CIFS mounts with extended options containing space lead to warning during umount

Issue

When using extended option in the CIFS mounts, with space in them, umount throws warnings :

[root@cifs-client ~]# umount /any/fs/
[mntent]: line 34 in /proc/mounts is bad
[mntent]: line 35 in /proc/mounts is bad
[mntent]: line 36 in /proc/mounts is bad
[mntent]: line 37 in /proc/mounts is bad
[mntent]: line 38 in /proc/mounts is bad; rest of file ignored

The lines pointed as bad, extracted from /proc/mounts, are as such :

//CIFS-server/share/ /mnt/cifs cifs [...],prepath=\some path\,[...] 0 0
//CIFS-server/share/ /mnt/cifs cifs [...],unc=\some path\,[...] 0 0