SSHD error: buffer_get_ret: trying to get more bytes 257 than in buffer 76

If you have run similar error in your /var/log/auth :

Jun 28 08:01:06 server sshd[2484]: error: buffer_get_ret: trying to get more bytes 257 than in buffer 76
Jun 28 08:01:06 server sshd[2484]: error: buffer_get_string_ret: buffer_get failed
Jun 28 08:01:06 server sshd[2484]: error: buffer_get_bignum2_ret: invalid bignum

Check your .ssh/authorized_keys file and make sure your key is in one line only, start with ssh-rsa following with one space and your key WITHOUT SPACE and after that one space following with comment.

ssh-rsa AAAAB3NzaC1yc2EAAAABJQAAAQEAhBJXlF6CN/Ut+VIsRGuPmumtb50/tt5j17QwNWlydvq6nXDdVpRcFwcvB+g
FeO8QBboiZ6TXmgfZPfveBO3dKqcwzDFm+MJ9RyS51+VIsRGuPmumtb50+NzDrBxP5QBLzzBgMWuWbztspV4m
PtIaXQ0cutaeLPzmCUVuMHJs7NiU0klfLmJ4vc+VIsRGuPmumtb50+OWGeb96wARPogHDpZzJ6UGRZK1ARQ/Qi
PR7b58RBJThPUnm1teMDkHS0EJdkTwpors gADrZZwraO8ZisdqnxEtrhMmcH4oLgc343MhJjjac+qRvVnUOQ== mysshcomment.

This error usually occured when you try to copying one key from another computer.