Extracting prog: 13m40.405648485s Minimizing prog: 30m40.911065196s Simplifying prog options: 15m13.416437536s Extracting C: 5m13.769498249s Simplifying C: 0s extracting reproducer from 1 programs testing a last program of every proc single: executing 1 programs separately with timeout 30s testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_rdma-sendmsg$RDMA_NLDEV_CMD_NEWLINK detailed listing: executing program 0: r0 = socket$nl_rdma(0x10, 0x3, 0x14) sendmsg$RDMA_NLDEV_CMD_NEWLINK(r0, &(0x7f0000000140)={0x0, 0x0, &(0x7f0000000100)={&(0x7f0000000040)={0x38, 0x1403, 0x1, 0x70bd28, 0x25dfdbfe, "", [{{0x9, 0x2, 'syz2\x00'}, {0x8, 0x41, 'rxe\x00'}, {0x14, 0x33, 'ipvlan1\x00'}}]}, 0x38}, 0x1, 0x0, 0x0, 0x4080000}, 0x10) program did not crash single: failed to extract reproducer single: executing 1 programs separately with timeout 6m0s testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_rdma-sendmsg$RDMA_NLDEV_CMD_NEWLINK detailed listing: executing program 0: r0 = socket$nl_rdma(0x10, 0x3, 0x14) sendmsg$RDMA_NLDEV_CMD_NEWLINK(r0, &(0x7f0000000140)={0x0, 0x0, &(0x7f0000000100)={&(0x7f0000000040)={0x38, 0x1403, 0x1, 0x70bd28, 0x25dfdbfe, "", [{{0x9, 0x2, 'syz2\x00'}, {0x8, 0x41, 'rxe\x00'}, {0x14, 0x33, 'ipvlan1\x00'}}]}, 0x38}, 0x1, 0x0, 0x0, 0x4080000}, 0x10) VM was preempted during syz execution: failed to run command in VM: instance is preempted, retrying program crashed: KASAN: slab-use-after-free Read in __ethtool_get_link_ksettings single: successfully extracted reproducer found reproducer with 2 syscalls minimizing guilty program testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_rdma detailed listing: executing program 0: socket$nl_rdma(0x10, 0x3, 0x14) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): sendmsg$RDMA_NLDEV_CMD_NEWLINK detailed listing: executing program 0: sendmsg$RDMA_NLDEV_CMD_NEWLINK(0xffffffffffffffff, &(0x7f0000000140)={0x0, 0x0, &(0x7f0000000100)={&(0x7f0000000040)={0x38, 0x1403, 0x1, 0x70bd28, 0x25dfdbfe, "", [{{0x9, 0x2, 'syz2\x00'}, {0x8, 0x41, 'rxe\x00'}, {0x14, 0x33, 'ipvlan1\x00'}}]}, 0x38}, 0x1, 0x0, 0x0, 0x4080000}, 0x10) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_rdma-sendmsg$RDMA_NLDEV_CMD_NEWLINK detailed listing: executing program 0: r0 = socket$nl_rdma(0x10, 0x3, 0x14) sendmsg$RDMA_NLDEV_CMD_NEWLINK(r0, 0x0, 0x10) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_rdma-sendmsg$RDMA_NLDEV_CMD_NEWLINK detailed listing: executing program 0: r0 = socket$nl_rdma(0x10, 0x3, 0x14) sendmsg$RDMA_NLDEV_CMD_NEWLINK(r0, &(0x7f0000000140)={0x0, 0x0, 0x0, 0x1, 0x0, 0x0, 0x4080000}, 0x10) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_rdma-sendmsg$RDMA_NLDEV_CMD_NEWLINK detailed listing: executing program 0: r0 = socket$nl_rdma(0x10, 0x3, 0x14) sendmsg$RDMA_NLDEV_CMD_NEWLINK(r0, &(0x7f0000000140)={0x0, 0x0, &(0x7f0000000100)={0x0}, 0x1, 0x0, 0x0, 0x4080000}, 0x10) program did not crash extracting C reproducer testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_rdma-sendmsg$RDMA_NLDEV_CMD_NEWLINK program crashed: no output from test machine a never seen crash title: no output from test machine, ignore simplifying guilty program options testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_rdma-sendmsg$RDMA_NLDEV_CMD_NEWLINK detailed listing: executing program 0: r0 = socket$nl_rdma(0x10, 0x3, 0x14) sendmsg$RDMA_NLDEV_CMD_NEWLINK(r0, &(0x7f0000000140)={0x0, 0x0, &(0x7f0000000100)={&(0x7f0000000040)={0x38, 0x1403, 0x1, 0x70bd28, 0x25dfdbfe, "", [{{0x9, 0x2, 'syz2\x00'}, {0x8, 0x41, 'rxe\x00'}, {0x14, 0x33, 'ipvlan1\x00'}}]}, 0x38}, 0x1, 0x0, 0x0, 0x4080000}, 0x10) program crashed: KASAN: slab-use-after-free Read in __ethtool_get_link_ksettings extracting C reproducer testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_rdma-sendmsg$RDMA_NLDEV_CMD_NEWLINK program crashed: no output from test machine a never seen crash title: no output from test machine, ignore testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_rdma-sendmsg$RDMA_NLDEV_CMD_NEWLINK detailed listing: executing program 0: r0 = socket$nl_rdma(0x10, 0x3, 0x14) sendmsg$RDMA_NLDEV_CMD_NEWLINK(r0, &(0x7f0000000140)={0x0, 0x0, &(0x7f0000000100)={&(0x7f0000000040)={0x38, 0x1403, 0x1, 0x70bd28, 0x25dfdbfe, "", [{{0x9, 0x2, 'syz2\x00'}, {0x8, 0x41, 'rxe\x00'}, {0x14, 0x33, 'ipvlan1\x00'}}]}, 0x38}, 0x1, 0x0, 0x0, 0x4080000}, 0x10) program did not crash testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_rdma-sendmsg$RDMA_NLDEV_CMD_NEWLINK detailed listing: executing program 0: r0 = socket$nl_rdma(0x10, 0x3, 0x14) sendmsg$RDMA_NLDEV_CMD_NEWLINK(r0, &(0x7f0000000140)={0x0, 0x0, &(0x7f0000000100)={&(0x7f0000000040)={0x38, 0x1403, 0x1, 0x70bd28, 0x25dfdbfe, "", [{{0x9, 0x2, 'syz2\x00'}, {0x8, 0x41, 'rxe\x00'}, {0x14, 0x33, 'ipvlan1\x00'}}]}, 0x38}, 0x1, 0x0, 0x0, 0x4080000}, 0x10) program crashed: KASAN: slab-use-after-free Read in __ethtool_get_link_ksettings validation run: crashed=true testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_rdma-sendmsg$RDMA_NLDEV_CMD_NEWLINK detailed listing: executing program 0: r0 = socket$nl_rdma(0x10, 0x3, 0x14) sendmsg$RDMA_NLDEV_CMD_NEWLINK(r0, &(0x7f0000000140)={0x0, 0x0, &(0x7f0000000100)={&(0x7f0000000040)={0x38, 0x1403, 0x1, 0x70bd28, 0x25dfdbfe, "", [{{0x9, 0x2, 'syz2\x00'}, {0x8, 0x41, 'rxe\x00'}, {0x14, 0x33, 'ipvlan1\x00'}}]}, 0x38}, 0x1, 0x0, 0x0, 0x4080000}, 0x10) program crashed: KASAN: slab-use-after-free Read in __ethtool_get_link_ksettings validation run: crashed=true testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_rdma-sendmsg$RDMA_NLDEV_CMD_NEWLINK detailed listing: executing program 0: r0 = socket$nl_rdma(0x10, 0x3, 0x14) sendmsg$RDMA_NLDEV_CMD_NEWLINK(r0, &(0x7f0000000140)={0x0, 0x0, &(0x7f0000000100)={&(0x7f0000000040)={0x38, 0x1403, 0x1, 0x70bd28, 0x25dfdbfe, "", [{{0x9, 0x2, 'syz2\x00'}, {0x8, 0x41, 'rxe\x00'}, {0x14, 0x33, 'ipvlan1\x00'}}]}, 0x38}, 0x1, 0x0, 0x0, 0x4080000}, 0x10) program crashed: KASAN: slab-use-after-free Read in __ethtool_get_link_ksettings validation run: crashed=true reproducing took 1h14m27.600843493s repro crashed as (corrupted=false): ================================================================== BUG: KASAN: slab-use-after-free in netdev_need_ops_lock include/net/netdev_lock.h:30 [inline] BUG: KASAN: slab-use-after-free in netdev_lock_ops include/net/netdev_lock.h:41 [inline] BUG: KASAN: slab-use-after-free in __ethtool_get_link_ksettings+0x230/0x250 net/ethtool/ioctl.c:463 Read of size 1 at addr ffff888031de2e09 by task kworker/0:0/9 CPU: 0 UID: 0 PID: 9 Comm: kworker/0:0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: events smc_ib_port_event_work Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 netdev_need_ops_lock include/net/netdev_lock.h:30 [inline] netdev_lock_ops include/net/netdev_lock.h:41 [inline] __ethtool_get_link_ksettings+0x230/0x250 net/ethtool/ioctl.c:463 __ethtool_get_link_ksettings+0x11f/0x250 net/ethtool/ioctl.c:464 ib_get_eth_speed+0x180/0x7f0 drivers/infiniband/core/verbs.c:2061 rxe_query_port+0x93/0x3d0 drivers/infiniband/sw/rxe/rxe_verbs.c:56 __ib_query_port drivers/infiniband/core/device.c:2304 [inline] ib_query_port+0x16e/0x830 drivers/infiniband/core/device.c:2336 smc_ib_remember_port_attr net/smc/smc_ib.c:364 [inline] smc_ib_port_event_work+0x147/0x920 net/smc/smc_ib.c:388 process_one_work kernel/workqueue.c:3396 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 9649: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5414 [inline] __kvmalloc_node_noprof+0x50f/0x820 mm/slub.c:7005 alloc_netdev_mqs+0xa9/0x12a0 net/core/dev.c:12117 rtnl_create_link+0x321/0xd70 net/core/rtnetlink.c:3804 rtnl_newlink_create+0x258/0x7b0 net/core/rtnetlink.c:3986 __rtnl_newlink net/core/rtnetlink.c:4125 [inline] rtnl_newlink+0x167a/0x1c30 net/core/rtnetlink.c:4242 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7159 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x7bd/0x940 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:800 __sock_sendmsg net/socket.c:815 [inline] __sys_sendto+0x408/0x5a0 net/socket.c:2281 __do_sys_sendto net/socket.c:2288 [inline] __se_sys_sendto net/socket.c:2284 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2284 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 1027: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2748 [inline] slab_free mm/slub.c:6499 [inline] kfree+0x1c5/0x650 mm/slub.c:6792 device_release+0xc4/0x1f0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x222/0x550 lib/kobject.c:737 netdev_run_todo+0xeee/0x1060 net/core/dev.c:11818 default_device_exit_batch+0x6d9/0x760 net/core/dev.c:13290 ops_exit_list net/core/net_namespace.c:206 [inline] ops_undo_list+0x4b4/0x8d0 net/core/net_namespace.c:253 cleanup_net+0x572/0x810 net/core/net_namespace.c:706 process_one_work kernel/workqueue.c:3396 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff888031de2000 which belongs to the cache kmalloc-cg-4k of size 4096 The buggy address is located 3593 bytes inside of freed 4096-byte region [ffff888031de2000, ffff888031de3000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x31de0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888031de1011 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b04b500 dead000000000100 dead000000000122 raw: 0000000000000000 0000000300040004 00000000f5000000 ffff888031de1011 head: 00fff00000000040 ffff88801b04b500 dead000000000100 dead000000000122 head: 0000000000000000 0000000300040004 00000000f5000000 ffff888031de1011 head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5768, tgid 5768 (syz-executor), ts 84976368773 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871 prep_new_page mm/page_alloc.c:1879 [inline] get_page_from_freelist+0x2209/0x2280 mm/page_alloc.c:3943 __alloc_frozen_pages_noprof+0x217/0x5a0 mm/page_alloc.c:5436 alloc_slab_page mm/slub.c:3347 [inline] allocate_slab+0x7d/0x620 mm/slub.c:3462 new_slab mm/slub.c:3513 [inline] refill_objects+0x2d5/0x350 mm/slub.c:7410 refill_sheaf mm/slub.c:2885 [inline] __pcs_replace_empty_main+0x2c8/0x6c0 mm/slub.c:4774 alloc_from_pcs mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:4984 [inline] __do_kmalloc_node mm/slub.c:5413 [inline] __kmalloc_node_track_caller_noprof+0x548/0x720 mm/slub.c:5545 kmemdup_noprof+0x2b/0x70 mm/util.c:138 kmemdup_noprof include/linux/fortify-string.h:715 [inline] __addrconf_sysctl_register+0xa7/0x4b0 net/ipv6/addrconf.c:7339 addrconf_sysctl_register+0x168/0x1c0 net/ipv6/addrconf.c:7405 ipv6_add_dev+0xd5f/0x1400 net/ipv6/addrconf.c:463 addrconf_notify+0x771/0x1050 net/ipv6/addrconf.c:3689 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2313 [inline] call_netdevice_notifiers net/core/dev.c:2327 [inline] register_netdevice+0x18a4/0x1eb0 net/core/dev.c:11541 veth_newlink+0x4d5/0xdc0 drivers/net/veth.c:1870 rtnl_newlink_create+0x305/0x7b0 net/core/rtnetlink.c:3996 page last free pid 5750 tgid 5750 ts 84970730053 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1418 [inline] __free_frozen_pages+0xc93/0xd90 mm/page_alloc.c:2962 __slab_free+0x274/0x2c0 mm/slub.c:5815 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4683 [inline] slab_alloc_node mm/slub.c:4996 [inline] __kmalloc_cache_noprof+0x29f/0x600 mm/slub.c:5559 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] ____ip_mc_inc_group+0x518/0xdb0 net/ipv4/igmp.c:1601 __ip_mc_inc_group net/ipv4/igmp.c:1639 [inline] ip_mc_inc_group net/ipv4/igmp.c:1645 [inline] ip_mc_up+0x115/0x2e0 net/ipv4/igmp.c:1950 inetdev_event+0xe8a/0x1610 net/ipv4/devinet.c:1632 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2313 [inline] call_netdevice_notifiers net/core/dev.c:2327 [inline] __dev_notify_flags+0x31e/0x510 net/core/dev.c:9853 rtnl_configure_link+0x2f5/0x510 net/core/rtnetlink.c:3759 rtnl_newlink_create+0x343/0x7b0 net/core/rtnetlink.c:4004 __rtnl_newlink net/core/rtnetlink.c:4125 [inline] rtnl_newlink+0x167a/0x1c30 net/core/rtnetlink.c:4242 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7159 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556 Memory state around the buggy address: ffff888031de2d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888031de2d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888031de2e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888031de2e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888031de2f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== final repro crashed as (corrupted=false): ================================================================== BUG: KASAN: slab-use-after-free in netdev_need_ops_lock include/net/netdev_lock.h:30 [inline] BUG: KASAN: slab-use-after-free in netdev_lock_ops include/net/netdev_lock.h:41 [inline] BUG: KASAN: slab-use-after-free in __ethtool_get_link_ksettings+0x230/0x250 net/ethtool/ioctl.c:463 Read of size 1 at addr ffff888031de2e09 by task kworker/0:0/9 CPU: 0 UID: 0 PID: 9 Comm: kworker/0:0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: events smc_ib_port_event_work Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 netdev_need_ops_lock include/net/netdev_lock.h:30 [inline] netdev_lock_ops include/net/netdev_lock.h:41 [inline] __ethtool_get_link_ksettings+0x230/0x250 net/ethtool/ioctl.c:463 __ethtool_get_link_ksettings+0x11f/0x250 net/ethtool/ioctl.c:464 ib_get_eth_speed+0x180/0x7f0 drivers/infiniband/core/verbs.c:2061 rxe_query_port+0x93/0x3d0 drivers/infiniband/sw/rxe/rxe_verbs.c:56 __ib_query_port drivers/infiniband/core/device.c:2304 [inline] ib_query_port+0x16e/0x830 drivers/infiniband/core/device.c:2336 smc_ib_remember_port_attr net/smc/smc_ib.c:364 [inline] smc_ib_port_event_work+0x147/0x920 net/smc/smc_ib.c:388 process_one_work kernel/workqueue.c:3396 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 9649: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5414 [inline] __kvmalloc_node_noprof+0x50f/0x820 mm/slub.c:7005 alloc_netdev_mqs+0xa9/0x12a0 net/core/dev.c:12117 rtnl_create_link+0x321/0xd70 net/core/rtnetlink.c:3804 rtnl_newlink_create+0x258/0x7b0 net/core/rtnetlink.c:3986 __rtnl_newlink net/core/rtnetlink.c:4125 [inline] rtnl_newlink+0x167a/0x1c30 net/core/rtnetlink.c:4242 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7159 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x7bd/0x940 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:800 __sock_sendmsg net/socket.c:815 [inline] __sys_sendto+0x408/0x5a0 net/socket.c:2281 __do_sys_sendto net/socket.c:2288 [inline] __se_sys_sendto net/socket.c:2284 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2284 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 1027: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2748 [inline] slab_free mm/slub.c:6499 [inline] kfree+0x1c5/0x650 mm/slub.c:6792 device_release+0xc4/0x1f0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x222/0x550 lib/kobject.c:737 netdev_run_todo+0xeee/0x1060 net/core/dev.c:11818 default_device_exit_batch+0x6d9/0x760 net/core/dev.c:13290 ops_exit_list net/core/net_namespace.c:206 [inline] ops_undo_list+0x4b4/0x8d0 net/core/net_namespace.c:253 cleanup_net+0x572/0x810 net/core/net_namespace.c:706 process_one_work kernel/workqueue.c:3396 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff888031de2000 which belongs to the cache kmalloc-cg-4k of size 4096 The buggy address is located 3593 bytes inside of freed 4096-byte region [ffff888031de2000, ffff888031de3000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x31de0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888031de1011 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b04b500 dead000000000100 dead000000000122 raw: 0000000000000000 0000000300040004 00000000f5000000 ffff888031de1011 head: 00fff00000000040 ffff88801b04b500 dead000000000100 dead000000000122 head: 0000000000000000 0000000300040004 00000000f5000000 ffff888031de1011 head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5768, tgid 5768 (syz-executor), ts 84976368773 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871 prep_new_page mm/page_alloc.c:1879 [inline] get_page_from_freelist+0x2209/0x2280 mm/page_alloc.c:3943 __alloc_frozen_pages_noprof+0x217/0x5a0 mm/page_alloc.c:5436 alloc_slab_page mm/slub.c:3347 [inline] allocate_slab+0x7d/0x620 mm/slub.c:3462 new_slab mm/slub.c:3513 [inline] refill_objects+0x2d5/0x350 mm/slub.c:7410 refill_sheaf mm/slub.c:2885 [inline] __pcs_replace_empty_main+0x2c8/0x6c0 mm/slub.c:4774 alloc_from_pcs mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:4984 [inline] __do_kmalloc_node mm/slub.c:5413 [inline] __kmalloc_node_track_caller_noprof+0x548/0x720 mm/slub.c:5545 kmemdup_noprof+0x2b/0x70 mm/util.c:138 kmemdup_noprof include/linux/fortify-string.h:715 [inline] __addrconf_sysctl_register+0xa7/0x4b0 net/ipv6/addrconf.c:7339 addrconf_sysctl_register+0x168/0x1c0 net/ipv6/addrconf.c:7405 ipv6_add_dev+0xd5f/0x1400 net/ipv6/addrconf.c:463 addrconf_notify+0x771/0x1050 net/ipv6/addrconf.c:3689 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2313 [inline] call_netdevice_notifiers net/core/dev.c:2327 [inline] register_netdevice+0x18a4/0x1eb0 net/core/dev.c:11541 veth_newlink+0x4d5/0xdc0 drivers/net/veth.c:1870 rtnl_newlink_create+0x305/0x7b0 net/core/rtnetlink.c:3996 page last free pid 5750 tgid 5750 ts 84970730053 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1418 [inline] __free_frozen_pages+0xc93/0xd90 mm/page_alloc.c:2962 __slab_free+0x274/0x2c0 mm/slub.c:5815 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4683 [inline] slab_alloc_node mm/slub.c:4996 [inline] __kmalloc_cache_noprof+0x29f/0x600 mm/slub.c:5559 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] ____ip_mc_inc_group+0x518/0xdb0 net/ipv4/igmp.c:1601 __ip_mc_inc_group net/ipv4/igmp.c:1639 [inline] ip_mc_inc_group net/ipv4/igmp.c:1645 [inline] ip_mc_up+0x115/0x2e0 net/ipv4/igmp.c:1950 inetdev_event+0xe8a/0x1610 net/ipv4/devinet.c:1632 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2313 [inline] call_netdevice_notifiers net/core/dev.c:2327 [inline] __dev_notify_flags+0x31e/0x510 net/core/dev.c:9853 rtnl_configure_link+0x2f5/0x510 net/core/rtnetlink.c:3759 rtnl_newlink_create+0x343/0x7b0 net/core/rtnetlink.c:4004 __rtnl_newlink net/core/rtnetlink.c:4125 [inline] rtnl_newlink+0x167a/0x1c30 net/core/rtnetlink.c:4242 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7159 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556 Memory state around the buggy address: ffff888031de2d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888031de2d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888031de2e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888031de2e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888031de2f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================