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BUG: KASAN: use-after-free in snd_mask_test include/sound/pcm_params.h:141 [inline]
BUG: KASAN: use-after-free in snd_pcm_oss_get_formats+0x320/0x380 sound/core/oss/pcm_oss.c:1770
Read of size 4 at addr ffff8801b57144a4 by task syz-executor1/16829

CPU: 0 PID: 16829 Comm: syz-executor1 Not tainted 4.16.0-rc4+ #346
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x24d lib/dump_stack.c:53
 print_address_description+0x73/0x250 mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report+0x23c/0x360 mm/kasan/report.c:412
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432
 snd_mask_test include/sound/pcm_params.h:141 [inline]
 snd_pcm_oss_get_formats+0x320/0x380 sound/core/oss/pcm_oss.c:1770
 snd_pcm_oss_set_format sound/core/oss/pcm_oss.c:1784 [inline]
 snd_pcm_oss_ioctl+0x1e2f/0x39f0 sound/core/oss/pcm_oss.c:2515
 vfs_ioctl fs/ioctl.c:46 [inline]
 do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x453e69
RSP: 002b:00007f0be8b37c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f0be8b386d4 RCX: 0000000000453e69
RDX: 0000000020000080 RSI: 00800000c0045005 RDI: 0000000000000014
RBP: 000000000072bf58 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000357 R14: 00000000006f50c8 R15: 0000000000000001

Allocated by task 16829:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:552
 kmem_cache_alloc_trace+0x136/0x740 mm/slab.c:3607
 kmalloc include/linux/slab.h:512 [inline]
 snd_pcm_oss_get_formats+0x1c7/0x380 sound/core/oss/pcm_oss.c:1760
 snd_pcm_oss_set_format sound/core/oss/pcm_oss.c:1784 [inline]
 snd_pcm_oss_ioctl+0x1e2f/0x39f0 sound/core/oss/pcm_oss.c:2515
 vfs_ioctl fs/ioctl.c:46 [inline]
 do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Freed by task 16829:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:520
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:527
 __cache_free mm/slab.c:3485 [inline]
 kfree+0xd9/0x260 mm/slab.c:3800
 snd_pcm_oss_get_formats+0x216/0x380 sound/core/oss/pcm_oss.c:1766
 snd_pcm_oss_set_format sound/core/oss/pcm_oss.c:1784 [inline]
 snd_pcm_oss_ioctl+0x1e2f/0x39f0 sound/core/oss/pcm_oss.c:2515
 vfs_ioctl fs/ioctl.c:46 [inline]
 do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

The buggy address belongs to the object at ffff8801b5714480
 which belongs to the cache kmalloc-1024 of size 1024
The buggy address is located 36 bytes inside of
 1024-byte region [ffff8801b5714480, ffff8801b5714880)
The buggy address belongs to the page:
page:ffffea0006d5c500 count:1 mapcount:0 mapping:ffff8801b5714000 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffff8801b5714000 0000000000000000 0000000100000007
raw: ffffea0006d4dd20 ffffea0006bea4a0 ffff8801dac00ac0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801b5714380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801b5714400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8801b5714480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff8801b5714500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801b5714580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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