cifs: Fix uninitialized memory read for smb311 posix symlink create

stable inclusion
from stable-v5.10.164
commit afb6063aa89f78bcecdb3264604ce8def499e186
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7T7G4

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=afb6063aa89f78bcecdb3264604ce8def499e186



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commit a152d05a upstream.

If smb311 posix is enabled, we send the intended mode for file
creation in the posix create context. Instead of using what's there on
the stack, create the mfsymlink file with 0644.

Fixes: ce558b0e ("smb3: Add posix create context for smb3.11 posix mounts")
Cc: stable@vger.kernel.org
Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Tom Talpey <tom@talpey.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>