Extracting prog: 4m9.222636041s Minimizing prog: 30m13.694958193s Simplifying prog options: 12m33.70304545s Extracting C: 5m44.438212089s 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, &(0x7f0000000240)={0x0, 0x0, &(0x7f0000000200)={&(0x7f0000000340)={0x38, 0x1403, 0xc23, 0x70bd2a, 0x25dfdbff, "", [{{0x9, 0x2, 'syz2\x00'}, {0x8, 0x41, 'rxe\x00'}, {0x14, 0x33, 'ipvlan1\x00'}}]}, 0x38}, 0x1, 0x0, 0x0, 0x48845}, 0xc000) 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, &(0x7f0000000240)={0x0, 0x0, &(0x7f0000000200)={&(0x7f0000000340)={0x38, 0x1403, 0xc23, 0x70bd2a, 0x25dfdbff, "", [{{0x9, 0x2, 'syz2\x00'}, {0x8, 0x41, 'rxe\x00'}, {0x14, 0x33, 'ipvlan1\x00'}}]}, 0x38}, 0x1, 0x0, 0x0, 0x48845}, 0xc000) 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, &(0x7f0000000240)={0x0, 0x0, &(0x7f0000000200)={&(0x7f0000000340)={0x38, 0x1403, 0xc23, 0x70bd2a, 0x25dfdbff, "", [{{0x9, 0x2, 'syz2\x00'}, {0x8, 0x41, 'rxe\x00'}, {0x14, 0x33, 'ipvlan1\x00'}}]}, 0x38}, 0x1, 0x0, 0x0, 0x48845}, 0xc000) 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, 0xc000) 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, &(0x7f0000000240)={0x0, 0x0, 0x0, 0x1, 0x0, 0x0, 0x48845}, 0xc000) 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, &(0x7f0000000240)={0x0, 0x0, &(0x7f0000000200)={0x0}, 0x1, 0x0, 0x0, 0x48845}, 0xc000) 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, &(0x7f0000000240)={0x0, 0x0, &(0x7f0000000200)={&(0x7f0000000340)={0x38, 0x1403, 0xc23, 0x70bd2a, 0x25dfdbff, "", [{{0x9, 0x2, 'syz2\x00'}, {0x8, 0x41, 'rxe\x00'}, {0x14, 0x33, 'ipvlan1\x00'}}]}, 0x38}, 0x1, 0x0, 0x0, 0x48845}, 0xc000) 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, &(0x7f0000000240)={0x0, 0x0, &(0x7f0000000200)={&(0x7f0000000340)={0x38, 0x1403, 0xc23, 0x70bd2a, 0x25dfdbff, "", [{{0x9, 0x2, 'syz2\x00'}, {0x8, 0x41, 'rxe\x00'}, {0x14, 0x33, 'ipvlan1\x00'}}]}, 0x38}, 0x1, 0x0, 0x0, 0x48845}, 0xc000) 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, &(0x7f0000000240)={0x0, 0x0, &(0x7f0000000200)={&(0x7f0000000340)={0x38, 0x1403, 0xc23, 0x70bd2a, 0x25dfdbff, "", [{{0x9, 0x2, 'syz2\x00'}, {0x8, 0x41, 'rxe\x00'}, {0x14, 0x33, 'ipvlan1\x00'}}]}, 0x38}, 0x1, 0x0, 0x0, 0x48845}, 0xc000) 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, &(0x7f0000000240)={0x0, 0x0, &(0x7f0000000200)={&(0x7f0000000340)={0x38, 0x1403, 0xc23, 0x70bd2a, 0x25dfdbff, "", [{{0x9, 0x2, 'syz2\x00'}, {0x8, 0x41, 'rxe\x00'}, {0x14, 0x33, 'ipvlan1\x00'}}]}, 0x38}, 0x1, 0x0, 0x0, 0x48845}, 0xc000) 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, &(0x7f0000000240)={0x0, 0x0, &(0x7f0000000200)={&(0x7f0000000340)={0x38, 0x1403, 0xc23, 0x70bd2a, 0x25dfdbff, "", [{{0x9, 0x2, 'syz2\x00'}, {0x8, 0x41, 'rxe\x00'}, {0x14, 0x33, 'ipvlan1\x00'}}]}, 0x38}, 0x1, 0x0, 0x0, 0x48845}, 0xc000) program crashed: KASAN: slab-use-after-free Read in __ethtool_get_link_ksettings validation run: crashed=true reproducing took 58m46.60107787s repro crashed as (corrupted=false): ================================================================== BUG: KASAN: slab-use-after-free in __ethtool_get_link_ksettings+0x60/0x174 net/ethtool/ioctl.c:444 Read of size 8 at addr ffff0000f1ab22f0 by task kworker/0:5/10648 CPU: 0 UID: 0 PID: 10648 Comm: kworker/0:5 Not tainted syzkaller #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Workqueue: events smc_ib_port_event_work Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C) __dump_stack+0x30/0x40 lib/dump_stack.c:94 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120 print_address_description+0xb0/0x238 mm/kasan/report.c:378 print_report+0x68/0x84 mm/kasan/report.c:482 kasan_report+0x8c/0xc4 mm/kasan/report.c:595 __asan_report_load8_noabort+0x20/0x2c mm/kasan/report_generic.c:381 __ethtool_get_link_ksettings+0x60/0x174 net/ethtool/ioctl.c:444 ipvlan_ethtool_get_link_ksettings+0x48/0x58 drivers/net/ipvlan/ipvlan_main.c:413 __ethtool_get_link_ksettings+0x118/0x174 net/ethtool/ioctl.c:451 ib_get_eth_speed+0x154/0x6b0 drivers/infiniband/core/verbs.c:2055 rxe_query_port+0x98/0x36c drivers/infiniband/sw/rxe/rxe_verbs.c:62 __ib_query_port drivers/infiniband/core/device.c:2121 [inline] ib_query_port+0x168/0x754 drivers/infiniband/core/device.c:2153 smc_ib_remember_port_attr net/smc/smc_ib.c:364 [inline] smc_ib_port_event_work+0x118/0x8c4 net/smc/smc_ib.c:388 process_one_work+0x78c/0x173c kernel/workqueue.c:3302 process_scheduled_works+0xdc/0x13c kernel/workqueue.c:3385 worker_thread+0x770/0xbd0 kernel/workqueue.c:3466 kthread+0x2f0/0x3c0 kernel/kthread.c:436 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:842 Allocated by task 30128: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:78 kasan_save_alloc_info+0x44/0x54 mm/kasan/generic.c:570 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x9c/0xb4 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5295 [inline] __kvmalloc_node_noprof+0x388/0x7d0 mm/slub.c:6828 alloc_netdev_mqs+0xac/0xe60 net/core/dev.c:12026 rtnl_create_link+0x2c8/0xb94 net/core/rtnetlink.c:3671 rtnl_newlink_create+0x210/0x768 net/core/rtnetlink.c:3853 __rtnl_newlink net/core/rtnetlink.c:3994 [inline] rtnl_newlink+0xdc4/0x113c net/core/rtnetlink.c:4109 rtnetlink_rcv_msg+0x64c/0x984 net/core/rtnetlink.c:6995 netlink_rcv_skb+0x22c/0x410 net/netlink/af_netlink.c:2550 rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:7022 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x610/0x800 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x63c/0x920 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:787 [inline] __sock_sendmsg+0xc8/0x138 net/socket.c:802 __sys_sendto+0x254/0x338 net/socket.c:2265 __do_sys_sendto net/socket.c:2272 [inline] __se_sys_sendto net/socket.c:2268 [inline] __arm64_sys_sendto+0xd8/0xf8 net/socket.c:2268 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:140 el0_svc+0x60/0x25c arch/arm64/kernel/entry-common.c:723 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:742 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594 Freed by task 12: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:78 kasan_save_free_info+0x58/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x74/0xa4 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2689 [inline] slab_free mm/slub.c:6246 [inline] kfree+0x188/0x5e4 mm/slub.c:6561 kvfree+0x30/0x40 mm/slub.c:6877 netdev_release+0x88/0xb0 net/core/net-sysfs.c:2237 device_release+0xa8/0x1c8 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+0x1dc/0x4bc lib/kobject.c:737 netdev_run_todo+0xab4/0xc48 net/core/dev.c:11727 rtnl_unlock+0x14/0x20 net/core/rtnetlink.c:157 default_device_exit_batch+0x584/0x600 net/core/dev.c:13074 ops_exit_list net/core/net_namespace.c:205 [inline] ops_undo_list+0x430/0x7e4 net/core/net_namespace.c:252 cleanup_net+0x470/0x6b8 net/core/net_namespace.c:702 process_one_work+0x78c/0x173c kernel/workqueue.c:3302 process_scheduled_works+0xdc/0x13c kernel/workqueue.c:3385 worker_thread+0x770/0xbd0 kernel/workqueue.c:3466 kthread+0x2f0/0x3c0 kernel/kthread.c:436 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:842 The buggy address belongs to the object at ffff0000f1ab2000 which belongs to the cache kmalloc-cg-4k of size 4096 The buggy address is located 752 bytes inside of freed 4096-byte region [ffff0000f1ab2000, ffff0000f1ab3000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x131ab0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff0000f1ab1011 flags: 0x5ffc00000000040(head|node=0|zone=2|lastcpupid=0x7ff) page_type: f5(slab) raw: 05ffc00000000040 ffff0000c001d500 dead000000000100 dead000000000122 raw: 0000000000000000 0000200000040004 00000000f5000000 ffff0000f1ab1011 head: 05ffc00000000040 ffff0000c001d500 dead000000000100 dead000000000122 head: 0000000000000000 0000200000040004 00000000f5000000 ffff0000f1ab1011 head: 05ffc00000000003 fffffdffc3c6ac01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000f1ab2180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000f1ab2200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000f1ab2280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000f1ab2300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000f1ab2380: 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 __ethtool_get_link_ksettings+0x60/0x174 net/ethtool/ioctl.c:444 Read of size 8 at addr ffff0000f1ab22f0 by task kworker/0:5/10648 CPU: 0 UID: 0 PID: 10648 Comm: kworker/0:5 Not tainted syzkaller #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Workqueue: events smc_ib_port_event_work Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C) __dump_stack+0x30/0x40 lib/dump_stack.c:94 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120 print_address_description+0xb0/0x238 mm/kasan/report.c:378 print_report+0x68/0x84 mm/kasan/report.c:482 kasan_report+0x8c/0xc4 mm/kasan/report.c:595 __asan_report_load8_noabort+0x20/0x2c mm/kasan/report_generic.c:381 __ethtool_get_link_ksettings+0x60/0x174 net/ethtool/ioctl.c:444 ipvlan_ethtool_get_link_ksettings+0x48/0x58 drivers/net/ipvlan/ipvlan_main.c:413 __ethtool_get_link_ksettings+0x118/0x174 net/ethtool/ioctl.c:451 ib_get_eth_speed+0x154/0x6b0 drivers/infiniband/core/verbs.c:2055 rxe_query_port+0x98/0x36c drivers/infiniband/sw/rxe/rxe_verbs.c:62 __ib_query_port drivers/infiniband/core/device.c:2121 [inline] ib_query_port+0x168/0x754 drivers/infiniband/core/device.c:2153 smc_ib_remember_port_attr net/smc/smc_ib.c:364 [inline] smc_ib_port_event_work+0x118/0x8c4 net/smc/smc_ib.c:388 process_one_work+0x78c/0x173c kernel/workqueue.c:3302 process_scheduled_works+0xdc/0x13c kernel/workqueue.c:3385 worker_thread+0x770/0xbd0 kernel/workqueue.c:3466 kthread+0x2f0/0x3c0 kernel/kthread.c:436 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:842 Allocated by task 30128: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:78 kasan_save_alloc_info+0x44/0x54 mm/kasan/generic.c:570 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x9c/0xb4 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5295 [inline] __kvmalloc_node_noprof+0x388/0x7d0 mm/slub.c:6828 alloc_netdev_mqs+0xac/0xe60 net/core/dev.c:12026 rtnl_create_link+0x2c8/0xb94 net/core/rtnetlink.c:3671 rtnl_newlink_create+0x210/0x768 net/core/rtnetlink.c:3853 __rtnl_newlink net/core/rtnetlink.c:3994 [inline] rtnl_newlink+0xdc4/0x113c net/core/rtnetlink.c:4109 rtnetlink_rcv_msg+0x64c/0x984 net/core/rtnetlink.c:6995 netlink_rcv_skb+0x22c/0x410 net/netlink/af_netlink.c:2550 rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:7022 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x610/0x800 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x63c/0x920 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:787 [inline] __sock_sendmsg+0xc8/0x138 net/socket.c:802 __sys_sendto+0x254/0x338 net/socket.c:2265 __do_sys_sendto net/socket.c:2272 [inline] __se_sys_sendto net/socket.c:2268 [inline] __arm64_sys_sendto+0xd8/0xf8 net/socket.c:2268 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:140 el0_svc+0x60/0x25c arch/arm64/kernel/entry-common.c:723 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:742 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594 Freed by task 12: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:78 kasan_save_free_info+0x58/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x74/0xa4 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2689 [inline] slab_free mm/slub.c:6246 [inline] kfree+0x188/0x5e4 mm/slub.c:6561 kvfree+0x30/0x40 mm/slub.c:6877 netdev_release+0x88/0xb0 net/core/net-sysfs.c:2237 device_release+0xa8/0x1c8 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+0x1dc/0x4bc lib/kobject.c:737 netdev_run_todo+0xab4/0xc48 net/core/dev.c:11727 rtnl_unlock+0x14/0x20 net/core/rtnetlink.c:157 default_device_exit_batch+0x584/0x600 net/core/dev.c:13074 ops_exit_list net/core/net_namespace.c:205 [inline] ops_undo_list+0x430/0x7e4 net/core/net_namespace.c:252 cleanup_net+0x470/0x6b8 net/core/net_namespace.c:702 process_one_work+0x78c/0x173c kernel/workqueue.c:3302 process_scheduled_works+0xdc/0x13c kernel/workqueue.c:3385 worker_thread+0x770/0xbd0 kernel/workqueue.c:3466 kthread+0x2f0/0x3c0 kernel/kthread.c:436 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:842 The buggy address belongs to the object at ffff0000f1ab2000 which belongs to the cache kmalloc-cg-4k of size 4096 The buggy address is located 752 bytes inside of freed 4096-byte region [ffff0000f1ab2000, ffff0000f1ab3000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x131ab0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff0000f1ab1011 flags: 0x5ffc00000000040(head|node=0|zone=2|lastcpupid=0x7ff) page_type: f5(slab) raw: 05ffc00000000040 ffff0000c001d500 dead000000000100 dead000000000122 raw: 0000000000000000 0000200000040004 00000000f5000000 ffff0000f1ab1011 head: 05ffc00000000040 ffff0000c001d500 dead000000000100 dead000000000122 head: 0000000000000000 0000200000040004 00000000f5000000 ffff0000f1ab1011 head: 05ffc00000000003 fffffdffc3c6ac01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000f1ab2180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000f1ab2200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000f1ab2280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000f1ab2300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000f1ab2380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================