syzbot

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BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x471/0x4b0 net/rose/rose_timer.c:183
Read of size 2 at addr ffff8880565e782a by task syz.3.1440/11088

CPU: 1 UID: 0 PID: 11088 Comm: syz.3.1440 Not tainted 6.16.0-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 rose_timer_expiry+0x471/0x4b0 net/rose/rose_timer.c:183
 call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1747
 expire_timers kernel/time/timer.c:1798 [inline]
 __run_timers kernel/time/timer.c:2372 [inline]
 __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384
 run_timer_base kernel/time/timer.c:2393 [inline]
 run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403
 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:1050 [inline]
 sysvec_apic_timer_interrupt+0x57/0xc0 arch/x86/kernel/apic/apic.c:1050
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0033:0x7f6ec6fb6999
Code: 1d 13 00 00 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 83 e7 02 74 0b c3 66 2e 0f 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 <8b> 90 08 03 00 00 48 8d b8 08 03 00 00 89 d1 89 d0 83 e1 fd f0 0f
RSP: 002b:00007ffe243be418 EFLAGS: 00000246
RAX: 0000555556d24500 RBX: 00007f6ec71b5fa0 RCX: 00007f6ec6fc1425
RDX: 00007ffe243be460 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f6ec71b7ba0 R08: 0000000000000000 R09: 7fffffffffffffff
R10: 0000000000000000 R11: 0000000000000293 R12: 000000000008853c
R13: 00007f6ec71b6160 R14: ffffffffffffffff R15: 00007ffe243be5a0
 </TASK>

Allocated by task 5857:
 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:4359
 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:964
 vfs_open+0x3b/0x340 fs/open.c:1094
 do_open fs/namei.c:3896 [inline]
 path_openat+0x2ee5/0x3830 fs/namei.c:4055
 do_filp_open+0x1fa/0x410 fs/namei.c:4082
 do_sys_openat2+0x121/0x1c0 fs/open.c:1437
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_openat fs/open.c:1468 [inline]
 __se_sys_openat fs/open.c:1463 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1463
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5857:
 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:2381 [inline]
 slab_free mm/slub.c:4643 [inline]
 kfree+0x18e/0x440 mm/slub.c:4842
 kernfs_fop_release+0x160/0x190 fs/kernfs/file.c:768
 __fput+0x449/0xa70 fs/file_table.c:465
 fput_close_sync+0x119/0x200 fs/file_table.c:570
 __do_sys_close fs/open.c:1589 [inline]
 __se_sys_close fs/open.c:1574 [inline]
 __x64_sys_close+0x7f/0x110 fs/open.c:1574
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8880565e7800
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 42 bytes inside of
 freed 512-byte region [ffff8880565e7800, ffff8880565e7a00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x565e4
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801a441c80 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801a441c80 dead000000000100 dead000000000122
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0001597901 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 5848, tgid 5848 (syz-executor), ts 100502138867, free_ts 31340268051
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x21d5/0x22b0 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab+0x8a/0x3b0 mm/slub.c:2619
 new_slab mm/slub.c:2673 [inline]
 ___slab_alloc+0xbfc/0x1480 mm/slub.c:3859
 __slab_alloc mm/slub.c:3949 [inline]
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 __do_kmalloc_node mm/slub.c:4327 [inline]
 __kmalloc_noprof+0x305/0x4f0 mm/slub.c:4340
 kmalloc_noprof include/linux/slab.h:909 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 fib6_info_alloc+0x30/0xf0 net/ipv6/ip6_fib.c:155
 ip6_route_info_create+0x142/0x860 net/ipv6/route.c:3811
 addrconf_f6i_alloc+0x1d2/0x450 net/ipv6/route.c:4679
 ipv6_add_addr+0x56e/0x1090 net/ipv6/addrconf.c:1121
 add_addr+0x8b/0x2d0 net/ipv6/addrconf.c:3200
 add_v4_addrs+0x70c/0xbd0 net/ipv6/addrconf.c:3262
 addrconf_gre_config net/ipv6/addrconf.c:3543 [inline]
 addrconf_init_auto_addrs+0x75f/0xab0 net/ipv6/addrconf.c:3558
 addrconf_notify+0xacc/0x1010 net/ipv6/addrconf.c:3739
 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85
page last free pid 1 tgid 1 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0xc65/0xe60 mm/page_alloc.c:2706
 __free_pages mm/page_alloc.c:5071 [inline]
 free_contig_range+0x1bd/0x4a0 mm/page_alloc.c:6927
 destroy_args+0x7e/0x5d0 mm/debug_vm_pgtable.c:1009
 debug_vm_pgtable+0x412/0x450 mm/debug_vm_pgtable.c:1389
 do_one_initcall+0x233/0x820 init/main.c:1274
 do_initcall_level+0x137/0x1f0 init/main.c:1336
 do_initcalls+0x69/0xd0 init/main.c:1352
 kernel_init_freeable+0x3d9/0x570 init/main.c:1584
 kernel_init+0x1d/0x1d0 init/main.c:1474
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff8880565e7700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880565e7780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880565e7800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff8880565e7880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880565e7900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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