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KASAN: use-after-free Read in macsec_get_iflink (2)

Status: upstream: reported C repro on 2024/11/02 16:17
Reported-by: syzbot+2de3ad92b239326eb338@syzkaller.appspotmail.com
First crash: 247d, last: 8d01h
▶ ▼ Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-15 KASAN: use-after-free Read in macsec_get_iflink (2) 1 79d 79d 0/2 premoderation: reported on 2025/04/20 01:08
android-5-10 KASAN: use-after-free Read in macsec_get_iflink syz error 2 401d 528d 0/2 auto-obsoleted due to no activity on 2024/08/30 07:40
android-5-15 KASAN: use-after-free Read in macsec_get_iflink 1 804d 804d 0/2 auto-obsoleted due to no activity on 2023/07/24 21:03
upstream KASAN: use-after-free Read in macsec_get_iflink net 1 1141d 1137d 22/29 fixed on 2023/02/24 13:50
▶ ▼ Last patch testing requests (7)
Created Duration User Patch Repo Result
2025/04/26 23:28 14m retest repro android13-5.10-lts report log
2025/04/26 23:28 6m retest repro android13-5.10-lts report log
2025/02/05 11:14 11m retest repro android13-5.10-lts report log
2025/02/05 11:14 5m retest repro android13-5.10-lts report log
2024/11/27 10:23 19m retest repro android13-5.10-lts report log
2024/11/27 10:23 15m retest repro android13-5.10-lts report log
2024/11/27 10:23 8m retest repro android13-5.10-lts report log
▶ ▼ Fix bisection attempts (5)
Created Duration User Patch Repo Result
2025/06/29 23:28 1h57m bisect fix android13-5.10-lts OK (0) job log log
2025/05/30 18:32 2h50m bisect fix android13-5.10-lts OK (0) job log log
2025/04/12 03:55 2h54m bisect fix android13-5.10-lts OK (0) job log log
2025/03/07 13:50 3h33m bisect fix android13-5.10-lts OK (0) job log log
2025/01/11 15:59 2h28m bisect fix android13-5.10-lts OK (0) job log log

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in macsec_get_iflink+0x70/0x80 drivers/net/macsec.c:3654
Read of size 4 at addr ffff88810fb68100 by task kworker/u4:1/9

CPU: 0 PID: 9 Comm: kworker/u4:1 Not tainted 5.10.226-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events_unbound linkwatch_event
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack_lvl+0x1e2/0x24b lib/dump_stack.c:118
 print_address_description+0x81/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:435 [inline]
 kasan_report+0x179/0x1c0 mm/kasan/report.c:452
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308
 macsec_get_iflink+0x70/0x80 drivers/net/macsec.c:3654
 dev_get_iflink+0x6f/0xc0 net/core/dev.c:824
 default_operstate net/core/link_watch.c:41 [inline]
 rfc2863_policy+0x127/0x2b0 net/core/link_watch.c:53
 linkwatch_do_dev+0x3c/0x140 net/core/link_watch.c:160
 __linkwatch_run_queue+0x4ca/0x7f0 net/core/link_watch.c:213
 linkwatch_event+0x4c/0x60 net/core/link_watch.c:252
 process_one_work+0x6dc/0xbd0 kernel/workqueue.c:2301
 worker_thread+0xaea/0x1510 kernel/workqueue.c:2447
 kthread+0x34b/0x3d0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

Allocated by task 298:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:430 [inline]
 ____kasan_kmalloc+0xdb/0x110 mm/kasan/common.c:509
 __kasan_kmalloc+0x9/0x10 mm/kasan/common.c:518
 kasan_kmalloc include/linux/kasan.h:254 [inline]
 __kmalloc+0x1aa/0x330 mm/slub.c:4033
 __kmalloc_node include/linux/slab.h:418 [inline]
 kmalloc_node include/linux/slab.h:575 [inline]
 kvmalloc_node+0x82/0x130 mm/util.c:612
 kvmalloc include/linux/mm.h:822 [inline]
 kvzalloc include/linux/mm.h:830 [inline]
 alloc_netdev_mqs+0x8e/0xcd0 net/core/dev.c:10507
 rtnl_create_link+0x240/0x950 net/core/rtnetlink.c:3192
 veth_newlink+0x287/0xb50 drivers/net/veth.c:1344
 __rtnl_newlink net/core/rtnetlink.c:3479 [inline]
 rtnl_newlink+0x1516/0x2000 net/core/rtnetlink.c:3527
 rtnetlink_rcv_msg+0x955/0xc50 net/core/rtnetlink.c:5607
 netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2499
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5625
 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline]
 netlink_unicast+0x8df/0xac0 net/netlink/af_netlink.c:1348
 netlink_sendmsg+0xa46/0xd00 net/netlink/af_netlink.c:1916
 sock_sendmsg_nosec net/socket.c:652 [inline]
 __sock_sendmsg net/socket.c:664 [inline]
 __sys_sendto+0x545/0x700 net/socket.c:2006
 __do_sys_sendto net/socket.c:2018 [inline]
 __se_sys_sendto net/socket.c:2014 [inline]
 __x64_sys_sendto+0xe5/0x100 net/socket.c:2014
 do_syscall_64+0x34/0x70
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Freed by task 7:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:45
 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370
 ____kasan_slab_free+0x121/0x160 mm/kasan/common.c:362
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:370
 kasan_slab_free include/linux/kasan.h:220 [inline]
 slab_free_hook mm/slub.c:1595 [inline]
 slab_free_freelist_hook+0xc0/0x190 mm/slub.c:1621
 slab_free mm/slub.c:3203 [inline]
 kfree+0xc3/0x270 mm/slub.c:4191
 kvfree+0x35/0x40 mm/util.c:647
 netdev_freemem+0x3f/0x60 net/core/dev.c:10461
 netdev_release+0x7f/0xb0 net/core/net-sysfs.c:1886
 device_release+0x95/0x1c0
 kobject_cleanup lib/kobject.c:713 [inline]
 kobject_release lib/kobject.c:744 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x178/0x260 lib/kobject.c:761
 netdev_run_todo+0xc26/0xdc0 net/core/dev.c:10332
 rtnl_unlock+0xe/0x10 net/core/rtnetlink.c:112
 default_device_exit_batch+0x38f/0x3f0 net/core/dev.c:11268
 ops_exit_list net/core/net_namespace.c:190 [inline]
 cleanup_net+0x6e9/0xcb0 net/core/net_namespace.c:609
 process_one_work+0x6dc/0xbd0 kernel/workqueue.c:2301
 worker_thread+0xaea/0x1510 kernel/workqueue.c:2447
 kthread+0x34b/0x3d0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

The buggy address belongs to the object at ffff88810fb68000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 256 bytes inside of
 4096-byte region [ffff88810fb68000, ffff88810fb69000)
The buggy address belongs to the page:
page:ffffea00043eda00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10fb68
head:ffffea00043eda00 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head)
raw: 4000000000010200 dead000000000100 dead000000000122 ffff888100042c00
raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 297, ts 24042260037, free_ts 24032658283
 set_page_owner include/linux/page_owner.h:35 [inline]
 post_alloc_hook mm/page_alloc.c:2456 [inline]
 prep_new_page+0x166/0x180 mm/page_alloc.c:2462
 get_page_from_freelist+0x2d8c/0x2f30 mm/page_alloc.c:4254
 __alloc_pages_nodemask+0x435/0xaf0 mm/page_alloc.c:5348
 allocate_slab mm/slub.c:1808 [inline]
 new_slab+0x80/0x400 mm/slub.c:1869
 new_slab_objects mm/slub.c:2627 [inline]
 ___slab_alloc+0x302/0x4b0 mm/slub.c:2791
 __slab_alloc+0x63/0xa0 mm/slub.c:2831
 slab_alloc_node mm/slub.c:2913 [inline]
 slab_alloc mm/slub.c:2955 [inline]
 __kmalloc_track_caller+0x1f8/0x320 mm/slub.c:4536
 __kmalloc_reserve net/core/skbuff.c:144 [inline]
 __alloc_skb+0xbc/0x510 net/core/skbuff.c:212
 alloc_skb include/linux/skbuff.h:1126 [inline]
 nlmsg_new include/net/netlink.h:953 [inline]
 rtmsg_ifinfo_build_skb+0x7f/0x180 net/core/rtnetlink.c:3841
 rtmsg_ifinfo_event net/core/rtnetlink.c:3877 [inline]
 rtmsg_ifinfo+0x78/0x120 net/core/rtnetlink.c:3886
 __dev_notify_flags+0xdd/0x610 net/core/dev.c:8548
 dev_change_flags+0xf0/0x1a0 net/core/dev.c:8590
 do_setlink+0xc5c/0x3c30 net/core/rtnetlink.c:2729
 __rtnl_newlink net/core/rtnetlink.c:3407 [inline]
 rtnl_newlink+0x15f0/0x2000 net/core/rtnetlink.c:3527
 rtnetlink_rcv_msg+0x955/0xc50 net/core/rtnetlink.c:5607
 netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2499
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:28 [inline]
 free_pages_prepare mm/page_alloc.c:1349 [inline]
 __free_pages_ok+0x82c/0x850 mm/page_alloc.c:1629
 free_the_page+0x76/0x370 mm/page_alloc.c:5409
 __free_pages+0x67/0xc0 mm/page_alloc.c:5418
 __free_slab+0xcf/0x190 mm/slub.c:1894
 free_slab mm/slub.c:1909 [inline]
 discard_slab mm/slub.c:1915 [inline]
 unfreeze_partials+0x15e/0x190 mm/slub.c:2410
 put_cpu_partial+0xbf/0x180 mm/slub.c:2446
 __slab_free+0x2c8/0x3a0 mm/slub.c:3095
 do_slab_free mm/slub.c:3191 [inline]
 ___cache_free+0x111/0x130 mm/slub.c:3210
 qlink_free+0x50/0x90 mm/kasan/quarantine.c:157
 qlist_free_all+0x47/0xb0 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x15a/0x170 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xe0 mm/kasan/common.c:440
 kasan_slab_alloc include/linux/kasan.h:244 [inline]
 slab_post_alloc_hook+0x61/0x2f0 mm/slab.h:583
 slab_alloc_node mm/slub.c:2947 [inline]
 slab_alloc mm/slub.c:2955 [inline]
 kmem_cache_alloc+0x168/0x2e0 mm/slub.c:2960
 sock_alloc_inode+0x1b/0xb0 net/socket.c:253
 alloc_inode fs/inode.c:233 [inline]
 new_inode_pseudo+0x64/0x220 fs/inode.c:964

Memory state around the buggy address:
 ffff88810fb68000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88810fb68080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88810fb68100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff88810fb68180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88810fb68200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/11/02 22:31 android13-5.10-lts e5e5644ea27f f00eed24 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-5-10 KASAN: use-after-free Read in macsec_get_iflink
2024/11/02 16:08 android13-5.10-lts e5e5644ea27f f00eed24 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-5-10 KASAN: use-after-free Read in macsec_get_iflink
2024/11/02 18:08 android13-5.10-lts e5e5644ea27f f00eed24 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-5-10 KASAN: use-after-free Read in macsec_get_iflink
2024/11/13 09:59 android13-5.10-lts 6a01908517df 62026c85 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in macsec_get_iflink
2024/11/02 14:33 android13-5.10-lts e5e5644ea27f f00eed24 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in macsec_get_iflink
* Struck through repros no longer work on HEAD.