1f0 drivers/net/hamradio/6pack.c:678 Read of size 8 at addr ffff88809004ec90 by task syz-executor.0/5752 CPU: 0 PID: 5752 Comm: syz-executor.0 Not tainted 5.16.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106 print_address_description+0x65/0x380 mm/kasan/report.c:247 __kasan_report mm/kasan/report.c:433 [inline] kasan_report+0x19a/0x1f0 mm/kasan/report.c:450 sixpack_close+0x180/0x1f0 drivers/net/hamradio/6pack.c:678 tty_ldisc_close drivers/tty/tty_ldisc.c:474 [inline] tty_ldisc_kill drivers/tty/tty_ldisc.c:629 [inline] tty_ldisc_hangup+0x5bc/0x7e0 drivers/tty/tty_ldisc.c:749 __tty_hangup+0x4e5/0x730 drivers/tty/tty_io.c:639 tty_vhangup drivers/tty/tty_io.c:711 [inline] tty_ioctl+0x8ae/0x17d0 drivers/tty/tty_io.c:2745 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fe315d86ae9 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe3132fc188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fe315e99f60 RCX: 00007fe315d86ae9 RDX: 0000000020000100 RSI: 0000000000005437 RDI: 0000000000000004 RBP: 00007fe315de0f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffef3bc02cf R14: 00007fe3132fc300 R15: 0000000000022000 Allocated by task 25158: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc+0xdc/0x110 mm/kasan/common.c:513 kasan_kmalloc include/linux/kasan.h:269 [inline] __kmalloc_node+0x28e/0x420 mm/slub.c:4471 kmalloc_node include/linux/slab.h:613 [inline] kvmalloc_node+0x81/0x110 mm/util.c:587 kvmalloc include/linux/slab.h:741 [inline] kvzalloc include/linux/slab.h:749 [inline] alloc_netdev_mqs+0x85/0xc40 net/core/dev.c:10828 sixpack_open+0xe6/0x9e0 drivers/net/hamradio/6pack.c:558 tty_ldisc_open drivers/tty/tty_ldisc.c:449 [inline] tty_set_ldisc+0x530/0x950 drivers/tty/tty_ldisc.c:579 tiocsetd drivers/tty/tty_io.c:2455 [inline] tty_ioctl+0x1477/0x17d0 drivers/tty/tty_io.c:2741 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 5752: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0x10d/0x150 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:1723 [inline] slab_free_freelist_hook+0x12e/0x1a0 mm/slub.c:1749 slab_free mm/slub.c:3513 [inline] kfree+0xe1/0x330 mm/slub.c:4561 device_release+0x98/0x1c0 kobject_cleanup+0x1c0/0x280 lib/kobject.c:705 netdev_run_todo+0xb59/0xcf0 net/core/dev.c:10638 unregister_netdev+0x1a0/0x210 net/core/dev.c:11137 sixpack_close+0x169/0x1f0 drivers/net/hamradio/6pack.c:675 tty_ldisc_close drivers/tty/tty_ldisc.c:474 [inline] tty_ldisc_kill drivers/tty/tty_ldisc.c:629 [inline] tty_ldisc_hangup+0x5bc/0x7e0 drivers/tty/tty_ldisc.c:749 __tty_hangup+0x4e5/0x730 drivers/tty/tty_io.c:639 tty_vhangup drivers/tty/tty_io.c:711 [inline] tty_ioctl+0x8ae/0x17d0 drivers/tty/tty_io.c:2745 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff88809004e000 which belongs to the cache kmalloc-cg-4k of size 4096 The buggy address is located 3216 bytes inside of 4096-byte region [ffff88809004e000, ffff88809004f000) The buggy address belongs to the page: page:ffffea0002401200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x90048 head:ffffea0002401200 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff88801184c280 raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 25124, ts 563228099648, free_ts 562834505713 prep_new_page mm/page_alloc.c:2418 [inline] get_page_from_freelist+0x729/0x9e0 mm/page_alloc.c:4149 __alloc_pages+0x255/0x580 mm/page_alloc.c:5369 alloc_slab_page mm/slub.c:1793 [inline] allocate_slab+0xcc/0x4d0 mm/slub.c:1930 new_slab mm/slub.c:1993 [inline] ___slab_alloc+0x41e/0xc40 mm/slub.c:3022 __slab_alloc mm/slub.c:3109 [inline] slab_alloc_node mm/slub.c:3200 [inline] __kmalloc_node+0x2ec/0x420 mm/slub.c:4467 kmalloc_node include/linux/slab.h:613 [inline] kvmalloc_node+0x81/0x110 mm/util.c:587 kvmalloc include/linux/slab.h:741 [inline] kvzalloc include/linux/slab.h:749 [inline] kvm_recalculate_apic_map+0x469/0x1050 arch/x86/kvm/lapic.c:214 kvm_apic_set_state+0x4e9/0x21c0 arch/x86/kvm/lapic.c:2628 kvm_vcpu_ioctl_set_lapic arch/x86/kvm/x86.c:4462 [inline] kvm_arch_vcpu_ioctl+0x122d/0x4e60 arch/x86/kvm/x86.c:5103 kvm_vcpu_ioctl+0x77a/0xe20 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3865 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1338 [inline] free_pcp_prepare+0xd1c/0xe00 mm/page_alloc.c:1389 free_unref_page_prepare mm/page_alloc.c:3309 [inline] free_unref_page+0x7d/0x580 mm/page_alloc.c:3388 free_slab mm/slub.c:2033 [inline] discard_slab mm/slub.c:2039 [inline] __unfreeze_partials+0x1ab/0x200 mm/slub.c:2527 put_cpu_partial+0x116/0x180 mm/slub.c:2603 do_slab_free mm/slub.c:3501 [inline] ___cache_free+0xe6/0x120 mm/slub.c:3520 qlist_free_all mm/kasan/quarantine.c:165 [inline] kasan_quarantine_reduce+0x151/0x1c0 mm/kasan/quarantine.c:272 __kasan_slab_alloc+0x2f/0xf0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:259 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc_node mm/slub.c:3234 [inline] slab_alloc mm/slub.c:3242 [inline] __kmalloc+0x1ed/0x380 mm/slub.c:4419 kmalloc include/linux/slab.h:595 [inline] kzalloc include/linux/slab.h:724 [inline] tomoyo_encode2+0x25a/0x560 security/tomoyo/realpath.c:45 tomoyo_encode security/tomoyo/realpath.c:80 [inline] tomoyo_realpath_from_path+0x5c3/0x610 security/tomoyo/realpath.c:288 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x238/0x660 security/tomoyo/file.c:822 security_inode_getattr+0xc0/0x140 security/security.c:1334 vfs_getattr fs/stat.c:157 [inline] vfs_statx+0x168/0x3f0 fs/stat.c:225 vfs_fstatat fs/stat.c:243 [inline] vfs_lstat include/linux/fs.h:3358 [inline] __do_sys_newlstat fs/stat.c:398 [inline] __se_sys_newlstat+0xba/0x750 fs/stat.c:392 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Memory state around the buggy address: ffff88809004eb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88809004ec00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88809004ec80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88809004ed00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88809004ed80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================