syzbot

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BUG: KMSAN: uninit-value in p9pdu_vreadf net/9p/protocol.c:135 [inline]
BUG: KMSAN: uninit-value in p9pdu_readf+0x463f/0x4f70 net/9p/protocol.c:526
 p9pdu_vreadf net/9p/protocol.c:135 [inline]
 p9pdu_readf+0x463f/0x4f70 net/9p/protocol.c:526
 p9pdu_vreadf net/9p/protocol.c:312 [inline]
 p9pdu_readf+0x1cbe/0x4f70 net/9p/protocol.c:526
 p9_client_getattr_dotl+0x2da/0x7f0 net/9p/client.c:1768
 v9fs_mount+0xf11/0x1460 fs/9p/vfs_super.c:160
 legacy_get_tree+0x163/0x2e0 fs/fs_context.c:610
 vfs_get_tree+0xd8/0x5d0 fs/super.c:1500
 do_new_mount+0x7b5/0x16f0 fs/namespace.c:2988
 path_mount+0x1021/0x28b0 fs/namespace.c:3318
 do_mount fs/namespace.c:3331 [inline]
 __do_sys_mount fs/namespace.c:3539 [inline]
 __se_sys_mount+0x8a8/0x9d0 fs/namespace.c:3516
 __ia32_sys_mount+0x157/0x1b0 fs/namespace.c:3516
 do_syscall_32_irqs_on arch/x86/entry/common.c:114 [inline]
 __do_fast_syscall_32+0x96/0xf0 arch/x86/entry/common.c:180
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:205
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:248
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Local variable rf created at:
 __schedule+0x53/0x20a0 kernel/sched/core.c:6136
 schedule+0x269/0x350 kernel/sched/core.c:6326

CPU: 1 PID: 6099 Comm: syz-executor.4 Not tainted 5.16.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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