audit: type=1400 audit(1515568140.445:31): avc: denied { write } for pid=6794 comm="syz-executor1" name="net" dev="proc" ino=13170 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=dir permissive=1 ================================================================== BUG: KASAN: slab-out-of-bounds in __lock_acquire+0x2eff/0x3640 kernel/locking/lockdep.c:3224 Read of size 8 at addr ffff8801d6bac5f8 by task syz-executor5/6816 CPU: 1 PID: 6816 Comm: syz-executor5 Not tainted 4.9.75-g8910fa5 #19 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801c3def7e0 ffffffff81d93049 ffffea00075aeb00 ffff8801d6bac5f8 0000000000000000 ffff8801d6bac5f8 ffff8801d6bac5f8 ffff8801c3def818 ffffffff8153ca53 ffff8801d6bac5f8 0000000000000008 0000000000000000 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] print_address_description+0x73/0x280 mm/kasan/report.c:252 [] kasan_report_error mm/kasan/report.c:351 [inline] [] kasan_report+0x275/0x360 mm/kasan/report.c:408 [] __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:429 [] __lock_acquire+0x2eff/0x3640 kernel/locking/lockdep.c:3224 [] lock_acquire+0x12e/0x410 kernel/locking/lockdep.c:3756 [] __raw_write_lock_irqsave include/linux/rwlock_api_smp.h:186 [inline] [] _raw_write_lock_irqsave+0x4e/0x62 kernel/locking/spinlock.c:303 [] sg_remove_request+0x70/0x120 drivers/scsi/sg.c:2122 [] sg_finish_rem_req+0x295/0x340 drivers/scsi/sg.c:1838 [] sg_read+0xa1c/0x1440 drivers/scsi/sg.c:527 [] __vfs_read+0x103/0x670 fs/read_write.c:452 [] vfs_read+0x11e/0x380 fs/read_write.c:475 [] SYSC_read fs/read_write.c:591 [inline] [] SyS_read+0xd9/0x1b0 fs/read_write.c:584 [] do_syscall_32_irqs_on arch/x86/entry/common.c:322 [inline] [] do_fast_syscall_32+0x2f7/0x890 arch/x86/entry/common.c:384 [] entry_SYSENTER_compat+0x74/0x83 arch/x86/entry/entry_64_compat.S:127 Allocated by task 6803: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57 save_stack+0x43/0xd0 mm/kasan/kasan.c:505 set_track mm/kasan/kasan.c:517 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:609 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:547 slab_post_alloc_hook mm/slab.h:417 [inline] slab_alloc_node mm/slub.c:2715 [inline] slab_alloc mm/slub.c:2723 [inline] kmem_cache_alloc+0xba/0x290 mm/slub.c:2728 fasync_alloc fs/fcntl.c:604 [inline] fasync_add_entry fs/fcntl.c:662 [inline] fasync_helper+0x37/0xb0 fs/fcntl.c:691 sg_fasync+0x86/0xb0 drivers/scsi/sg.c:1203 ioctl_fioasync fs/ioctl.c:534 [inline] do_vfs_ioctl+0x2d8/0x1140 fs/ioctl.c:639 C_SYSC_ioctl fs/compat_ioctl.c:1624 [inline] compat_SyS_ioctl+0x4da/0x2050 fs/compat_ioctl.c:1549 do_syscall_32_irqs_on arch/x86/entry/common.c:322 [inline] do_fast_syscall_32+0x2f7/0x890 arch/x86/entry/common.c:384 entry_SYSENTER_compat+0x74/0x83 arch/x86/entry/entry_64_compat.S:127 Freed by task 0: (stack is not available) The buggy address belongs to the object at ffff8801d6bac580 which belongs to the cache fasync_cache of size 96 The buggy address is located 24 bytes to the right of 96-byte region [ffff8801d6bac580, ffff8801d6bac5e0) The buggy address belongs to the page: page:ffffea00075aeb00 count:1 mapcount:0 mapping: (null) index:0x0 flags: 0x8000000000000080(slab) page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d6bac480: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc ffff8801d6bac500: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff8801d6bac580: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc ^ ffff8801d6bac600: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff8801d6bac680: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc ==================================================================