================================================================== BUG: KASAN: slab-use-after-free in __list_del_entry_valid_or_report+0x198/0x1b0 lib/list_debug.c:62 Read of size 8 at addr ffff888050299048 by task syz-executor.4/18095 CPU: 1 PID: 18095 Comm: syz-executor.4 Not tainted 6.6.0-syzkaller-14614-g77fa2fbe87fc #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xc4/0x620 mm/kasan/report.c:475 kasan_report+0xda/0x110 mm/kasan/report.c:588 __list_del_entry_valid_or_report+0x198/0x1b0 lib/list_debug.c:62 __list_del_entry_valid include/linux/list.h:124 [inline] __list_del_entry include/linux/list.h:215 [inline] list_del include/linux/list.h:229 [inline] ptp_release+0xc4/0x2b0 drivers/ptp/ptp_chardev.c:147 posix_clock_release+0xa4/0x160 kernel/time/posix-clock.c:157 __fput+0x270/0xbb0 fs/file_table.c:394 __fput_sync+0x47/0x50 fs/file_table.c:475 __do_sys_close fs/open.c:1590 [inline] __se_sys_close fs/open.c:1575 [inline] __x64_sys_close+0x87/0xf0 fs/open.c:1575 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7fcb5607b9da Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 03 7f 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 63 7f 02 00 8b 44 24 RSP: 002b:00007ffdf7ee0d20 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fcb5607b9da RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000032 R08: 0000001b31520000 R09: 000000000000000c R10: 000000008172f89b R11: 0000000000000293 R12: 00007fcb55c01000 R13: ffffffffffffffff R14: 00007fcb55c00000 R15: 00000000000705e1 Allocated by task 18100: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0xa3/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] ptp_open+0xe3/0x4f0 drivers/ptp/ptp_chardev.c:112 posix_clock_open+0x17e/0x240 kernel/time/posix-clock.c:134 chrdev_open+0x26d/0x6e0 fs/char_dev.c:414 do_dentry_open+0x8d4/0x18d0 fs/open.c:948 do_open fs/namei.c:3622 [inline] path_openat+0x1d4e/0x2c40 fs/namei.c:3779 do_filp_open+0x1de/0x430 fs/namei.c:3809 do_sys_openat2+0x176/0x1e0 fs/open.c:1440 do_sys_open fs/open.c:1455 [inline] __do_sys_openat fs/open.c:1471 [inline] __se_sys_openat fs/open.c:1466 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1466 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b Freed by task 18098: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x138/0x190 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:164 [inline] __cache_free mm/slab.c:3370 [inline] __do_kmem_cache_free mm/slab.c:3557 [inline] __kmem_cache_free+0xcc/0x3d0 mm/slab.c:3564 ptp_release+0x204/0x2b0 drivers/ptp/ptp_chardev.c:150 posix_clock_release+0xa4/0x160 kernel/time/posix-clock.c:157 __fput+0x270/0xbb0 fs/file_table.c:394 __fput_sync+0x47/0x50 fs/file_table.c:475 __do_sys_close fs/open.c:1590 [inline] __se_sys_close fs/open.c:1575 [inline] __x64_sys_close+0x87/0xf0 fs/open.c:1575 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b The buggy address belongs to the object at ffff888050298000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 4168 bytes inside of freed 8192-byte region [ffff888050298000, ffff88805029a000) The buggy address belongs to the physical page: page:ffffea000140a600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x50298 head:ffffea000140a600 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0x1() raw: 00fff00000000840 ffff888013040a00 ffffea0001f6bf10 ffffea0001462610 raw: 0000000000000000 ffff888050298000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0x3420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_HARDWALL|__GFP_THISNODE), pid 18100, tgid 18098 (syz-executor.0), ts 460348439015, free_ts 458178143027 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1544 [inline] get_page_from_freelist+0xa25/0x36c0 mm/page_alloc.c:3312 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4568 __alloc_pages_node include/linux/gfp.h:238 [inline] kmem_getpages mm/slab.c:1356 [inline] cache_grow_begin+0x99/0x3a0 mm/slab.c:2550 cache_alloc_refill+0x294/0x3a0 mm/slab.c:2923 ____cache_alloc mm/slab.c:2999 [inline] ____cache_alloc mm/slab.c:2982 [inline] __do_cache_alloc mm/slab.c:3182 [inline] slab_alloc_node mm/slab.c:3230 [inline] __kmem_cache_alloc_node+0x3ba/0x460 mm/slab.c:3521 kmalloc_trace+0x25/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] ptp_open+0xe3/0x4f0 drivers/ptp/ptp_chardev.c:112 posix_clock_open+0x17e/0x240 kernel/time/posix-clock.c:134 chrdev_open+0x26d/0x6e0 fs/char_dev.c:414 do_dentry_open+0x8d4/0x18d0 fs/open.c:948 do_open fs/namei.c:3622 [inline] path_openat+0x1d4e/0x2c40 fs/namei.c:3779 do_filp_open+0x1de/0x430 fs/namei.c:3809 do_sys_openat2+0x176/0x1e0 fs/open.c:1440 do_sys_open fs/open.c:1455 [inline] __do_sys_openat fs/open.c:1471 [inline] __se_sys_openat fs/open.c:1466 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1466 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1137 [inline] free_unref_page_prepare+0x4f8/0xa90 mm/page_alloc.c:2347 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2487 slab_destroy mm/slab.c:1608 [inline] slabs_destroy+0x85/0xc0 mm/slab.c:1628 cache_flusharray mm/slab.c:3341 [inline] ___cache_free+0x2b7/0x420 mm/slab.c:3404 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x4c/0x1b0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slab.h:763 [inline] slab_alloc_node mm/slab.c:3237 [inline] slab_alloc mm/slab.c:3246 [inline] __kmem_cache_alloc_lru mm/slab.c:3423 [inline] kmem_cache_alloc+0x159/0x3f0 mm/slab.c:3432 getname_flags.part.0+0x50/0x4e0 fs/namei.c:140 getname_flags+0x9c/0xf0 include/linux/audit.h:321 user_path_at_empty+0x2c/0x60 fs/namei.c:2910 do_readlinkat+0xdd/0x310 fs/stat.c:490 __do_sys_readlink fs/stat.c:523 [inline] __se_sys_readlink fs/stat.c:520 [inline] __x64_sys_readlink+0x78/0xb0 fs/stat.c:520 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b Memory state around the buggy address: ffff888050298f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888050298f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888050299000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888050299080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888050299100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb 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