libpam: fix CVE-2024-10963

Upstream-Status: Backport from https://github.com/linux-pam/linux-pam/commit/940747f88c16e029b69a74e80a2e94f65cb3e628

(From OE-Core rev: 2be498fd0872d7ccbf0e9b2eb0a1d4879823c968)

Signed-off-by: Stanislav Vovk <stanislav.vovk@est.tech>
Signed-off-by: Steve Sakoman <steve@sakoman.com>

2 files changed, 266 insertions, 0 deletions

diff --git a/meta/recipes-extended/pam/libpam/CVE-2024-10963.patch b/meta/recipes-extended/pam/libpam/CVE-2024-10963.patch
new file mode 100644
index 0000000000..b79831f0e5
--- /dev/null
+++ b/meta/recipes-extended/pam/libpam/CVE-2024-10963.patch
@@ -0,0 +1,265 @@
+From f9ccee5c4c6cb0d4197b08ebeb36c1dceffe82e8 Mon Sep 17 00:00:00 2001
+From: Thorsten Kukuk <kukuk@suse.com>
+Date: Thu, 14 Nov 2024 10:27:28 +0100
+Subject: [PATCH] pam_access: rework resolving of tokens as hostname
+
+* modules/pam_access/pam_access.c: separate resolving of IP addresses
+  from hostnames. Don't resolve TTYs or display variables as hostname
+  (#834).
+  Add "nodns" option to disallow resolving of tokens as hostname.
+* modules/pam_access/pam_access.8.xml: document nodns option
+* modules/pam_access/access.conf.5.xml: document that hostnames should
+  be written as FQHN.
+
+Upstream-Status: Backport [https://github.com/linux-pam/linux-pam/commit/940747f88c16e029b69a74e80a2e94f65cb3e628]
+CVE: CVE-2024-10963
+Signed-off-by: Stanislav Vovk <stanislav.vovk@est.tech>
+---
+ modules/pam_access/access.conf.5.xml |  4 ++
+ modules/pam_access/pam_access.8.xml  | 46 ++++++++++++------
+ modules/pam_access/pam_access.c      | 72 +++++++++++++++++++++++++++-
+ 3 files changed, 105 insertions(+), 17 deletions(-)
+
+diff --git a/modules/pam_access/access.conf.5.xml b/modules/pam_access/access.conf.5.xml
+index ff1cb223..158fc7df 100644
+--- a/modules/pam_access/access.conf.5.xml
++++ b/modules/pam_access/access.conf.5.xml
+@@ -220,10 +220,14 @@
+       the fields they are ignored. However if the list separator is changed with the
+       <emphasis>listsep</emphasis> option, the spaces will become part of the actual
+       item and the line will be most probably ignored. For this reason, it is not
+       recommended to put spaces around the ':' characters.
+     </para>
++    <para>
++      Hostnames should be written as Fully-Qualified Host Name (FQHN) to avoid
++      confusion with device names or PAM service names.
++    </para>
+   </refsect1>
+ 
+   <refsect1 xml:id="access.conf-see_also">
+     <title>SEE ALSO</title>
+     <para>
+diff --git a/modules/pam_access/pam_access.8.xml b/modules/pam_access/pam_access.8.xml
+index 010e749e..1182c907 100644
+--- a/modules/pam_access/pam_access.8.xml
++++ b/modules/pam_access/pam_access.8.xml
+@@ -20,15 +20,18 @@
+     <cmdsynopsis xml:id="pam_access-cmdsynopsis" sepchar=" ">
+       <command>pam_access.so</command>
+       <arg choice="opt" rep="norepeat">
+         debug
+       </arg>
++      <arg choice="opt" rep="norepeat">
++        noaudit
++      </arg>
+       <arg choice="opt" rep="norepeat">
+         nodefgroup
+       </arg>
+       <arg choice="opt" rep="norepeat">
+-        noaudit
++        nodns
+       </arg>
+       <arg choice="opt" rep="norepeat">
+         accessfile=<replaceable>file</replaceable>
+       </arg>
+       <arg choice="opt" rep="norepeat">
+@@ -127,10 +130,37 @@
+             Do not report logins from disallowed hosts and ttys to the audit subsystem.
+           </para>
+         </listitem>
+       </varlistentry>
+ 
++      <varlistentry>
++        <term>
++          nodefgroup
++        </term>
++        <listitem>
++          <para>
++            User tokens which are not enclosed in parentheses will not be
++           matched against the group database. The backwards compatible default is
++            to try the group database match even for tokens not enclosed
++            in parentheses.
++          </para>
++        </listitem>
++      </varlistentry>
++
++      <varlistentry>
++        <term>
++          nodns
++        </term>
++        <listitem>
++          <para>
++           Do not try to resolve tokens as hostnames, only IPv4 and IPv6
++           addresses will be resolved. Which means to allow login from a
++           remote host, the IP addresses need to be specified in <filename>access.conf</filename>.
++          </para>
++        </listitem>
++      </varlistentry>
++
+       <varlistentry>
+         <term>
+           fieldsep=separators
+         </term>
+         <listitem>
+@@ -168,24 +198,10 @@
+             "Domain Admins" contain a space.
+           </para>
+         </listitem>
+       </varlistentry>
+ 
+-      <varlistentry>
+-        <term>
+-          nodefgroup
+-        </term>
+-        <listitem>
+-          <para>
+-            User tokens which are not enclosed in parentheses will not be
+-           matched against the group database. The backwards compatible default is
+-            to try the group database match even for tokens not enclosed
+-            in parentheses.
+-          </para>
+-        </listitem>
+-      </varlistentry>
+-
+     </variablelist>
+   </refsect1>
+ 
+   <refsect1 xml:id="pam_access-types">
+     <title>MODULE TYPES PROVIDED</title>
+diff --git a/modules/pam_access/pam_access.c b/modules/pam_access/pam_access.c
+index f70b7e49..d06496c3 100644
+--- a/modules/pam_access/pam_access.c
++++ b/modules/pam_access/pam_access.c
+@@ -97,10 +97,11 @@ struct login_info {
+     const char *config_file;
+     const char *hostname;
+     int debug;                         /* Print debugging messages. */
+     int only_new_group_syntax;         /* Only allow group entries of the form "(xyz)" */
+     int noaudit;                       /* Do not audit denials */
++    int nodns;                          /* Do not try to resolve tokens as hostnames */
+     const char *fs;                    /* field separator */
+     const char *sep;                   /* list-element separator */
+     int from_remote_host;               /* If PAM_RHOST was used for from */
+     struct addrinfo *res;              /* Cached DNS resolution of from */
+     int gai_rv;                                /* Cached retval of getaddrinfo */
+@@ -148,10 +149,12 @@ parse_args(pam_handle_t *pamh, struct login_info *loginfo,
+            loginfo->debug = YES;
+        } else if (strcmp (argv[i], "nodefgroup") == 0) {
+            loginfo->only_new_group_syntax = YES;
+        } else if (strcmp (argv[i], "noaudit") == 0) {
+            loginfo->noaudit = YES;
++       } else if (strcmp (argv[i], "nodns") == 0) {
++           loginfo->nodns = YES;
+        } else {
+            pam_syslog(pamh, LOG_ERR, "unrecognized option [%s]", argv[i]);
+        }
+     }
+ 
+@@ -730,11 +733,11 @@ remote_match (pam_handle_t *pamh, char *tok, struct login_info *item)
+ 
+     if (tok[0] == '.') {                       /* domain: match last fields */
+       if ((str_len = strlen(string)) > tok_len
+          && strcasecmp(tok, string + str_len - tok_len) == 0)
+        return YES;
+-    } else if (tok[tok_len - 1] == '.') {       /* internet network numbers (end with ".") */
++    } else if (tok[tok_len - 1] == '.') {       /* internet network numbers/subnet (end with ".") */
+       struct addrinfo hint;
+ 
+       memset (&hint, '\0', sizeof (hint));
+       hint.ai_flags = AI_CANONNAME;
+       hint.ai_family = AF_INET;
+@@ -805,10 +808,43 @@ string_match (pam_handle_t *pamh, const char *tok, const char *string,
+     }
+     return (NO);
+ }
+ 
+ 
++static int
++is_device (pam_handle_t *pamh, const char *tok)
++{
++  struct stat st;
++  const char *dev = "/dev/";
++  char *devname;
++
++  devname = malloc (strlen(dev) + strlen (tok) + 1);
++  if (devname == NULL) {
++      pam_syslog(pamh, LOG_ERR, "Cannot allocate memory for device name: %m");
++      /*
++       * We should return an error and abort, but pam_access has no good
++       * error handling.
++       */
++      return NO;
++  }
++
++  char *cp = stpcpy (devname, dev);
++  strcpy (cp, tok);
++
++  if (lstat(devname, &st) != 0)
++    {
++      free (devname);
++      return NO;
++    }
++  free (devname);
++
++  if (S_ISCHR(st.st_mode))
++    return YES;
++
++  return NO;
++}
++
+ /* network_netmask_match - match a string against one token
+  * where string is a hostname or ip (v4,v6) address and tok
+  * represents either a hostname, a single ip (v4,v6) address
+  * or a network/netmask
+  */
+@@ -866,14 +902,46 @@ network_netmask_match (pam_handle_t *pamh,
+        if (getaddrinfo (tok, NULL, NULL, &ai) != 0)
+          {
+            return NO;
+          }
+       }
++    else if (isipaddr(tok, NULL, NULL) == YES)
++      {
++       if (getaddrinfo (tok, NULL, NULL, &ai) != 0)
++         {
++           if (item->debug)
++             pam_syslog(pamh, LOG_DEBUG, "cannot resolve IP address \"%s\"", tok);
++
++           return NO;
++         }
++       netmask_ptr = NULL;
++      }
++    else if (item->nodns)
++      {
++       /* Only hostnames are left, which we would need to resolve via DNS */
++       return NO;
++      }
+     else
+       {
++       /* Bail out on X11 Display entries and ttys. */
++       if (tok[0] == ':')
++         {
++           if (item->debug)
++             pam_syslog (pamh, LOG_DEBUG,
++                         "network_netmask_match: tok=%s is X11 display", tok);
++           return NO;
++         }
++       if (is_device (pamh, tok))
++         {
++           if (item->debug)
++             pam_syslog (pamh, LOG_DEBUG,
++                         "network_netmask_match: tok=%s is a TTY", tok);
++           return NO;
++         }
++
+         /*
+-        * It is either an IP address or a hostname.
++        * It is most likely a hostname.
+         * Let getaddrinfo sort everything out
+         */
+        if (getaddrinfo (tok, NULL, NULL, &ai) != 0)
+          {
+            pam_syslog(pamh, LOG_ERR, "cannot resolve hostname \"%s\"", tok);
+-- 
+2.43.5
+
diff --git a/meta/recipes-extended/pam/libpam_1.5.3.bb b/meta/recipes-extended/pam/libpam_1.5.3.bb
index 815085cc82..4c27767ab1 100644
--- a/meta/recipes-extended/pam/libpam_1.5.3.bb
+++ b/meta/recipes-extended/pam/libpam_1.5.3.bb
@@ -34,6 +34,7 @@ SRC_URI = "${GITHUB_BASE_URI}/download/v${PV}/Linux-PAM-${PV}.tar.xz \
            file://CVE-2025-6020-01.patch \
            file://CVE-2025-6020-02.patch \
            file://CVE-2025-6020-03.patch \
+           file://CVE-2024-10963.patch \
            "
 
 SRC_URI[sha256sum] = "7ac4b50feee004a9fa88f1dfd2d2fa738a82896763050cd773b3c54b0a818283"