syzbot

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BUG: KMSAN: uninit-value in map_id_range_up_base kernel/user_namespace.c:360 [inline]
BUG: KMSAN: uninit-value in map_id_range_up kernel/user_namespace.c:391 [inline]
BUG: KMSAN: uninit-value in map_id_up kernel/user_namespace.c:406 [inline]
BUG: KMSAN: uninit-value in from_kuid kernel/user_namespace.c:444 [inline]
BUG: KMSAN: uninit-value in from_kuid_munged+0xb74/0xc90 kernel/user_namespace.c:469
 map_id_range_up_base kernel/user_namespace.c:360 [inline]
 map_id_range_up kernel/user_namespace.c:391 [inline]
 map_id_up kernel/user_namespace.c:406 [inline]
 from_kuid kernel/user_namespace.c:444 [inline]
 from_kuid_munged+0xb74/0xc90 kernel/user_namespace.c:469
 __scm_recv_common+0x233/0x910 net/core/scm.c:517
 scm_recv_unix+0x5e/0x580 net/core/scm.c:545
 __unix_dgram_recvmsg+0x14e1/0x1750 net/unix/af_unix.c:2666
 unix_dgram_recvmsg+0x112/0x180 net/unix/af_unix.c:2686
 sock_recvmsg_nosec net/socket.c:1137 [inline]
 sock_recvmsg+0x27b/0x310 net/socket.c:1159
 ____sys_recvmsg+0x193/0x620 net/socket.c:2918
 ___sys_recvmsg+0x20b/0x850 net/socket.c:2960
 __sys_recvmsg net/socket.c:2993 [inline]
 __do_sys_recvmsg net/socket.c:2999 [inline]
 __se_sys_recvmsg net/socket.c:2996 [inline]
 __x64_sys_recvmsg+0x20e/0x3d0 net/socket.c:2996
 x64_sys_call+0x35cc/0x3ea0 arch/x86/include/generated/asm/syscalls_64.h:48
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x134/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable scm created at:
 __unix_dgram_recvmsg+0x4d/0x1750 net/unix/af_unix.c:2569
 unix_dgram_recvmsg+0x112/0x180 net/unix/af_unix.c:2686

CPU: 0 UID: 0 PID: 4932 Comm: udevd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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