random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) random: cc1: uninitialized urandom read (8 bytes read) ================================================================== BUG: KASAN: use-after-free in mqueue_get_tree+0x2ac/0x2e0 ipc/mqueue.c:362 Read of size 8 at addr ffff8801d7cc0688 by task syz-executor4/5584 CPU: 0 PID: 5584 Comm: syz-executor4 Not tainted 4.19.0-rc3-next-20180912+ #72 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+0x1d3/0x2c4 lib/dump_stack.c:113 print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 mqueue_get_tree+0x2ac/0x2e0 ipc/mqueue.c:362 vfs_get_tree+0x1cb/0x5c0 fs/super.c:1787 mq_create_mount+0xe3/0x190 ipc/mqueue.c:415 mq_init_ns+0x15a/0x210 ipc/mqueue.c:1621 create_ipc_ns ipc/namespace.c:58 [inline] copy_ipcs+0x3d2/0x580 ipc/namespace.c:84 create_new_namespaces+0x376/0x900 kernel/nsproxy.c:87 unshare_nsproxy_namespaces+0xc3/0x1f0 kernel/nsproxy.c:206 ksys_unshare+0x79c/0x10b0 kernel/fork.c:2535 __do_sys_unshare kernel/fork.c:2603 [inline] __se_sys_unshare kernel/fork.c:2601 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:2601 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459d87 Code: 00 00 00 b8 63 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 3d 8a fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 10 01 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 1d 8a fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffddc9e7fb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459d87 RDX: 0000000000000000 RSI: 00007ffddc9e7fc0 RDI: 0000000008000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000018 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000412c30 R13: 0000000000412cc0 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 3455: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490 kmem_cache_alloc+0x12e/0x730 mm/slab.c:3554 getname_flags+0xd0/0x5a0 fs/namei.c:140 getname fs/namei.c:211 [inline] do_symlinkat+0x8b/0x2d0 fs/namei.c:4143 __do_sys_symlink fs/namei.c:4173 [inline] __se_sys_symlink fs/namei.c:4171 [inline] __x64_sys_symlink+0x59/0x80 fs/namei.c:4171 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 3455: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kmem_cache_free+0x83/0x290 mm/slab.c:3756 putname+0xf2/0x130 fs/namei.c:261 do_symlinkat+0x18c/0x2d0 fs/namei.c:4161 __do_sys_symlink fs/namei.c:4173 [inline] __se_sys_symlink fs/namei.c:4171 [inline] __x64_sys_symlink+0x59/0x80 fs/namei.c:4171 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8801d7cc0540 which belongs to the cache names_cache of size 4096 The buggy address is located 328 bytes inside of 4096-byte region [ffff8801d7cc0540, ffff8801d7cc1540) The buggy address belongs to the page: page:ffffea00075f3000 count:1 mapcount:0 mapping:ffff8801da972d80 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000008100(slab|head) raw: 02fffc0000008100 ffffea00075fa788 ffffea00075f0b08 ffff8801da972d80 raw: 0000000000000000 ffff8801d7cc0540 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d7cc0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801d7cc0600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801d7cc0680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801d7cc0700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801d7cc0780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================