I am facing a issue. When I try to do sudo on my terminal I get:

sudo: must be setuid root

I googled for the problem and did as the suggestions like setting permission of sudo but they were already in the required state. Cannot figure out what may be the problem. Please help.

Thanks

Output of mount:

 /dev/sda8 on / type ext4 (rw,errors=remount-ro) 

 proc on /proc type proc (rw,noexec,nosuid,nodev) 

 sysfs on /sys type sysfs (rw,noexec,nosuid,nodev) 

 none on /sys/fs/fuse/connections type fusectl (rw) 

 none on /sys/kernel/debug type debugfs (rw)

 none on /sys/kernel/security type securityfs (rw) 

 udev on /dev type devtmpfs (rw,mode=0755)

 devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620)

 tmpfs on /run type tmpfs (rw,noexec,nosuid,size=10%,mode=0755)

 none on /run/lock type tmpfs (rw,noexec,nosuid,nodev,size=5242880)

 none on /run/shm type tmpfs (rw,nosuid,nodev)

 /dev/sda6 on /home type ext4 (rw)

 /dev/sda7 on /var type ext4 (rw)

 /home/incaendo/.Private on /home/incaendo type ecryptfs (ecryptfs_check_dev_ruid,ecryptfs_cipher=aes,ecryptfs_key_bytes=16,ecryptfs_unlink_sigs,ecryptfs_sig=b746275454680798,ecryptfs_fnek_sig=2164f6a8d7aa74c7)

 gvfs-fuse-daemon on /home/incaendo/.gvfs type fuse.gvfs-fuse-daemon (rw,nosuid,nodev,user=incaendo)