================================================================== BUG: KASAN: slab-out-of-bounds in memcmp lib/string.c:757 [inline] BUG: KASAN: slab-out-of-bounds in bcmp+0xbe/0x1e0 lib/string.c:789 Read of size 8 at addr ffff888147d65d88 by task syz-executor.0/32621 CPU: 1 PID: 32621 Comm: syz-executor.0 Not tainted 6.0.0-rc4-syzkaller-00302-gb96fbd602d35 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 print_address_description+0x65/0x4b0 mm/kasan/report.c:317 print_report+0x108/0x220 mm/kasan/report.c:433 kasan_report+0xfb/0x130 mm/kasan/report.c:495 memcmp lib/string.c:757 [inline] bcmp+0xbe/0x1e0 lib/string.c:789 fscache_volume_same fs/fscache/volume.c:133 [inline] fscache_hash_volume fs/fscache/volume.c:171 [inline] __fscache_acquire_volume+0x751/0x10c0 fs/fscache/volume.c:328 fscache_acquire_volume include/linux/fscache.h:204 [inline] v9fs_cache_session_get_cookie+0x12e/0x1c0 fs/9p/cache.c:34 v9fs_session_init+0x159e/0x1990 fs/9p/v9fs.c:473 v9fs_mount+0xd2/0xcb0 fs/9p/vfs_super.c:126 legacy_get_tree+0xea/0x180 fs/fs_context.c:610 vfs_get_tree+0x88/0x270 fs/super.c:1530 do_new_mount+0x289/0xad0 fs/namespace.c:3040 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3568 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f1139e893c9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f113b08f168 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f1139f9bf80 RCX: 00007f1139e893c9 RDX: 0000000020000240 RSI: 00000000200000c0 RDI: 0000000020000000 RBP: 00007f1139ee433f R08: 00000000200004c0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffcaf5096bf R14: 00007f113b08f300 R15: 0000000000022000 Allocated by task 32621: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:437 [inline] ____kasan_kmalloc+0xdc/0x110 mm/kasan/common.c:516 kasan_kmalloc include/linux/kasan.h:234 [inline] __kmalloc+0x226/0x370 mm/slub.c:4424 kmalloc include/linux/slab.h:605 [inline] kzalloc include/linux/slab.h:733 [inline] fscache_alloc_volume fs/fscache/volume.c:234 [inline] __fscache_acquire_volume+0x335/0x10c0 fs/fscache/volume.c:323 fscache_acquire_volume include/linux/fscache.h:204 [inline] v9fs_cache_session_get_cookie+0x12e/0x1c0 fs/9p/cache.c:34 v9fs_session_init+0x159e/0x1990 fs/9p/v9fs.c:473 v9fs_mount+0xd2/0xcb0 fs/9p/vfs_super.c:126 legacy_get_tree+0xea/0x180 fs/fs_context.c:610 vfs_get_tree+0x88/0x270 fs/super.c:1530 do_new_mount+0x289/0xad0 fs/namespace.c:3040 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3568 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:348 insert_work+0x54/0x3e0 kernel/workqueue.c:1358 __queue_work+0xa31/0xce0 kernel/workqueue.c:1517 queue_work_on+0x137/0x240 kernel/workqueue.c:1545 queue_work include/linux/workqueue.h:503 [inline] call_usermodehelper_exec+0x26d/0x430 kernel/umh.c:435 call_modprobe kernel/kmod.c:98 [inline] __request_module+0x395/0x790 kernel/kmod.c:170 dev_load+0x130/0x190 net/core/dev_ioctl.c:449 dev_ioctl+0x3b2/0xf30 net/core/dev_ioctl.c:514 sock_do_ioctl+0x26a/0x450 net/socket.c:1183 sock_ioctl+0x481/0x770 net/socket.c:1286 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff888147d65d00 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 136 bytes inside of 192-byte region [ffff888147d65d00, ffff888147d65dc0) The buggy address belongs to the physical page: page:ffffea00051f5940 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x147d65 flags: 0x57ff00000000200(slab|node=1|zone=2|lastcpupid=0x7ff) raw: 057ff00000000200 ffffea0005145240 dead000000000004 ffff888012041a00 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 1, tgid 1 (swapper/0), ts 7719468234, free_ts 0 prep_new_page mm/page_alloc.c:2532 [inline] get_page_from_freelist+0x72b/0x7a0 mm/page_alloc.c:4283 __alloc_pages+0x259/0x560 mm/page_alloc.c:5515 alloc_page_interleave+0x22/0x1c0 mm/mempolicy.c:2103 alloc_slab_page+0x70/0xf0 mm/slub.c:1824 allocate_slab+0x5e/0x520 mm/slub.c:1969 new_slab mm/slub.c:2029 [inline] ___slab_alloc+0x42e/0xce0 mm/slub.c:3031 __slab_alloc mm/slub.c:3118 [inline] slab_alloc_node mm/slub.c:3209 [inline] slab_alloc mm/slub.c:3251 [inline] kmem_cache_alloc_trace+0x25f/0x310 mm/slub.c:3282 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:733 [inline] call_usermodehelper_setup+0x8a/0x260 kernel/umh.c:365 kobject_uevent_env+0x7c1/0x8e0 lib/kobject_uevent.c:614 really_probe+0x794/0x9f0 drivers/base/dd.c:687 __driver_probe_device+0x1f4/0x3f0 drivers/base/dd.c:778 driver_probe_device+0x50/0x240 drivers/base/dd.c:808 __device_attach_driver+0x272/0x3c0 drivers/base/dd.c:936 bus_for_each_drv+0x18a/0x210 drivers/base/bus.c:427 __device_attach+0x372/0x5a0 drivers/base/dd.c:1008 bus_probe_device+0xb8/0x1f0 drivers/base/bus.c:487 page_owner free stack trace missing Memory state around the buggy address: ffff888147d65c80: 04 fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888147d65d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888147d65d80: 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888147d65e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888147d65e80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================