================================================================== BUG: KASAN: slab-use-after-free in find_endpoint+0x2a3/0x2c0 drivers/usb/gadget/udc/dummy_hcd.c:1618 Read of size 1 at addr ffff88802cab7ce8 by task dhcpcd/5443 CPU: 2 UID: 101 PID: 5443 Comm: dhcpcd Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595 find_endpoint+0x2a3/0x2c0 drivers/usb/gadget/udc/dummy_hcd.c:1618 handle_control_request drivers/usb/gadget/udc/dummy_hcd.c:1761 [inline] dummy_timer+0x259e/0x3700 drivers/usb/gadget/udc/dummy_hcd.c:1942 __run_hrtimer kernel/time/hrtimer.c:2067 [inline] __hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2124 hrtimer_run_softirq+0x1ca/0x360 kernel/time/hrtimer.c:2141 handle_softirqs+0x1e6/0x9d0 kernel/softirq.c:645 __do_softirq kernel/softirq.c:679 [inline] invoke_softirq kernel/softirq.c:519 [inline] __irq_exit_rcu+0x194/0x210 kernel/softirq.c:767 irq_exit_rcu+0x9/0x30 kernel/softirq.c:784 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:sk_filter include/linux/filter.h:1180 [inline] RIP: 0010:unix_dgram_sendmsg+0x5bf/0x1810 net/unix/af_unix.c:2179 Code: e8 f6 2d ff ff 49 89 c7 48 85 c0 0f 84 9e 07 00 00 e8 35 31 99 f7 48 8b 74 24 08 ba 01 00 00 00 4c 89 ff e8 63 fd 38 ff 31 ff <89> c6 89 44 24 18 e8 86 2b 99 f7 8b 44 24 18 85 c0 0f 85 83 0b 00 RSP: 0018:ffffc900031afa90 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffc900031afc40 RCX: 0000000000000000 RDX: ffff88802ee12580 RSI: ffffffff89aba924 RDI: 0000000000000000 RBP: ffffc900031afb40 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 1ffff92000635f60 R13: 0000000000000040 R14: ffff888031bdbb80 R15: ffff888036917700 unix_seqpacket_sendmsg+0x12a/0x1d0 net/unix/af_unix.c:2545 sock_sendmsg_nosec net/socket.c:800 [inline] __sock_sendmsg net/socket.c:815 [inline] sock_write_iter+0x53a/0x5b0 net/socket.c:1266 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6af/0x1050 fs/read_write.c:687 ksys_write+0x1f8/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6c717d5407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007ffe8ac7cc90 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f6c7174b780 RCX: 00007f6c717d5407 RDX: 0000000000000040 RSI: 00007ffe8ac7ccf0 RDI: 0000000000000005 RBP: 0000563921945168 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffe8ac7d120 R13: 00005639500a6480 R14: 00005639508f6640 R15: 00005639508f68b0 Allocated by task 5739: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x2f8/0x6d0 mm/slub.c:5563 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] kernfs_fop_open+0x23d/0xd50 fs/kernfs/file.c:634 do_dentry_open+0x6ab/0x14d0 fs/open.c:996 vfs_open+0x82/0x3f0 fs/open.c:1101 do_open fs/namei.c:4837 [inline] path_openat+0x19fa/0x2440 fs/namei.c:5000 do_file_open+0x20e/0x430 fs/namei.c:5029 do_sys_openat2+0x10f/0x1e0 fs/open.c:1417 do_sys_open fs/open.c:1423 [inline] __do_sys_openat fs/open.c:1439 [inline] __se_sys_openat fs/open.c:1434 [inline] __x64_sys_openat+0x12d/0x210 fs/open.c:1434 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5739: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2748 [inline] slab_free mm/slub.c:6499 [inline] kfree+0x22b/0x6d0 mm/slub.c:6792 kernfs_fop_release+0x12c/0x1f0 fs/kernfs/file.c:779 __fput+0x3ff/0xb50 fs/file_table.c:512 fput_close_sync+0x118/0x250 fs/file_table.c:617 __do_sys_close fs/open.c:1560 [inline] __se_sys_close fs/open.c:1545 [inline] __x64_sys_close+0x8b/0x120 fs/open.c:1545 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88802cab7c00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 232 bytes inside of freed 512-byte region [ffff88802cab7c00, ffff88802cab7e00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802cab6400 pfn:0x2cab4 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000240 ffff88801c042c80 ffffea0000b91510 ffffea0000a16c10 raw: ffff88802cab6400 0000000000100005 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88801c042c80 ffffea0000b91510 ffffea0000a16c10 head: ffff88802cab6400 0000000000100005 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffffffffffff01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 7086, tgid 7084 (syz.3.389), ts 80272507489 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871 prep_new_page mm/page_alloc.c:1879 [inline] get_page_from_freelist+0x110d/0x35b0 mm/page_alloc.c:3943 __alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436 alloc_slab_page mm/slub.c:3347 [inline] allocate_slab mm/slub.c:3462 [inline] new_slab+0xa9/0x6e0 mm/slub.c:3513 refill_objects+0xe3/0x410 mm/slub.c:7410 refill_sheaf mm/slub.c:2885 [inline] __pcs_replace_empty_main+0x35e/0x650 mm/slub.c:4774 alloc_from_pcs mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:4984 [inline] __kmalloc_cache_noprof+0x4f4/0x6d0 mm/slub.c:5559 _kmalloc_noprof include/linux/slab.h:991 [inline] snd_mixer_oss_build_test+0x7a/0x380 sound/core/oss/mixer_oss.c:893 snd_mixer_oss_build_test_all+0x444/0x6e0 sound/core/oss/mixer_oss.c:973 snd_mixer_oss_build_input+0x139/0xd50 sound/core/oss/mixer_oss.c:1017 snd_mixer_oss_build sound/core/oss/mixer_oss.c:1276 [inline] snd_mixer_oss_notify_handler+0x48d/0x990 sound/core/oss/mixer_oss.c:1344 snd_card_register+0x2af/0x760 sound/core/init.c:935 f_midi2_create_card drivers/usb/gadget/function/f_midi2.c:1616 [inline] f_midi2_bind+0x1198/0x2770 drivers/usb/gadget/function/f_midi2.c:1948 usb_add_function+0x219/0x890 drivers/usb/gadget/composite.c:333 configfs_composite_bind+0xd83/0x1960 drivers/usb/gadget/configfs.c:1802 gadget_bind_driver+0x28c/0xbf0 drivers/usb/gadget/udc/core.c:1662 page last free pid 6251 tgid 6251 ts 77025280344 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1418 [inline] __free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4683 [inline] slab_alloc_node mm/slub.c:4996 [inline] kmem_cache_alloc_noprof+0x269/0x6a0 mm/slub.c:5010 alloc_filename fs/namei.c:147 [inline] do_getname+0x35/0x390 fs/namei.c:187 getname_flags fs/namei.c:230 [inline] getname include/linux/fs.h:2557 [inline] class_filename_constructor include/linux/fs.h:2584 [inline] __do_sys_unlink fs/namei.c:5753 [inline] __se_sys_unlink fs/namei.c:5751 [inline] __x64_sys_unlink+0x36/0x70 fs/namei.c:5751 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88802cab7b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802cab7c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802cab7c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802cab7d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802cab7d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: e8 f6 2d ff ff call 0xffff2dfb 5: 49 89 c7 mov %rax,%r15 8: 48 85 c0 test %rax,%rax b: 0f 84 9e 07 00 00 je 0x7af 11: e8 35 31 99 f7 call 0xf799314b 16: 48 8b 74 24 08 mov 0x8(%rsp),%rsi 1b: ba 01 00 00 00 mov $0x1,%edx 20: 4c 89 ff mov %r15,%rdi 23: e8 63 fd 38 ff call 0xff38fd8b 28: 31 ff xor %edi,%edi * 2a: 89 c6 mov %eax,%esi <-- trapping instruction 2c: 89 44 24 18 mov %eax,0x18(%rsp) 30: e8 86 2b 99 f7 call 0xf7992bbb 35: 8b 44 24 18 mov 0x18(%rsp),%eax 39: 85 c0 test %eax,%eax 3b: 0f .byte 0xf 3c: 85 .byte 0x85 3d: 83 0b 00 orl $0x0,(%rbx)