================================================================== BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x471/0x4b0 net/rose/rose_timer.c:183 Read of size 2 at addr ffff8880311cf82a by task syz-executor/11733 CPU: 0 UID: 0 PID: 11733 Comm: syz-executor Not tainted 6.15.0-rc4-syzkaller-00152-g4397684a292a #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xb4/0x290 mm/kasan/report.c:521 kasan_report+0x118/0x150 mm/kasan/report.c:634 rose_timer_expiry+0x471/0x4b0 net/rose/rose_timer.c:183 call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1789 expire_timers kernel/time/timer.c:1840 [inline] __run_timers kernel/time/timer.c:2414 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2426 run_timer_base kernel/time/timer.c:2435 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2445 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:seqcount_lockdep_reader_access+0x129/0x180 include/linux/seqlock.h:75 Code: a3 b1 ff 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b 41 f7 c5 00 02 00 00 74 01 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 27 00 00 00 00 66 43 c7 44 27 09 00 00 43 c6 44 27 0b 00 RSP: 0018:ffffc90004eff780 EFLAGS: 00000206 RAX: 30384cec03961e00 RBX: ffff88813fffbc58 RCX: 30384cec03961e00 RDX: 0000000000000000 RSI: ffffffff8d749ecb RDI: ffffffff8bc1cde0 RBP: ffffc90004eff830 R08: ffffffff8f7ed377 R09: 1ffffffff1efda6e R10: dffffc0000000000 R11: fffffbfff1efda6f R12: dffffc0000000000 R13: 0000000000000a06 R14: ffffffff821592a5 R15: 1ffff920009dfef0 read_seqbegin include/linux/seqlock.h:836 [inline] zone_span_seqbegin include/linux/memory_hotplug.h:103 [inline] page_outside_zone_boundaries mm/page_alloc.c:441 [inline] bad_range+0x55/0x290 mm/page_alloc.c:460 rmqueue mm/page_alloc.c:3176 [inline] get_page_from_freelist+0x21ac/0x22b0 mm/page_alloc.c:3685 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4970 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301 alloc_frozen_pages_noprof mm/mempolicy.c:2372 [inline] alloc_pages_noprof+0xa9/0x190 mm/mempolicy.c:2392 vm_area_alloc_pages mm/vmalloc.c:3591 [inline] __vmalloc_area_node mm/vmalloc.c:3669 [inline] __vmalloc_node_range_noprof+0x8fe/0x12c0 mm/vmalloc.c:3844 vmalloc_user_noprof+0x74/0x80 mm/vmalloc.c:3996 kcov_ioctl+0x55/0x640 kernel/kcov.c:716 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9e7b18e56b Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007ffee72e2800 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000080000 RCX: 00007f9e7b18e56b RDX: 0000000000080000 RSI: ffffffff80086301 RDI: 00000000000000d9 RBP: 00007f9e7b3b6118 R08: 00000000000000d8 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000 Allocated by task 11056: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4372 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] rpc_mkpipe_data+0x59/0x390 net/sunrpc/rpc_pipe.c:567 nfs4blocklayout_net_init+0x85/0x1e0 fs/nfs/blocklayout/rpc_pipefs.c:239 ops_init+0x359/0x5c0 net/core/net_namespace.c:138 setup_net+0x238/0x830 net/core/net_namespace.c:364 copy_net_ns+0x32e/0x590 net/core/net_namespace.c:518 create_new_namespaces+0x3d3/0x700 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:228 ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3375 __do_sys_unshare kernel/fork.c:3446 [inline] __se_sys_unshare kernel/fork.c:3444 [inline] __x64_sys_unshare+0x38/0x50 kernel/fork.c:3444 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 66: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2398 [inline] slab_free mm/slub.c:4656 [inline] kfree+0x193/0x440 mm/slub.c:4855 nfs4blocklayout_net_exit+0xdb/0x130 fs/nfs/blocklayout/rpc_pipefs.c:256 ops_exit_list net/core/net_namespace.c:172 [inline] cleanup_net+0x717/0xbd0 net/core/net_namespace.c:654 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff8880311cf800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 42 bytes inside of freed 512-byte region [ffff8880311cf800, ffff8880311cfa00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8880311cf800 pfn:0x311cc head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000240 ffff88801a041c80 ffffea00008f5610 ffffea0000c7d710 raw: ffff8880311cf800 000000000010000a 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88801a041c80 ffffea00008f5610 ffffea0000c7d710 head: ffff8880311cf800 000000000010000a 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea0000c47301 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5201, tgid 5201 (udevd), ts 92118869918, free_ts 91531454193 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1d8/0x230 mm/page_alloc.c:1718 prep_new_page mm/page_alloc.c:1726 [inline] get_page_from_freelist+0x21ce/0x22b0 mm/page_alloc.c:3688 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4970 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301 alloc_slab_page mm/slub.c:2468 [inline] allocate_slab+0x8a/0x3b0 mm/slub.c:2632 new_slab mm/slub.c:2686 [inline] ___slab_alloc+0xbfc/0x1480 mm/slub.c:3872 __slab_alloc mm/slub.c:3962 [inline] __slab_alloc_node mm/slub.c:4037 [inline] slab_alloc_node mm/slub.c:4198 [inline] __kmalloc_cache_noprof+0x296/0x3d0 mm/slub.c:4367 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] kernfs_fop_open+0x397/0xca0 fs/kernfs/file.c:623 do_dentry_open+0xdf0/0x1970 fs/open.c:956 vfs_open+0x3b/0x340 fs/open.c:1086 do_open fs/namei.c:3880 [inline] path_openat+0x2ee5/0x3830 fs/namei.c:4039 do_filp_open+0x1fa/0x410 fs/namei.c:4066 do_sys_openat2+0x121/0x1c0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_openat fs/open.c:1460 [inline] __se_sys_openat fs/open.c:1455 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1455 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 52 tgid 52 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1262 [inline] __free_frozen_pages+0xb0e/0xcd0 mm/page_alloc.c:2725 vfree+0x1a6/0x330 mm/vmalloc.c:3383 pcpu_mem_free mm/percpu.c:523 [inline] pcpu_free_chunk mm/percpu.c:1489 [inline] pcpu_destroy_chunk mm/percpu-vm.c:368 [inline] pcpu_balance_free+0x6ae/0x940 mm/percpu.c:1977 pcpu_balance_workfn+0xd01/0xe00 mm/percpu.c:2206 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff8880311cf700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880311cf780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880311cf800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880311cf880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880311cf900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: a3 b1 ff 48 c7 44 24 movabs %eax,0x202444c748ffb1 7: 20 00 9: 00 00 add %al,(%rax) b: 00 9c 8f 44 24 20 f6 add %bl,-0x9dfdbbc(%rdi,%rcx,4) 12: 44 24 21 rex.R and $0x21,%al 15: 02 75 4b add 0x4b(%rbp),%dh 18: 41 f7 c5 00 02 00 00 test $0x200,%r13d 1f: 74 01 je 0x22 21: fb sti 22: 48 c7 04 24 0e 36 e0 movq $0x45e0360e,(%rsp) 29: 45 * 2a: 4b c7 04 27 00 00 00 movq $0x0,(%r15,%r12,1) <-- trapping instruction 31: 00 32: 66 43 c7 44 27 09 00 movw $0x0,0x9(%r15,%r12,1) 39: 00 3a: 43 c6 44 27 0b 00 movb $0x0,0xb(%r15,%r12,1)