[PATCH] Validate string -> number conversion.

[Arkadiusz Miśkiewicz <arekm@xxxxxxxx>]

Make sure that numbers passed as string will fit into proper
types when doing string->uid_t/gid_t/prid_t conversion.

Signed-off-by: Arkadiusz Miśkiewicz <arekm@xxxxxxxx>
---

Fixed version.

 libxcmd/input.c |   33 +++++++++++++++++++++------------
 quota/project.c |    2 +-
 2 files changed, 22 insertions(+), 13 deletions(-)

diff --git a/libxcmd/input.c b/libxcmd/input.c
index 1bc0745..d0c4e0d 100644
--- a/libxcmd/input.c
+++ b/libxcmd/input.c
@@ -336,16 +336,19 @@ prid_from_string(
        char            *project)
 {
        fs_project_t    *prj;
-       prid_t          prid;
+       unsigned long int       prid_long;
        char            *sp;
 
        /*
         * Allow either a full numeric or a valid projectname, even
         * if it starts with a digit.
         */
-       prid = (prid_t)strtoul(project, &sp, 10);
-       if (*project != '\0' && *sp == '\0')
-               return prid;
+       prid_long = strtoul(project, &sp, 10);
+       if (*project != '\0' && *sp == '\0') {
+               if ((prid_long == ULONG_MAX && errno == ERANGE) || (prid_long > 
(prid_t)-1))
+                       return -1;
+               return (prid_t)prid_long;
+       }
        prj = getprnam(project);
        if (prj)
                return prj->pr_prid;
@@ -357,12 +360,15 @@ uid_from_string(
        char            *user)
 {
        struct passwd   *pwd;
-       uid_t           uid;
+       unsigned long int       uid_long;
        char            *sp;
 
-       uid = (uid_t)strtoul(user, &sp, 10);
-       if (sp != user)
-               return uid;
+       uid_long = strtoul(user, &sp, 10);
+       if (sp != user) {
+               if ((uid_long == ULONG_MAX && errno == ERANGE) || (uid_long > 
(uid_t)-1))
+                       return -1;
+               return (uid_t)uid_long;
+       }
        pwd = getpwnam(user);
        if (pwd)
                return pwd->pw_uid;
@@ -374,12 +380,15 @@ gid_from_string(
        char            *group)
 {
        struct group    *grp;
-       gid_t           gid;
+       unsigned long int       gid_long;
        char            *sp;
 
-       gid = (gid_t)strtoul(group, &sp, 10);
-       if (sp != group)
-               return gid;
+       gid_long = strtoul(group, &sp, 10);
+       if (sp != group) {
+               if ((gid_long == ULONG_MAX && errno == ERANGE) || (gid_long > 
(gid_t)-1))
+                       return -1;
+               return (gid_t)gid_long;
+       }
        grp = getgrnam(group);
        if (grp)
                return grp->gr_gid;
diff --git a/quota/project.c b/quota/project.c
index 1aacddd..e9baadd 100644
--- a/quota/project.c
+++ b/quota/project.c
@@ -331,7 +331,7 @@ project_f(
                prid = prid_from_string(argv[optind]);
                if (prid == -1) {
                        exitcode = 1;
-                       fprintf(stderr, _("%s - no such project in %s\n"),
+                       fprintf(stderr, _("%s - no such project in %s or 
invalid project number\n"),
                                argv[optind], projects_file);
                } else
                        project(argv[optind], type);
-- 
1.7.2.2