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: sshd: uninitialized urandom read (32 bytes read) ================================================================== BUG: KASAN: slab-out-of-bounds in fscache_set_key fs/fscache/cookie.c:120 [inline] BUG: KASAN: slab-out-of-bounds in fscache_alloc_cookie+0x7a9/0x880 fs/fscache/cookie.c:171 Read of size 4 at addr ffff8801d2fad5a4 by task syz-executor681/4546 CPU: 0 PID: 4546 Comm: syz-executor681 Not tainted 4.18.0-rc4+ #138 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+0x1c9/0x2b4 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432 fscache_set_key fs/fscache/cookie.c:120 [inline] fscache_alloc_cookie+0x7a9/0x880 fs/fscache/cookie.c:171 __fscache_acquire_cookie+0x230/0xb00 fs/fscache/cookie.c:303 fscache_acquire_cookie include/linux/fscache.h:338 [inline] v9fs_cache_session_get_cookie+0xc4/0x270 fs/9p/cache.c:73 v9fs_session_init+0x1013/0x1a80 fs/9p/v9fs.c:464 v9fs_mount+0x7c/0x900 fs/9p/vfs_super.c:135 mount_fs+0xae/0x328 fs/super.c:1277 vfs_kern_mount.part.34+0xdc/0x4e0 fs/namespace.c:1037 vfs_kern_mount fs/namespace.c:1027 [inline] do_new_mount fs/namespace.c:2518 [inline] do_mount+0x581/0x30e0 fs/namespace.c:2848 ksys_mount+0x12d/0x140 fs/namespace.c:3064 __do_sys_mount fs/namespace.c:3078 [inline] __se_sys_mount fs/namespace.c:3075 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3075 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x440169 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffc8106fd08 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 0000000000440169 RDX: 0000000020000040 RSI: 0000000020000000 RDI: 0000000000000000 RBP: 00000000006ca018 R08: 0000000020000080 R09: 00000000004002c8 R10: 0000000000000000 R11: 0000000000000202 R12: 00000000004019f0 R13: 0000000000401a80 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 4546: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 __do_kmalloc mm/slab.c:3718 [inline] __kmalloc+0x14e/0x760 mm/slab.c:3727 kmalloc include/linux/slab.h:518 [inline] kzalloc include/linux/slab.h:707 [inline] fscache_set_key fs/fscache/cookie.c:101 [inline] fscache_alloc_cookie+0x701/0x880 fs/fscache/cookie.c:171 __fscache_acquire_cookie+0x230/0xb00 fs/fscache/cookie.c:303 fscache_acquire_cookie include/linux/fscache.h:338 [inline] v9fs_cache_session_get_cookie+0xc4/0x270 fs/9p/cache.c:73 v9fs_session_init+0x1013/0x1a80 fs/9p/v9fs.c:464 v9fs_mount+0x7c/0x900 fs/9p/vfs_super.c:135 mount_fs+0xae/0x328 fs/super.c:1277 vfs_kern_mount.part.34+0xdc/0x4e0 fs/namespace.c:1037 vfs_kern_mount fs/namespace.c:1027 [inline] do_new_mount fs/namespace.c:2518 [inline] do_mount+0x581/0x30e0 fs/namespace.c:2848 ksys_mount+0x12d/0x140 fs/namespace.c:3064 __do_sys_mount fs/namespace.c:3078 [inline] __se_sys_mount fs/namespace.c:3075 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3075 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 1: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xd9/0x260 mm/slab.c:3813 kobject_uevent_env+0x275/0x1110 lib/kobject_uevent.c:619 kobject_uevent+0x1f/0x30 lib/kobject_uevent.c:636 device_add+0x95d/0x16f0 drivers/base/core.c:1874 device_create_groups_vargs+0x1ff/0x270 drivers/base/core.c:2471 device_create_with_groups+0xe0/0x110 drivers/base/core.c:2590 misc_register+0x2e8/0x7d0 drivers/char/misc.c:206 loop_init+0x149/0x261 drivers/block/loop.c:2107 do_one_initcall+0x127/0x913 init/main.c:884 do_initcall_level init/main.c:952 [inline] do_initcalls init/main.c:960 [inline] do_basic_setup init/main.c:978 [inline] kernel_init_freeable+0x49b/0x58e init/main.c:1135 kernel_init+0x11/0x1b3 init/main.c:1061 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 The buggy address belongs to the object at ffff8801d2fad580 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 36 bytes inside of 64-byte region [ffff8801d2fad580, ffff8801d2fad5c0) The buggy address belongs to the page: page:ffffea00074beb40 count:1 mapcount:0 mapping:ffff8801da800340 index:0x0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffffea00074bcac8 ffffea00074ab808 ffff8801da800340 raw: 0000000000000000 ffff8801d2fad000 0000000100000020 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d2fad480: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ffff8801d2fad500: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc >ffff8801d2fad580: 00 00 00 00 05 fc fc fc fc fc fc fc fc fc fc fc ^ ffff8801d2fad600: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ffff8801d2fad680: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================