===================================================== BUG: KMSAN: uninit-value in __ethtool_get_link_ksettings+0x503/0x5a0 net/ethtool/ioctl.c:444 CPU: 1 PID: 2131 Comm: syz-executor.4 Tainted: G W 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:00007efc9076d188 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: 00007efc9076d300 R15: 0000000000022000 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline] kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:289 kmsan_memcpy_memmove_metadata+0x25e/0x2d0 mm/kmsan/kmsan.c:226 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:246 __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:121 [inline] kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:289 kmsan_memcpy_memmove_metadata+0x25e/0x2d0 mm/kmsan/kmsan.c:226 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:246 __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 =====================================================