===================================================== BUG: KMSAN: uninit-value in netlink_policy_dump_start+0x137d/0x1520 net/netlink/policy.c:103 CPU: 0 PID: 16677 Comm: syz-executor.0 Not tainted 5.8.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x21c/0x280 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215 netlink_policy_dump_start+0x137d/0x1520 net/netlink/policy.c:103 ctrl_dumppolicy+0x201/0x1610 net/netlink/genetlink.c:1078 genl_lock_dumpit+0xdb/0x150 net/netlink/genetlink.c:553 netlink_dump+0xb73/0x1cb0 net/netlink/af_netlink.c:2245 __netlink_dump_start+0xcf2/0xea0 net/netlink/af_netlink.c:2353 genl_family_rcv_msg_dumpit net/netlink/genetlink.c:616 [inline] genl_family_rcv_msg net/netlink/genetlink.c:711 [inline] genl_rcv_msg+0x1245/0x18a0 net/netlink/genetlink.c:731 netlink_rcv_skb+0x6d7/0x7e0 net/netlink/af_netlink.c:2469 genl_rcv+0x63/0x80 net/netlink/genetlink.c:742 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x11c8/0x1490 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x173a/0x1840 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0xc82/0x1240 net/socket.c:2352 ___sys_sendmsg net/socket.c:2406 [inline] __sys_sendmsg+0x6d1/0x840 net/socket.c:2439 __compat_sys_sendmsg net/compat.c:466 [inline] __do_compat_sys_sendmsg net/compat.c:473 [inline] __se_compat_sys_sendmsg+0xa7/0xc0 net/compat.c:470 __ia32_compat_sys_sendmsg+0x4a/0x70 net/compat.c:470 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline] __do_fast_syscall_32+0x2af/0x480 arch/x86/entry/common.c:477 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7f1d549 Code: Bad RIP value. RSP: 002b:00000000f55170cc EFLAGS: 00000296 ORIG_RAX: 0000000000000172 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline] kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:127 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:80 slab_alloc_node mm/slub.c:2839 [inline] slab_alloc mm/slub.c:2848 [inline] __kmalloc_track_caller+0xbe8/0xe10 mm/slub.c:4447 __do_krealloc mm/slab_common.c:1673 [inline] krealloc+0x21d/0x410 mm/slab_common.c:1702 add_policy net/netlink/policy.c:49 [inline] netlink_policy_dump_start+0x111c/0x1520 net/netlink/policy.c:117 ctrl_dumppolicy+0x201/0x1610 net/netlink/genetlink.c:1078 genl_lock_dumpit+0xdb/0x150 net/netlink/genetlink.c:553 netlink_dump+0xb73/0x1cb0 net/netlink/af_netlink.c:2245 __netlink_dump_start+0xcf2/0xea0 net/netlink/af_netlink.c:2353 genl_family_rcv_msg_dumpit net/netlink/genetlink.c:616 [inline] genl_family_rcv_msg net/netlink/genetlink.c:711 [inline] genl_rcv_msg+0x1245/0x18a0 net/netlink/genetlink.c:731 netlink_rcv_skb+0x6d7/0x7e0 net/netlink/af_netlink.c:2469 genl_rcv+0x63/0x80 net/netlink/genetlink.c:742 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x11c8/0x1490 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x173a/0x1840 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0xc82/0x1240 net/socket.c:2352 ___sys_sendmsg net/socket.c:2406 [inline] __sys_sendmsg+0x6d1/0x840 net/socket.c:2439 __compat_sys_sendmsg net/compat.c:466 [inline] __do_compat_sys_sendmsg net/compat.c:473 [inline] __se_compat_sys_sendmsg+0xa7/0xc0 net/compat.c:470 __ia32_compat_sys_sendmsg+0x4a/0x70 net/compat.c:470 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline] __do_fast_syscall_32+0x2af/0x480 arch/x86/entry/common.c:477 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c =====================================================