loop4: detected capacity change from 0 to 8 ================================================================== BUG: KASAN: slab-use-after-free in squashfs_page_actor_free fs/squashfs/page_actor.h:41 [inline] BUG: KASAN: slab-use-after-free in squashfs_readahead+0x210c/0x2680 fs/squashfs/file.c:626 Read of size 4 at addr ffff888023788bc0 by task syz.4.1052/9541 CPU: 0 UID: 0 PID: 9541 Comm: syz.4.1052 Not tainted 6.11.0-rc4-next-20240822-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 squashfs_page_actor_free fs/squashfs/page_actor.h:41 [inline] squashfs_readahead+0x210c/0x2680 fs/squashfs/file.c:626 read_pages+0x17e/0x840 mm/readahead.c:160 page_cache_ra_unbounded+0x6ce/0x7f0 mm/readahead.c:273 page_cache_sync_readahead include/linux/pagemap.h:1296 [inline] filemap_get_pages+0x543/0x2330 mm/filemap.c:2529 filemap_splice_read+0x654/0xeb0 mm/filemap.c:2897 do_splice_read fs/splice.c:985 [inline] splice_direct_to_actor+0x4b7/0xc90 fs/splice.c:1089 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0x28c/0x3e0 fs/splice.c:1233 ovl_copy_up_file+0x5d2/0x810 fs/overlayfs/copy_up.c:334 ovl_copy_up_tmpfile fs/overlayfs/copy_up.c:863 [inline] ovl_do_copy_up fs/overlayfs/copy_up.c:976 [inline] ovl_copy_up_one fs/overlayfs/copy_up.c:1168 [inline] ovl_copy_up_flags+0x1f4e/0x4470 fs/overlayfs/copy_up.c:1223 ovl_link+0x85/0x320 fs/overlayfs/dir.c:716 vfs_link+0x4f5/0x690 fs/namei.c:4739 do_linkat+0x555/0x6f0 fs/namei.c:4809 __do_sys_link fs/namei.c:4843 [inline] __se_sys_link fs/namei.c:4841 [inline] __x64_sys_link+0x82/0x90 fs/namei.c:4841 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7febb2379e79 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007febb30b2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000056 RAX: ffffffffffffffda RBX: 00007febb2515f80 RCX: 00007febb2379e79 RDX: 0000000000000000 RSI: 0000000020000300 RDI: 0000000020000200 RBP: 00007febb23e793e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007febb2515f80 R15: 00007ffdaca7f898 Allocated by task 9541: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x19c/0x2c0 mm/slub.c:4237 kmalloc_noprof include/linux/slab.h:681 [inline] squashfs_page_actor_init_special+0x64/0x440 fs/squashfs/page_actor.c:113 squashfs_readahead+0x188f/0x2680 fs/squashfs/file.c:619 read_pages+0x17e/0x840 mm/readahead.c:160 page_cache_ra_unbounded+0x6ce/0x7f0 mm/readahead.c:273 page_cache_sync_readahead include/linux/pagemap.h:1296 [inline] filemap_get_pages+0x543/0x2330 mm/filemap.c:2529 filemap_splice_read+0x654/0xeb0 mm/filemap.c:2897 do_splice_read fs/splice.c:985 [inline] splice_direct_to_actor+0x4b7/0xc90 fs/splice.c:1089 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0x28c/0x3e0 fs/splice.c:1233 ovl_copy_up_file+0x5d2/0x810 fs/overlayfs/copy_up.c:334 ovl_copy_up_tmpfile fs/overlayfs/copy_up.c:863 [inline] ovl_do_copy_up fs/overlayfs/copy_up.c:976 [inline] ovl_copy_up_one fs/overlayfs/copy_up.c:1168 [inline] ovl_copy_up_flags+0x1f4e/0x4470 fs/overlayfs/copy_up.c:1223 ovl_link+0x85/0x320 fs/overlayfs/dir.c:716 vfs_link+0x4f5/0x690 fs/namei.c:4739 do_linkat+0x555/0x6f0 fs/namei.c:4809 __do_sys_link fs/namei.c:4843 [inline] __se_sys_link fs/namei.c:4841 [inline] __x64_sys_link+0x82/0x90 fs/namei.c:4841 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 9541: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2299 [inline] slab_free mm/slub.c:4521 [inline] kfree+0x196/0x3e0 mm/slub.c:4669 squashfs_page_actor_free fs/squashfs/page_actor.h:39 [inline] squashfs_readahead+0x195b/0x2680 fs/squashfs/file.c:626 read_pages+0x17e/0x840 mm/readahead.c:160 page_cache_ra_unbounded+0x6ce/0x7f0 mm/readahead.c:273 page_cache_sync_readahead include/linux/pagemap.h:1296 [inline] filemap_get_pages+0x543/0x2330 mm/filemap.c:2529 filemap_splice_read+0x654/0xeb0 mm/filemap.c:2897 do_splice_read fs/splice.c:985 [inline] splice_direct_to_actor+0x4b7/0xc90 fs/splice.c:1089 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0x28c/0x3e0 fs/splice.c:1233 ovl_copy_up_file+0x5d2/0x810 fs/overlayfs/copy_up.c:334 ovl_copy_up_tmpfile fs/overlayfs/copy_up.c:863 [inline] ovl_do_copy_up fs/overlayfs/copy_up.c:976 [inline] ovl_copy_up_one fs/overlayfs/copy_up.c:1168 [inline] ovl_copy_up_flags+0x1f4e/0x4470 fs/overlayfs/copy_up.c:1223 ovl_link+0x85/0x320 fs/overlayfs/dir.c:716 vfs_link+0x4f5/0x690 fs/namei.c:4739 do_linkat+0x555/0x6f0 fs/namei.c:4809 __do_sys_link fs/namei.c:4843 [inline] __se_sys_link fs/namei.c:4841 [inline] __x64_sys_link+0x82/0x90 fs/namei.c:4841 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888023788b80 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 64 bytes inside of freed 96-byte region [ffff888023788b80, ffff888023788be0) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x23788 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xfdffffff(slab) raw: 00fff00000000000 ffff888015841280 ffffea000075f640 dead000000000004 raw: 0000000000000000 0000000080200020 00000001fdffffff 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 0x152820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 62, tgid 62 (kworker/u8:4), ts 60626322003, free_ts 60318686970 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1517 prep_new_page mm/page_alloc.c:1525 [inline] get_page_from_freelist+0x3131/0x3280 mm/page_alloc.c:3476 __alloc_pages_noprof+0x29e/0x780 mm/page_alloc.c:4743 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] alloc_pages_node_noprof include/linux/gfp.h:296 [inline] alloc_slab_page+0x5f/0x120 mm/slub.c:2368 allocate_slab+0x5a/0x2f0 mm/slub.c:2531 new_slab mm/slub.c:2584 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3771 __slab_alloc+0x58/0xa0 mm/slub.c:3861 __slab_alloc_node mm/slub.c:3914 [inline] slab_alloc_node mm/slub.c:4073 [inline] __kmalloc_cache_noprof+0x1d5/0x2c0 mm/slub.c:4232 kmalloc_noprof include/linux/slab.h:681 [inline] dst_cow_metrics_generic+0x56/0x1c0 net/core/dst.c:178 dst_metrics_write_ptr include/net/dst.h:133 [inline] dst_metric_set include/net/dst.h:194 [inline] icmp6_dst_alloc+0x270/0x420 net/ipv6/route.c:3288 ndisc_send_skb+0x32a/0x1380 net/ipv6/ndisc.c:491 ndisc_send_ns+0xcc/0x160 net/ipv6/ndisc.c:669 addrconf_dad_work+0xb45/0x16f0 net/ipv6/addrconf.c:4284 process_one_work kernel/workqueue.c:3232 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3313 worker_thread+0x86d/0xd10 kernel/workqueue.c:3390 kthread+0x2f0/0x390 kernel/kthread.c:389 page last free pid 62 tgid 62 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1098 [inline] free_unref_page+0xc07/0xd90 mm/page_alloc.c:2651 __slab_free+0x31b/0x3d0 mm/slub.c:4432 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9e/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4036 [inline] slab_alloc_node mm/slub.c:4085 [inline] kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4128 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:667 alloc_skb include/linux/skbuff.h:1320 [inline] alloc_skb_with_frags+0xc3/0x770 net/core/skbuff.c:6563 sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2815 sock_alloc_send_skb include/net/sock.h:1778 [inline] mld_newpack+0x1c3/0xa90 net/ipv6/mcast.c:1746 add_grhead net/ipv6/mcast.c:1849 [inline] add_grec+0x1492/0x19a0 net/ipv6/mcast.c:1987 mld_send_initial_cr+0x228/0x4b0 net/ipv6/mcast.c:2233 ipv6_mc_dad_complete+0x88/0x490 net/ipv6/mcast.c:2244 addrconf_dad_completed+0x712/0xcd0 net/ipv6/addrconf.c:4342 addrconf_dad_work+0xdc2/0x16f0 process_one_work kernel/workqueue.c:3232 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3313 Memory state around the buggy address: ffff888023788a80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff888023788b00: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc >ffff888023788b80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff888023788c00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff888023788c80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ==================================================================