usermod.c: fix covscan RESOURCE_LEAK

Error: RESOURCE_LEAK (CWE-772): [#def31]
shadow-4.8.1/src/usermod.c:813: alloc_fn: Storage is returned from allocation function "__gr_dup".
shadow-4.8.1/src/usermod.c:813: var_assign: Assigning: "ngrp" = storage returned from "__gr_dup(grp)".
shadow-4.8.1/src/usermod.c:892: leaked_storage: Variable "ngrp" going out of scope leaks the storage it points to.
  890|   		}
  891|   	}
  892|-> }
  893|
  894|   #ifdef SHADOWGRP

Error: RESOURCE_LEAK (CWE-772): [#def32]
shadow-4.8.1/src/usermod.c:933: alloc_fn: Storage is returned from allocation function "__sgr_dup".
shadow-4.8.1/src/usermod.c:933: var_assign: Assigning: "nsgrp" = storage returned from "__sgr_dup(sgrp)".
shadow-4.8.1/src/usermod.c:1031: leaked_storage: Variable "nsgrp" going out of scope leaks the storage it points to.
 1029|   		}
 1030|   	}
 1031|-> }
 1032|   #endif				/* SHADOWGRP */
 1033|

Error: RESOURCE_LEAK (CWE-772): [#def34]
shadow-4.8.1/src/usermod.c:1161: alloc_fn: Storage is returned from allocation function "getgr_nam_gid".
shadow-4.8.1/src/usermod.c:1161: var_assign: Assigning: "grp" = storage returned from "getgr_nam_gid(optarg)".
shadow-4.8.1/src/usermod.c:1495: leaked_storage: Variable "grp" going out of scope leaks the storage it points to.
 1493|   	}
 1494|   #endif				/* ENABLE_SUBIDS */
 1495|-> }
 1496|
 1497|   /*

Error: RESOURCE_LEAK (CWE-772): [#def35]
shadow-4.8.1/src/usermod.c:1991: open_fn: Returning handle opened by "open". [Note: The source code implementation of the function has been overridden by a user model.]
shadow-4.8.1/src/usermod.c:1991: var_assign: Assigning: "fd" = handle returned from "open("/var/log/lastlog", 2)".
shadow-4.8.1/src/usermod.c:2000: noescape: Resource "fd" is not freed or pointed-to in "lseek".
shadow-4.8.1/src/usermod.c:2000: noescape: Resource "fd" is not freed or pointed-to in "read". [Note: The source code implementation of the function has been overridden by a builtin model.]
shadow-4.8.1/src/usermod.c:2003: noescape: Resource "fd" is not freed or pointed-to in "lseek".
shadow-4.8.1/src/usermod.c:2032: leaked_handle: Handle variable "fd" going out of scope leaks the handle.
 2030|   		}
 2031|   	}
 2032|-> }
 2033|
 2034|   /*

Error: RESOURCE_LEAK (CWE-772): [#def36]
shadow-4.8.1/src/usermod.c:2052: open_fn: Returning handle opened by "open". [Note: The source code implementation of the function has been overridden by a user model.]
shadow-4.8.1/src/usermod.c:2052: var_assign: Assigning: "fd" = handle returned from "open("/var/log/faillog", 2)".
shadow-4.8.1/src/usermod.c:2061: noescape: Resource "fd" is not freed or pointed-to in "lseek".
shadow-4.8.1/src/usermod.c:2061: noescape: Resource "fd" is not freed or pointed-to in "read". [Note: The source code implementation of the function has been overridden by a builtin model.]
shadow-4.8.1/src/usermod.c:2064: noescape: Resource "fd" is not freed or pointed-to in "lseek".
shadow-4.8.1/src/usermod.c:2092: leaked_handle: Handle variable "fd" going out of scope leaks the handle.
 2090|   		}
 2091|   	}
 2092|-> }
 2093|
 2094|   #ifndef NO_MOVE_MAILBOX

diff --git a/src/usermod.c b/src/usermod.c
index 7870ba57593f9ccc9eb9c46b542e299ccde1333b..03bb9b9de1044d28f698a739538723a0e8389be0 100644 (file)
--- a/src/usermod.c
+++ b/src/usermod.c
@@ -871,6 +871,8 @@ static void update_group (void)
                        SYSLOG ((LOG_WARN, "failed to prepare the new %s entry '%s'", gr_dbname (), ngrp->gr_name));
                        fail_exit (E_GRP_UPDATE);
                }
+
+               gr_free(ngrp);
        }
 }
 
@@ -1006,6 +1008,8 @@ static void update_gshadow (void)
                                 sgr_dbname (), nsgrp->sg_name));
                        fail_exit (E_GRP_UPDATE);
                }
+
+               free (nsgrp);
        }
 }
 #endif                         /* SHADOWGRP */
@@ -1152,6 +1156,7 @@ static void process_flags (int argc, char **argv)
                                }
                                user_newgid = grp->gr_gid;
                                gflg = true;
+                               gr_free (grp);
                                break;
                        case 'G':
                                if (get_groups (optarg) != 0) {
@@ -1995,8 +2000,7 @@ static void update_lastlog (void)
                /* Copy the old entry to its new location */
                if (   (lseek (fd, off_newuid, SEEK_SET) != off_newuid)
                    || (write (fd, &ll, sizeof ll) != (ssize_t) sizeof ll)
-                   || (fsync (fd) != 0)
-                   || (close (fd) != 0)) {
+                   || (fsync (fd) != 0)) {
                        fprintf (stderr,
                                 _("%s: failed to copy the lastlog entry of user %lu to user %lu: %s\n"),
                                 Prog, (unsigned long) user_id, (unsigned long) user_newid, strerror (errno));
@@ -2012,16 +2016,15 @@ static void update_lastlog (void)
                        memzero (&ll, sizeof (ll));
                        if (   (lseek (fd, off_newuid, SEEK_SET) != off_newuid)
                            || (write (fd, &ll, sizeof ll) != (ssize_t) sizeof ll)
-                           || (fsync (fd) != 0)
-                           || (close (fd) != 0)) {
+                           || (fsync (fd) != 0)) {
                                fprintf (stderr,
                                         _("%s: failed to copy the lastlog entry of user %lu to user %lu: %s\n"),
                                         Prog, (unsigned long) user_id, (unsigned long) user_newid, strerror (errno));
                        }
-               } else {
-                       (void) close (fd);
                }
        }
+
+       (void) close (fd);
 }
 
 /*
@@ -2056,8 +2059,7 @@ static void update_faillog (void)
                /* Copy the old entry to its new location */
                if (   (lseek (fd, off_newuid, SEEK_SET) != off_newuid)
                    || (write (fd, &fl, sizeof fl) != (ssize_t) sizeof fl)
-                   || (fsync (fd) != 0)
-                   || (close (fd) != 0)) {
+                   || (fsync (fd) != 0)) {
                        fprintf (stderr,
                                 _("%s: failed to copy the faillog entry of user %lu to user %lu: %s\n"),
                                 Prog, (unsigned long) user_id, (unsigned long) user_newid, strerror (errno));
@@ -2072,16 +2074,15 @@ static void update_faillog (void)
                        /* Reset the new uid's faillog entry */
                        memzero (&fl, sizeof (fl));
                        if (   (lseek (fd, off_newuid, SEEK_SET) != off_newuid)
-                           || (write (fd, &fl, sizeof fl) != (ssize_t) sizeof fl)
-                           || (close (fd) != 0)) {
+                           || (write (fd, &fl, sizeof fl) != (ssize_t) sizeof fl)) {
                                fprintf (stderr,
                                         _("%s: failed to copy the faillog entry of user %lu to user %lu: %s\n"),
                                         Prog, (unsigned long) user_id, (unsigned long) user_newid, strerror (errno));
                        }
-               } else {
-                       (void) close (fd);
                }
        }
+
+       (void) close (fd);
 }
 
 #ifndef NO_MOVE_MAILBOX