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KASAN: slab-use-after-free Read in rose_transmit_link

Status: upstream: reported on 2025/07/04 12:14
Reported-by: syzbot+02f1358d2e1fa9bc544e@syzkaller.appspotmail.com
First crash: 17d, last: 11d
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in rose_transmit_link (3) hams 10 27 490d 1117d 0/29 auto-obsoleted due to no activity on 2024/06/26 03:46
upstream general protection fault in rose_transmit_link (2) hams 2 3 1247d 1264d 0/29 auto-closed as invalid on 2022/05/21 05:59
linux-6.1 KASAN: use-after-free Read in rose_transmit_link 19 16 1d19h 74d 0/3 upstream: reported on 2025/05/08 04:31
linux-4.19 general protection fault in rose_transmit_link 2 1 1269d 1269d 0/1 auto-closed as invalid on 2022/05/29 13:41
linux-5.15 KASAN: use-after-free Read in rose_transmit_link 19 C 44 1d03h 79d 0/3 upstream: reported C repro on 2025/05/03 13:00

Sample crash report:
==================================================================
BUG: KASAN: slab-use-after-free in rose_transmit_link+0x5ba/0x740 net/rose/rose_link.c:266
Read of size 1 at addr ffff88805c477832 by task syz.3.588/8059

CPU: 0 PID: 8059 Comm: syz.3.588 Not tainted 6.6.95-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0xac/0x230 mm/kasan/report.c:475
 kasan_report+0x117/0x150 mm/kasan/report.c:588
 rose_transmit_link+0x5ba/0x740 net/rose/rose_link.c:266
 rose_write_internal+0x11d1/0x1ab0 net/rose/rose_subr.c:198
 rose_release+0x24e/0x510 net/rose/af_rose.c:671
 __sock_release net/socket.c:659 [inline]
 sock_close+0xbd/0x230 net/socket.c:1421
 __fput+0x234/0x970 fs/file_table.c:384
 task_work_run+0x1ce/0x250 kernel/task_work.c:239
 get_signal+0x1235/0x1400 kernel/signal.c:2678
 arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f55da18e929
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:00007f55daf55038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: fffffffffffffe00 RBX: 00007f55da3b6080 RCX: 00007f55da18e929
RDX: 0000000000000040 RSI: 0000200000000100 RDI: 0000000000000007
RBP: 00007f55da210b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f55da3b6080 R15: 00007fff0fb55a88
 </TASK>

Allocated by task 7399:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4e/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:383
 kmalloc include/linux/slab.h:600 [inline]
 rose_add_node+0x23a/0xdd0 net/rose/rose_route.c:85
 rose_rt_ioctl+0xa42/0xfb0 net/rose/rose_route.c:747
 rose_ioctl+0x3cf/0x8b0 net/rose/af_rose.c:1380
 sock_do_ioctl+0xd7/0x2f0 net/socket.c:1222
 sock_ioctl+0x623/0x7a0 net/socket.c:1341
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Freed by task 8053:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4e/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522
 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:164 [inline]
 slab_free_hook mm/slub.c:1806 [inline]
 slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1832
 slab_free mm/slub.c:3816 [inline]
 __kmem_cache_free+0xba/0x1f0 mm/slub.c:3829
 rose_rt_device_down+0x66d/0x6c0 net/rose/rose_route.c:522
 rose_device_event+0x604/0x690 net/rose/af_rose.c:248
 notifier_call_chain+0x197/0x390 kernel/notifier.c:93
 call_netdevice_notifiers_extack net/core/dev.c:2064 [inline]
 call_netdevice_notifiers net/core/dev.c:2078 [inline]
 __dev_notify_flags+0x18e/0x2e0 net/core/dev.c:-1
 dev_change_flags+0xe8/0x1a0 net/core/dev.c:8750
 dev_ifsioc+0x6a7/0xe20 net/core/dev_ioctl.c:529
 dev_ioctl+0x7e2/0x1170 net/core/dev_ioctl.c:786
 sock_do_ioctl+0x226/0x2f0 net/socket.c:1236
 sock_ioctl+0x623/0x7a0 net/socket.c:1341
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Last potentially related work creation:
 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492
 insert_work+0x3d/0x310 kernel/workqueue.c:1651
 __queue_work+0xd2c/0x1020 kernel/workqueue.c:1804
 call_timer_fn+0x16e/0x530 kernel/time/timer.c:1700
 expire_timers kernel/time/timer.c:1746 [inline]
 __run_timers+0x558/0x7d0 kernel/time/timer.c:2022
 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2035
 handle_softirqs+0x280/0x820 kernel/softirq.c:578
 __do_softirq kernel/softirq.c:612 [inline]
 invoke_softirq kernel/softirq.c:452 [inline]
 __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687

Second to last potentially related work creation:
 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492
 __call_rcu_common kernel/rcu/tree.c:2717 [inline]
 call_rcu+0x14f/0x920 kernel/rcu/tree.c:2833
 fib6_info_release include/net/ip6_fib.h:339 [inline]
 ip6_route_info_create+0x9c0/0x1200 net/ipv6/route.c:3875
 ip6_route_add+0x28/0x130 net/ipv6/route.c:3889
 addrconf_prefix_route+0x211/0x2b0 net/ipv6/addrconf.c:2451
 inet6_addr_add+0x64a/0xb60 net/ipv6/addrconf.c:3035
 inet6_rtm_newaddr+0x68d/0x940 net/ipv6/addrconf.c:5009
 rtnetlink_rcv_msg+0x7c7/0xf10 net/core/rtnetlink.c:6475
 netlink_rcv_skb+0x216/0x480 net/netlink/af_netlink.c:2537
 netlink_unicast_kernel net/netlink/af_netlink.c:1323 [inline]
 netlink_unicast+0x750/0x8c0 net/netlink/af_netlink.c:1349
 netlink_sendmsg+0x8c1/0xbe0 net/netlink/af_netlink.c:1891
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 __sys_sendto+0x46a/0x620 net/socket.c:2201
 __do_sys_sendto net/socket.c:2213 [inline]
 __se_sys_sendto net/socket.c:2209 [inline]
 __x64_sys_sendto+0xde/0xf0 net/socket.c:2209
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff88805c477800
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 50 bytes inside of
 freed 512-byte region [ffff88805c477800, ffff88805c477a00)

The buggy address belongs to the physical page:
page:ffffea0001711d00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5c474
head:ffffea0001711d00 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000840 ffff888017841c80 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000100010 00000001ffffffff 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5784, tgid 5784 (syz-executor), ts 63687684212, free_ts 15673237501
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554
 prep_new_page mm/page_alloc.c:1561 [inline]
 get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191
 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457
 alloc_slab_page+0x5d/0x170 mm/slub.c:1876
 allocate_slab mm/slub.c:2023 [inline]
 new_slab+0x87/0x2e0 mm/slub.c:2076
 ___slab_alloc+0xc6d/0x12f0 mm/slub.c:3230
 __slab_alloc mm/slub.c:3329 [inline]
 __slab_alloc_node mm/slub.c:3382 [inline]
 slab_alloc_node mm/slub.c:3475 [inline]
 __kmem_cache_alloc_node+0x1a2/0x260 mm/slub.c:3524
 __do_kmalloc_node mm/slab_common.c:1006 [inline]
 __kmalloc+0xa4/0x240 mm/slab_common.c:1020
 kmalloc include/linux/slab.h:604 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 fib6_info_alloc+0x32/0xe0 net/ipv6/ip6_fib.c:155
 ip6_route_info_create+0x44f/0x1200 net/ipv6/route.c:3793
 ip6_route_add+0x28/0x130 net/ipv6/route.c:3889
 addrconf_add_mroute net/ipv6/addrconf.c:2515 [inline]
 addrconf_add_dev+0x257/0x340 net/ipv6/addrconf.c:2533
 inet6_addr_add+0x215/0xb60 net/ipv6/addrconf.c:2996
 inet6_rtm_newaddr+0x68d/0x940 net/ipv6/addrconf.c:5009
 rtnetlink_rcv_msg+0x7c7/0xf10 net/core/rtnetlink.c:6475
 netlink_rcv_skb+0x216/0x480 net/netlink/af_netlink.c:2537
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1154 [inline]
 free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336
 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429
 free_contig_range+0xa1/0x160 mm/page_alloc.c:6369
 destroy_args+0x87/0x770 mm/debug_vm_pgtable.c:1015
 debug_vm_pgtable+0x3cc/0x410 mm/debug_vm_pgtable.c:1395
 do_one_initcall+0x1fd/0x750 init/main.c:1238
 do_initcall_level+0x137/0x1f0 init/main.c:1300
 do_initcalls+0x69/0xd0 init/main.c:1316
 kernel_init_freeable+0x3d2/0x570 init/main.c:1553
 kernel_init+0x1d/0x1c0 init/main.c:1443
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293

Memory state around the buggy address:
 ffff88805c477700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88805c477780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88805c477800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff88805c477880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805c477900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/04 12:14 linux-6.6.y 3f5b4c104b7d 76ad128c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in rose_transmit_link
2025/07/09 17:54 linux-6.6.y a5df3a702b2c f4e5e155 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-out-of-bounds Read in rose_transmit_link
* Struck through repros no longer work on HEAD.