From 0218a737fe7b8f47d07d815e4b75648078ddc5d2 Mon Sep 17 00:00:00 2001 From: Tyler Hall Date: Mon, 14 Oct 2013 22:24:17 +0200 Subject: ssh: Handle successful SSH_USERAUTH_NONE According to the documentation for libssh2_userauth_list(), a NULL return value is not necessarily an error. You must call libssh2_userauth_authenticated() to determine if the SSH_USERAUTH_NONE request was successful. This fixes a segv when using sftp on a server that allows logins with an empty password. When NULL was interpreted as an error, it would free the session but not flag an error since the libssh2 errno would be clear. This resulted in dereferencing a NULL session pointer. Signed-off-by: Tyler Hall --- lib/ssh.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'lib/ssh.c') diff --git a/lib/ssh.c b/lib/ssh.c index c213225db..79f58bbf3 100644 --- a/lib/ssh.c +++ b/lib/ssh.c @@ -754,7 +754,13 @@ static CURLcode ssh_statemach_act(struct connectdata *conn, bool *block) curlx_uztoui(strlen(conn->user))); if(!sshc->authlist) { - if((err = libssh2_session_last_errno(sshc->ssh_session)) == + if(libssh2_userauth_authenticated(sshc->ssh_session)) { + sshc->authed = TRUE; + infof(data, "SSH user accepted with no authentication\n"); + state(conn, SSH_AUTH_DONE); + break; + } + else if((err = libssh2_session_last_errno(sshc->ssh_session)) == LIBSSH2_ERROR_EAGAIN) { rc = LIBSSH2_ERROR_EAGAIN; break; -- cgit v1.2.3