Extracting prog: 4m37.026315997s
Minimizing prog: 30m26.630976698s
Simplifying prog options: 8m38.574489752s
Extracting C: 5m15.402468408s
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:4 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:4 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 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:4 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 crashed: lost connection to test machine
suppressed program crash: lost connection to test machine
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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:4 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:4 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:4 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:4 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:4 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
a never seen crash title: KASAN: slab-use-after-free Read in __ethtool_get_link_ksettings, ignore
testing program (duration=6m0s, {Threaded:true 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:true Repeat:true RepeatTimes:0 Procs:4 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:true Repeat:true RepeatTimes:0 Procs:4 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:true Repeat:true RepeatTimes:0 Procs:4 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
validation run: crashed=false
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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 1h7m53.161583502s
repro crashed as (corrupted=false):
==================================================================
BUG: KASAN: slab-use-after-free in __ethtool_get_link_ksettings+0x5e/0x170 net/ethtool/ioctl.c:444
Read of size 8 at addr ffff88804cabc2f0 by task kworker/0:3/5773

CPU: 0 UID: 0 PID: 5773 Comm: kworker/0:3 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events smc_ib_port_event_work
Call Trace:
 <TASK>
 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
 __ethtool_get_link_ksettings+0x5e/0x170 net/ethtool/ioctl.c:444
 ib_get_eth_speed+0x180/0x800 drivers/infiniband/core/verbs.c:2055
 rxe_query_port+0x93/0x3e0 drivers/infiniband/sw/rxe/rxe_verbs.c:62
 __ib_query_port drivers/infiniband/core/device.c:2121 [inline]
 ib_query_port+0x170/0x840 drivers/infiniband/core/device.c:2153
 smc_ib_remember_port_attr net/smc/smc_ib.c:364 [inline]
 smc_ib_port_event_work+0x16f/0x940 net/smc/smc_ib.c:388
 process_one_work+0xa31/0x1980 kernel/workqueue.c:3320
 process_scheduled_works kernel/workqueue.c:3423 [inline]
 worker_thread+0xba8/0x11e0 kernel/workqueue.c:3509
 kthread+0x388/0x470 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
 </TASK>

Allocated by task 18712:
 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:5308 [inline]
 __kvmalloc_node_noprof+0x3c2/0x8e0 mm/slub.c:6873
 alloc_netdev_mqs+0xa8/0x1260 net/core/dev.c:12040
 rtnl_create_link+0x31f/0xd70 net/core/rtnetlink.c:3672
 rtnl_newlink_create+0x277/0xb70 net/core/rtnetlink.c:3854
 __rtnl_newlink net/core/rtnetlink.c:3995 [inline]
 rtnl_newlink+0x166a/0x1bb0 net/core/rtnetlink.c:4110
 rtnetlink_rcv_msg+0x7d5/0xbe0 net/core/rtnetlink.c:6996
 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2551
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x780/0x920 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1895
 sock_sendmsg_nosec+0x112/0x150 net/socket.c:797
 __sock_sendmsg net/socket.c:812 [inline]
 __sys_sendto+0x402/0x590 net/socket.c:2280
 __do_sys_sendto net/socket.c:2287 [inline]
 __se_sys_sendto net/socket.c:2283 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2283
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 13:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x46/0x50 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:2700 [inline]
 slab_free mm/slub.c:6291 [inline]
 kfree+0x1c5/0x6c0 mm/slub.c:6606
 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+0x228/0x560 lib/kobject.c:737
 netdev_run_todo+0xfb6/0x1130 net/core/dev.c:11741
 default_device_exit_batch+0x967/0x9e0 net/core/dev.c:13093
 ops_exit_list net/core/net_namespace.c:205 [inline]
 ops_undo_list+0x52b/0x940 net/core/net_namespace.c:252
 cleanup_net+0x56e/0x800 net/core/net_namespace.c:702
 process_one_work+0xa31/0x1980 kernel/workqueue.c:3320
 process_scheduled_works kernel/workqueue.c:3423 [inline]
 worker_thread+0xba8/0x11e0 kernel/workqueue.c:3509
 kthread+0x388/0x470 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 ffff88804cabc000
 which belongs to the cache kmalloc-cg-8k of size 8192
The buggy address is located 752 bytes inside of
 freed 8192-byte region [ffff88804cabc000, ffff88804cabe000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4cab8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88804caba011
flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff88813febe640 dead000000000100 dead000000000122
raw: 0000000000000000 0000400000020002 00000000f5000000 ffff88804caba011
head: 0080000000000040 ffff88813febe640 dead000000000100 dead000000000122
head: 0000000000000000 0000400000020002 00000000f5000000 ffff88804caba011
head: 0080000000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: 0000000000000000 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 0xd60c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 10783, tgid 10783 (syz-executor), ts 410216351204, free_ts 410210067530
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1861
 prep_new_page mm/page_alloc.c:1869 [inline]
 get_page_from_freelist+0x27d6/0x2850 mm/page_alloc.c:3949
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5292
 alloc_slab_page mm/slub.c:3289 [inline]
 allocate_slab+0x74/0x5e0 mm/slub.c:3404
 new_slab mm/slub.c:3447 [inline]
 refill_objects+0x33c/0x3d0 mm/slub.c:7319
 refill_sheaf mm/slub.c:2827 [inline]
 __pcs_replace_empty_main+0x373/0x720 mm/slub.c:4664
 alloc_from_pcs mm/slub.c:4762 [inline]
 slab_alloc_node mm/slub.c:4896 [inline]
 __do_kmalloc_node mm/slub.c:5307 [inline]
 __kvmalloc_node_noprof+0x6f4/0x8e0 mm/slub.c:6873
 alloc_netdev_mqs+0xa8/0x1260 net/core/dev.c:12040
 rtnl_create_link+0x31f/0xd70 net/core/rtnetlink.c:3672
 rtnl_newlink_create+0x277/0xb70 net/core/rtnetlink.c:3854
 __rtnl_newlink net/core/rtnetlink.c:3995 [inline]
 rtnl_newlink+0x166a/0x1bb0 net/core/rtnetlink.c:4110
 rtnetlink_rcv_msg+0x7d5/0xbe0 net/core/rtnetlink.c:6996
 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2551
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x780/0x920 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1895
 sock_sendmsg_nosec+0x112/0x150 net/socket.c:797
page last free pid 4977 tgid 4977 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1405 [inline]
 __free_frozen_pages+0x1075/0x11b0 mm/page_alloc.c:2946
 __slab_free+0x252/0x2a0 mm/slub.c:5653
 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:4582 [inline]
 slab_alloc_node mm/slub.c:4911 [inline]
 __kmalloc_cache_noprof+0x338/0x690 mm/slub.c:5427
 kmalloc_noprof include/linux/slab.h:950 [inline]
 kzalloc_noprof include/linux/slab.h:1188 [inline]
 kobject_uevent_env+0x28f/0x9e0 lib/kobject_uevent.c:543
 kobject_synth_uevent+0x585/0xbd0 lib/kobject_uevent.c:207
 uevent_store+0x26/0x70 drivers/base/core.c:2773
 kernfs_fop_write_iter+0x3b0/0x540 fs/kernfs/file.c:352
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x629/0xba0 fs/read_write.c:688
 ksys_write+0x156/0x270 fs/read_write.c:740
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804cabc180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88804cabc200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88804cabc280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                             ^
 ffff88804cabc300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88804cabc380: 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+0x5e/0x170 net/ethtool/ioctl.c:444
Read of size 8 at addr ffff88804cabc2f0 by task kworker/0:3/5773

CPU: 0 UID: 0 PID: 5773 Comm: kworker/0:3 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events smc_ib_port_event_work
Call Trace:
 <TASK>
 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
 __ethtool_get_link_ksettings+0x5e/0x170 net/ethtool/ioctl.c:444
 ib_get_eth_speed+0x180/0x800 drivers/infiniband/core/verbs.c:2055
 rxe_query_port+0x93/0x3e0 drivers/infiniband/sw/rxe/rxe_verbs.c:62
 __ib_query_port drivers/infiniband/core/device.c:2121 [inline]
 ib_query_port+0x170/0x840 drivers/infiniband/core/device.c:2153
 smc_ib_remember_port_attr net/smc/smc_ib.c:364 [inline]
 smc_ib_port_event_work+0x16f/0x940 net/smc/smc_ib.c:388
 process_one_work+0xa31/0x1980 kernel/workqueue.c:3320
 process_scheduled_works kernel/workqueue.c:3423 [inline]
 worker_thread+0xba8/0x11e0 kernel/workqueue.c:3509
 kthread+0x388/0x470 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
 </TASK>

Allocated by task 18712:
 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:5308 [inline]
 __kvmalloc_node_noprof+0x3c2/0x8e0 mm/slub.c:6873
 alloc_netdev_mqs+0xa8/0x1260 net/core/dev.c:12040
 rtnl_create_link+0x31f/0xd70 net/core/rtnetlink.c:3672
 rtnl_newlink_create+0x277/0xb70 net/core/rtnetlink.c:3854
 __rtnl_newlink net/core/rtnetlink.c:3995 [inline]
 rtnl_newlink+0x166a/0x1bb0 net/core/rtnetlink.c:4110
 rtnetlink_rcv_msg+0x7d5/0xbe0 net/core/rtnetlink.c:6996
 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2551
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x780/0x920 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1895
 sock_sendmsg_nosec+0x112/0x150 net/socket.c:797
 __sock_sendmsg net/socket.c:812 [inline]
 __sys_sendto+0x402/0x590 net/socket.c:2280
 __do_sys_sendto net/socket.c:2287 [inline]
 __se_sys_sendto net/socket.c:2283 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2283
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 13:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x46/0x50 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:2700 [inline]
 slab_free mm/slub.c:6291 [inline]
 kfree+0x1c5/0x6c0 mm/slub.c:6606
 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+0x228/0x560 lib/kobject.c:737
 netdev_run_todo+0xfb6/0x1130 net/core/dev.c:11741
 default_device_exit_batch+0x967/0x9e0 net/core/dev.c:13093
 ops_exit_list net/core/net_namespace.c:205 [inline]
 ops_undo_list+0x52b/0x940 net/core/net_namespace.c:252
 cleanup_net+0x56e/0x800 net/core/net_namespace.c:702
 process_one_work+0xa31/0x1980 kernel/workqueue.c:3320
 process_scheduled_works kernel/workqueue.c:3423 [inline]
 worker_thread+0xba8/0x11e0 kernel/workqueue.c:3509
 kthread+0x388/0x470 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 ffff88804cabc000
 which belongs to the cache kmalloc-cg-8k of size 8192
The buggy address is located 752 bytes inside of
 freed 8192-byte region [ffff88804cabc000, ffff88804cabe000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4cab8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88804caba011
flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff88813febe640 dead000000000100 dead000000000122
raw: 0000000000000000 0000400000020002 00000000f5000000 ffff88804caba011
head: 0080000000000040 ffff88813febe640 dead000000000100 dead000000000122
head: 0000000000000000 0000400000020002 00000000f5000000 ffff88804caba011
head: 0080000000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: 0000000000000000 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 0xd60c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 10783, tgid 10783 (syz-executor), ts 410216351204, free_ts 410210067530
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1861
 prep_new_page mm/page_alloc.c:1869 [inline]
 get_page_from_freelist+0x27d6/0x2850 mm/page_alloc.c:3949
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5292
 alloc_slab_page mm/slub.c:3289 [inline]
 allocate_slab+0x74/0x5e0 mm/slub.c:3404
 new_slab mm/slub.c:3447 [inline]
 refill_objects+0x33c/0x3d0 mm/slub.c:7319
 refill_sheaf mm/slub.c:2827 [inline]
 __pcs_replace_empty_main+0x373/0x720 mm/slub.c:4664
 alloc_from_pcs mm/slub.c:4762 [inline]
 slab_alloc_node mm/slub.c:4896 [inline]
 __do_kmalloc_node mm/slub.c:5307 [inline]
 __kvmalloc_node_noprof+0x6f4/0x8e0 mm/slub.c:6873
 alloc_netdev_mqs+0xa8/0x1260 net/core/dev.c:12040
 rtnl_create_link+0x31f/0xd70 net/core/rtnetlink.c:3672
 rtnl_newlink_create+0x277/0xb70 net/core/rtnetlink.c:3854
 __rtnl_newlink net/core/rtnetlink.c:3995 [inline]
 rtnl_newlink+0x166a/0x1bb0 net/core/rtnetlink.c:4110
 rtnetlink_rcv_msg+0x7d5/0xbe0 net/core/rtnetlink.c:6996
 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2551
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x780/0x920 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1895
 sock_sendmsg_nosec+0x112/0x150 net/socket.c:797
page last free pid 4977 tgid 4977 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1405 [inline]
 __free_frozen_pages+0x1075/0x11b0 mm/page_alloc.c:2946
 __slab_free+0x252/0x2a0 mm/slub.c:5653
 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:4582 [inline]
 slab_alloc_node mm/slub.c:4911 [inline]
 __kmalloc_cache_noprof+0x338/0x690 mm/slub.c:5427
 kmalloc_noprof include/linux/slab.h:950 [inline]
 kzalloc_noprof include/linux/slab.h:1188 [inline]
 kobject_uevent_env+0x28f/0x9e0 lib/kobject_uevent.c:543
 kobject_synth_uevent+0x585/0xbd0 lib/kobject_uevent.c:207
 uevent_store+0x26/0x70 drivers/base/core.c:2773
 kernfs_fop_write_iter+0x3b0/0x540 fs/kernfs/file.c:352
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x629/0xba0 fs/read_write.c:688
 ksys_write+0x156/0x270 fs/read_write.c:740
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804cabc180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88804cabc200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88804cabc280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                             ^
 ffff88804cabc300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88804cabc380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================