libssh2: fix error handling on quote errors

Previously it lacked the actual return. libssh.c uses the same function
name.

Verified by test 2007.

Reported-by: m777m0 on hackerone

Follow-up to 578706adde

Closes #20883

lib/vssh/libssh.c

@@ -1346,8 +1346,8 @@ static int myssh_in_SFTP_POSTQUOTE_INIT(struct Curl_easy *data,
   return SSH_NO_ERROR;
 }
 
-static int return_quote_error(struct Curl_easy *data,
-                              struct ssh_conn *sshc)
+static int quote_error(struct Curl_easy *data,
+                       struct ssh_conn *sshc)
 {
   failf(data, "Suspicious data after the command line");
   Curl_safefree(sshc->quote_path1);
@@ -1467,7 +1467,7 @@ static int myssh_in_SFTP_QUOTE(struct Curl_easy *data,
       return SSH_NO_ERROR;
     }
     if(*cp)
-      return return_quote_error(data, sshc);
+      return quote_error(data, sshc);
     sshc->quote_attrs = NULL;
     myssh_to(data, sshc, SSH_SFTP_QUOTE_STAT);
     return SSH_NO_ERROR;
@@ -1490,13 +1490,13 @@ static int myssh_in_SFTP_QUOTE(struct Curl_easy *data,
       return SSH_NO_ERROR;
     }
     if(*cp)
-      return return_quote_error(data, sshc);
+      return quote_error(data, sshc);
     myssh_to(data, sshc, SSH_SFTP_QUOTE_SYMLINK);
     return SSH_NO_ERROR;
   }
   else if(!strncmp(cmd, "mkdir ", 6)) {
     if(*cp)
-      return return_quote_error(data, sshc);
+      return quote_error(data, sshc);
     /* create directory */
     myssh_to(data, sshc, SSH_SFTP_QUOTE_MKDIR);
     return SSH_NO_ERROR;
@@ -1518,27 +1518,27 @@ static int myssh_in_SFTP_QUOTE(struct Curl_easy *data,
       return SSH_NO_ERROR;
     }
     if(*cp)
-      return return_quote_error(data, sshc);
+      return quote_error(data, sshc);
     myssh_to(data, sshc, SSH_SFTP_QUOTE_RENAME);
     return SSH_NO_ERROR;
   }
   else if(!strncmp(cmd, "rmdir ", 6)) {
     /* delete directory */
     if(*cp)
-      return return_quote_error(data, sshc);
+      return quote_error(data, sshc);
     myssh_to(data, sshc, SSH_SFTP_QUOTE_RMDIR);
     return SSH_NO_ERROR;
   }
   else if(!strncmp(cmd, "rm ", 3)) {
     if(*cp)
-      return return_quote_error(data, sshc);
+      return quote_error(data, sshc);
     myssh_to(data, sshc, SSH_SFTP_QUOTE_UNLINK);
     return SSH_NO_ERROR;
   }
 #ifdef HAS_STATVFS_SUPPORT
   else if(!strncmp(cmd, "statvfs ", 8)) {
     if(*cp)
-      return return_quote_error(data, sshc);
+      return quote_error(data, sshc);
     myssh_to(data, sshc, SSH_SFTP_QUOTE_STATVFS);
     return SSH_NO_ERROR;
   }

lib/vssh/libssh2.c

@@ -715,8 +715,8 @@ static CURLcode ssh_force_knownhost_key_type(struct Curl_easy *data,
   return result;
 }
 
-static CURLcode return_quote_error(struct Curl_easy *data,
-                                   struct ssh_conn *sshc)
+static CURLcode quote_error(struct Curl_easy *data,
+                            struct ssh_conn *sshc)
 {
   failf(data, "Suspicious data after the command line");
   Curl_safefree(sshc->quote_path1);
@@ -812,7 +812,7 @@ static CURLcode sftp_quote(struct Curl_easy *data,
       return result;
     }
     if(*cp)
-      return_quote_error(data, sshc);
+      return quote_error(data, sshc);
 
     memset(&sshp->quote_attrs, 0, sizeof(LIBSSH2_SFTP_ATTRIBUTES));
     myssh_to(data, sshc, SSH_SFTP_QUOTE_STAT);
@@ -831,13 +831,13 @@ static CURLcode sftp_quote(struct Curl_easy *data,
       return result;
     }
     if(*cp)
-      return_quote_error(data, sshc);
+      return quote_error(data, sshc);
     myssh_to(data, sshc, SSH_SFTP_QUOTE_SYMLINK);
     return result;
   }
   else if(!strncmp(cmd, "mkdir ", 6)) {
     if(*cp)
-      return_quote_error(data, sshc);
+      return quote_error(data, sshc);
     /* create directory */
     myssh_to(data, sshc, SSH_SFTP_QUOTE_MKDIR);
     return result;
@@ -854,26 +854,26 @@ static CURLcode sftp_quote(struct Curl_easy *data,
       return result;
     }
     if(*cp)
-      return_quote_error(data, sshc);
+      return quote_error(data, sshc);
     myssh_to(data, sshc, SSH_SFTP_QUOTE_RENAME);
     return result;
   }
   else if(!strncmp(cmd, "rmdir ", 6)) {
     if(*cp)
-      return_quote_error(data, sshc);
+      return quote_error(data, sshc);
     /* delete directory */
     myssh_to(data, sshc, SSH_SFTP_QUOTE_RMDIR);
     return result;
   }
   else if(!strncmp(cmd, "rm ", 3)) {
     if(*cp)
-      return_quote_error(data, sshc);
+      return quote_error(data, sshc);
     myssh_to(data, sshc, SSH_SFTP_QUOTE_UNLINK);
     return result;
   }
   else if(!strncmp(cmd, "statvfs ", 8)) {
     if(*cp)
-      return_quote_error(data, sshc);
+      return quote_error(data, sshc);
     myssh_to(data, sshc, SSH_SFTP_QUOTE_STATVFS);
     return result;
   }

tests/data/Makefile.am

@@ -243,7 +243,7 @@ test1955 test1956 test1957 test1958 test1959 test1960 test1964 \
 test1970 test1971 test1972 test1973 test1974 test1975 test1976 test1977 \
 test1978 test1979 test1980 test1981 \
 \
-test2000 test2001 test2002 test2003 test2004 test2005 test2006 \
+test2000 test2001 test2002 test2003 test2004 test2005 test2006 test2007 \
 \
                                                                test2023 \
 test2024 test2025 test2026 test2027 test2028 test2029 test2030 test2031 \

tests/data/test2007

@@ -0,0 +1,32 @@
+<?xml version="1.0" encoding="US-ASCII"?>
+<testcase>
+<info>
+<keywords>
+SFTP
+--quote
+</keywords>
+</info>
+
+# Server-side
+<reply>
+</reply>
+
+# Client-side
+<client>
+<server>
+sftp
+</server>
+<name>
+SFTP quote rmdir command with trailing junk
+</name>
+<command>
+--hostpubmd5 %SSHSRVMD5 --key %LOGDIR/server/curl_client_key --pubkey %LOGDIR/server/curl_client_key.pub -u %USER: sftp://%HOSTIP:%SSHPORT%SFTP_PWD/%LOGDIR/file%TESTNUMBER.txt -Q "mkdir /tmp/test trailing_garbage"
+</command>
+</client>
+
+<verify>
+<errorcode>
+21
+</errorcode>
+</verify>
+</testcase>