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BUG: KMSAN: uninit-value in __ethtool_get_link_ksettings+0x503/0x5a0 net/ethtool/ioctl.c:444
CPU: 0 PID: 14358 Comm: syz-executor.0 Not tainted 5.12.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x24c/0x2e0 lib/dump_stack.c:120
 kmsan_report+0xfb/0x1e0 mm/kmsan/kmsan_report.c:121
 __msan_warning+0x5c/0xa0 mm/kmsan/kmsan_instr.c:197
 __ethtool_get_link_ksettings+0x503/0x5a0 net/ethtool/ioctl.c:444
 linkinfo_prepare_data+0x1e8/0x4b0 net/ethtool/linkinfo.c:37
 ethnl_default_notify+0x432/0x1030 net/ethtool/netlink.c:586
 ethtool_notify+0x259/0x520 net/ethtool/netlink.c:656
 ethtool_set_link_ksettings net/ethtool/ioctl.c:620 [inline]
 dev_ethtool+0xe228/0xe7b0 net/ethtool/ioctl.c:2842
 dev_ioctl+0x5a3/0x1260 net/core/dev_ioctl.c:440
 sock_do_ioctl+0x477/0x700 net/socket.c:1062
 sock_ioctl+0x997/0xef0 net/socket.c:1179
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl+0x311/0x4d0 fs/ioctl.c:739
 __x64_sys_ioctl+0x4a/0x70 fs/ioctl.c:739
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665d9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fefec2fa188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665d9
RDX: 0000000020000080 RSI: 0000000000008946 RDI: 0000000000000003
RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80
R13: 0000000000a9fb1f R14: 00007fefec2fa300 R15: 0000000000022000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:120 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:288
 kmsan_memcpy_memmove_metadata+0x25e/0x2d0 mm/kmsan/kmsan.c:225
 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:245
 __msan_memcpy+0x46/0x60 mm/kmsan/kmsan_instr.c:110
 tun_get_link_ksettings+0x7c/0xb0 drivers/net/tun.c:3418
 __ethtool_get_link_ksettings+0x204/0x5a0 net/ethtool/ioctl.c:440
 linkinfo_prepare_data+0x1e8/0x4b0 net/ethtool/linkinfo.c:37
 ethnl_default_notify+0x432/0x1030 net/ethtool/netlink.c:586
 ethtool_notify+0x259/0x520 net/ethtool/netlink.c:656
 ethtool_set_link_ksettings net/ethtool/ioctl.c:620 [inline]
 dev_ethtool+0xe228/0xe7b0 net/ethtool/ioctl.c:2842
 dev_ioctl+0x5a3/0x1260 net/core/dev_ioctl.c:440
 sock_do_ioctl+0x477/0x700 net/socket.c:1062
 sock_ioctl+0x997/0xef0 net/socket.c:1179
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl+0x311/0x4d0 fs/ioctl.c:739
 __x64_sys_ioctl+0x4a/0x70 fs/ioctl.c:739
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:120 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:288
 kmsan_memcpy_memmove_metadata+0x25e/0x2d0 mm/kmsan/kmsan.c:225
 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:245
 __msan_memcpy+0x46/0x60 mm/kmsan/kmsan_instr.c:110
 tun_set_link_ksettings+0x7e/0xb0 drivers/net/tun.c:3427
 ethtool_set_link_ksettings net/ethtool/ioctl.c:618 [inline]
 dev_ethtool+0xe1a2/0xe7b0 net/ethtool/ioctl.c:2842
 dev_ioctl+0x5a3/0x1260 net/core/dev_ioctl.c:440
 sock_do_ioctl+0x477/0x700 net/socket.c:1062
 sock_ioctl+0x997/0xef0 net/socket.c:1179
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl+0x311/0x4d0 fs/ioctl.c:739
 __x64_sys_ioctl+0x4a/0x70 fs/ioctl.c:739
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Local variable ----link_ksettings.i893@dev_ethtool created at:
 ethtool_set_link_ksettings net/ethtool/ioctl.c:586 [inline]
 dev_ethtool+0x3cdc/0xe7b0 net/ethtool/ioctl.c:2842
 ethtool_set_link_ksettings net/ethtool/ioctl.c:586 [inline]
 dev_ethtool+0x3cdc/0xe7b0 net/ethtool/ioctl.c:2842
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