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lib/pam_pass_non_interactive.c, src/{chfn,chsh,newgrp,passwd}.c: Don't log user-provided strings #1627

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lib/pam_pass_non_interactive.c, src/{chfn,chsh,newgrp,passwd}.c: Don't log user-provided strings #1627

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8 changes: 4 additions & 4 deletions lib/pam_pass_non_interactive.c
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Original file line number Diff line number Diff line change
Expand Up @@ -126,18 +126,18 @@ int do_pam_passwd_non_interactive (const char *pam_service,
ret = pam_start (pam_service, username, &non_interactive_pam_conv, &pamh);
if (ret != PAM_SUCCESS) {
fprintf (log_get_logfd(),
_("%s: (user %s) pam_start failure %d\n"),
log_get_progname(), username, ret);
_("%s: pam_start failure %d\n"),
log_get_progname(), ret);
return 1;
}

non_interactive_password = password;
ret = pam_chauthtok (pamh, 0);
if (ret != PAM_SUCCESS) {
fprintf (log_get_logfd(),
_("%s: (user %s) pam_chauthtok() failed, error:\n"
_("%s: pam_chauthtok() failed, error:\n"
"%s\n"),
log_get_progname(), username, pam_strerror (pamh, ret));
log_get_progname(), pam_strerror (pamh, ret));
}

(void) pam_end (pamh, PAM_SUCCESS);
Expand Down
17 changes: 5 additions & 12 deletions src/chfn.c
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Original file line number Diff line number Diff line change
Expand Up @@ -19,7 +19,6 @@
#include <sys/types.h>
#include <getopt.h>

#include "chkname.h"
#include "defines.h"
/*@-exitarg@*/
#include "exitcodes.h"
Expand Down Expand Up @@ -434,8 +433,7 @@ static void update_gecos(const char *user, char *gecos, const struct option_flag
pw = pw_locate (user);
if (NULL == pw) {
fprintf (stderr,
_("%s: user '%s' does not exist in %s\n"),
Prog, user, pw_dbname ());
_("%s: user does not exist in %s\n"), Prog, pw_dbname());
fail_exit (E_NOPERM, process_selinux);
}

Expand Down Expand Up @@ -604,15 +602,10 @@ int main (int argc, char **argv)
* name, or the name getlogin() returns.
*/
if (optind < argc) {
if (!is_valid_user_name (argv[optind])) {
fprintf (stderr, _("%s: Provided user name is not a valid name\n"), Prog);
fail_exit (E_NOPERM, process_selinux);
}
user = argv[optind];
pw = xgetpwnam (user);
if (NULL == pw) {
fprintf (stderr, _("%s: user '%s' does not exist\n"), Prog,
user);
fprintf(stderr, _("%s: user does not exist\n"), Prog);
fail_exit (E_NOPERM, process_selinux);
}
} else {
Expand Down Expand Up @@ -641,7 +634,7 @@ int main (int argc, char **argv)
* user interactively change them.
*/
if (!fflg && !rflg && !wflg && !hflg && !oflg) {
printf (_("Changing the user information for %s\n"), user);
printf (_("Changing information for user %ju\n"), (uintmax_t) pw->pw_uid);
new_fields ();
}

Expand All @@ -661,14 +654,14 @@ int main (int argc, char **argv)
p = seprintf(p, e, ",%s", slop);

if (p == e || p == NULL) {
fprintf (stderr, _("%s: fields too long\n"), Prog);
fprintf(stderr, _("%s: fields too long\n"), Prog);
fail_exit (E_NOPERM, process_selinux);
}

/* Rewrite the user's gecos in the passwd file */
update_gecos (user, new_gecos, &flags);

SYSLOG(LOG_INFO, "changed user '%s' information", user);
SYSLOG(LOG_INFO, "changed user %ju information", (uintmax_t) pw->pw_uid);

nscd_flush_cache ("passwd");
sssd_flush_cache (SSSD_DB_PASSWD);
Expand Down
15 changes: 4 additions & 11 deletions src/chsh.c
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Original file line number Diff line number Diff line change
Expand Up @@ -17,7 +17,6 @@
#include <stdio.h>
#include <sys/types.h>

#include "chkname.h"
#include "defines.h"
/*@-exitarg@*/
#include "exitcodes.h"
Expand Down Expand Up @@ -413,8 +412,7 @@ static void update_shell (const char *user, char *newshell, const struct option_
pw = pw_locate (user);
if (NULL == pw) {
fprintf (stderr,
_("%s: user '%s' does not exist in %s\n"),
Prog, user, pw_dbname ());
_("%s: user does not exist in %s\n"), Prog, pw_dbname());
fail_exit (1, process_selinux);
}

Expand Down Expand Up @@ -493,15 +491,10 @@ int main (int argc, char **argv)
* name, or the name getlogin() returns.
*/
if (optind < argc) {
if (!is_valid_user_name (argv[optind])) {
fprintf (stderr, _("%s: Provided user name is not a valid name\n"), Prog);
fail_exit (1, process_selinux);
}
user = argv[optind];
pw = xgetpwnam (user);
if (NULL == pw) {
fprintf (stderr,
_("%s: user '%s' does not exist\n"), Prog, user);
fprintf(stderr, _("%s: user does not exist\n"), Prog);
fail_exit (1, process_selinux);
}
} else {
Expand Down Expand Up @@ -532,7 +525,7 @@ int main (int argc, char **argv)
* interactively change it.
*/
if (!sflg) {
printf (_("Changing the login shell for %s\n"), user);
printf(_("Changing the login shell for %ju\n"), (uintmax_t) pw->pw_uid);
new_fields ();
}

Expand Down Expand Up @@ -571,7 +564,7 @@ int main (int argc, char **argv)

update_shell (user, loginsh, &flags);

SYSLOG(LOG_INFO, "changed user '%s' shell to '%s'", user, loginsh);
SYSLOG(LOG_INFO, "changed user %ju shell to '%s'", (uintmax_t) pw->pw_uid, loginsh);

nscd_flush_cache ("passwd");
sssd_flush_cache (SSSD_DB_PASSWD);
Expand Down
82 changes: 23 additions & 59 deletions src/newgrp.c
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Original file line number Diff line number Diff line change
Expand Up @@ -19,7 +19,6 @@
#include "agetpass.h"
#include "alloc/malloc.h"
#include "alloc/realloc.h"
#include "chkname.h"
#include "defines.h"
/*@-exitarg@*/
#include "exitcodes.h"
Expand Down Expand Up @@ -60,10 +59,8 @@

/* local function prototypes */
static void usage (void);
static void check_perms (const struct group *grp,
struct passwd *pwd,
const char *groupname);
static void syslog_sg (const char *name, const char *group);
static void check_perms(const struct group *grp, struct passwd *pwd);
static void syslog_sg(const char *name, gid_t group);

/*
* usage - print command usage message
Expand Down Expand Up @@ -125,9 +122,8 @@
*
* It will not return if the user could not be authenticated.
*/
static void check_perms (const struct group *grp,
struct passwd *pwd,
const char *groupname)
static void
check_perms(const struct group *grp, struct passwd *pwd)
{
bool needspasswd = false;
struct spwd *spwd;
Expand Down Expand Up @@ -192,8 +188,8 @@
_("%s: failed to crypt password with previous salt: %s\n"),
Prog, strerrno());
SYSLOG(LOG_INFO,
"Failed to crypt password with previous salt of group '%s'",
groupname);
"Failed to crypt password with previous salt of group %ju",
(uintmax_t) grp->gr_gid);

Check warning

Code scanning / CodeQL

Potential exposure of sensitive system data to an unauthorized control sphere Medium

This operation potentially exposes sensitive system data from
*call to getgrnam
Loading
.
This operation potentially exposes sensitive system data from
*call to getgrent
Loading
.

@alejandro-colomar alejandro-colomar May 19, 2026 •
edited
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/etc/group (which is what getgrnam(3) reads) is world-readable. How is this supposed to be sensitive?

goto failure;
}

Expand All @@ -206,8 +202,8 @@
audit_buf, NULL, getuid (), SHADOW_AUDIT_FAILURE);
#endif
SYSLOG(LOG_INFO,
"Invalid password for group '%s' from '%s'",
groupname, pwd->pw_name);
"Invalid password for group %ju from '%s'",
(uintmax_t) grp->gr_gid, pwd->pw_name);

Check warning

Code scanning / CodeQL

Potential exposure of sensitive system data to an unauthorized control sphere Medium

This operation potentially exposes sensitive system data from
*call to getgrnam
Loading
.
This operation potentially exposes sensitive system data from
*call to getgrent
Loading
.
Comment thread
alejandro-colomar marked this conversation as resolved.
Dismissed
(void) sleep (1);
(void) fputs (_("Invalid password.\n"), stderr);
goto failure;
Expand Down Expand Up @@ -236,7 +232,8 @@
* The logout will also be logged when the user will quit the
* sg/newgrp session.
*/
static void syslog_sg (const char *name, const char *group)
static void
syslog_sg(const char *name, gid_t group)
{
const char *loginname = getlogin ();
const char *tty = ttyname (0);
Expand All @@ -259,8 +256,8 @@
}
tty = strprefix(tty, "/dev/") ?: tty;

SYSLOG(LOG_INFO, "user '%s' (login '%s' on %s) switched to group '%s'",
name, loginname, tty, group);
SYSLOG(LOG_INFO, "user '%s' (login '%s' on %s) switched to group %ju",
name, loginname, tty, (uintmax_t) group);
#ifdef USE_PAM
/*
* We want to fork and exec the new shell in the child, leaving the
Expand Down Expand Up @@ -298,15 +295,9 @@
fprintf (stderr, _("%s: failure forking: %s\n"),
is_newgrp ? "newgrp" : "sg", strerrno());
#ifdef WITH_AUDIT
if (group) {
audit_logger_with_group(AUDIT_CHGRP_ID, "changing", NULL,
getuid(), "new_group", group,
SHADOW_AUDIT_FAILURE);
} else {
audit_logger (AUDIT_CHGRP_ID,
"changing", NULL, getuid(),
SHADOW_AUDIT_FAILURE);
}
audit_logger(AUDIT_CHGRP_ID,
"changing", NULL, getuid(),
SHADOW_AUDIT_FAILURE);
#endif
exit (EXIT_FAILURE);
} else if (child != 0) {
Expand Down Expand Up @@ -480,12 +471,6 @@
* not "newgrp".
*/
if ((argc > 0) && (argv[0][0] != '-')) {
if (!is_valid_group_name (argv[0])) {
fprintf (
stderr, _("%s: provided group is not a valid group name\n"),
Prog);
goto failure;
}
group = argv[0];
argc--;
argv++;
Expand Down Expand Up @@ -516,12 +501,6 @@
usage ();
goto failure;
} else if (argv[0] != NULL) {
if (!is_valid_group_name (argv[0])) {
fprintf (
stderr, _("%s: provided group is not a valid group name\n"),
Prog);
goto failure;
}
group = argv[0];
} else {
/*
Expand Down Expand Up @@ -555,13 +534,8 @@
if (gids == NULL) {
perror("agetgroups");
#ifdef WITH_AUDIT
if (group) {
audit_logger_with_group(AUDIT_CHGRP_ID, "changing", NULL, getuid(),
"new_group", group, SHADOW_AUDIT_FAILURE);
} else {
audit_logger(AUDIT_CHGRP_ID,
"changing", NULL, getuid(), SHADOW_AUDIT_FAILURE);
}
audit_logger(AUDIT_CHGRP_ID,
"changing", NULL, getuid(), SHADOW_AUDIT_FAILURE);
#endif
exit(EXIT_FAILURE);
}
Expand Down Expand Up @@ -608,7 +582,7 @@
*/
grp = getgrnam (group); /* local, no need for xgetgrnam */
if (NULL == grp) {
fprintf (stderr, _("%s: group '%s' does not exist\n"), Prog, group);
fprintf(stderr, _("%s: group does not exist\n"), Prog);
goto failure;
}

Expand Down Expand Up @@ -645,19 +619,16 @@
}
#endif

/*
* Check if the user is allowed to access this group.
*/
if (!is_member) {
check_perms (grp, pwd, group);
}
// Check if the user is allowed to access this group.
if (!is_member)
check_perms(grp, pwd);

/*
* all successful validations pass through this point. The group id
* will be set, and the group added to the concurrent groupset.
*/
if (getdef_bool ("SYSLOG_SG_ENAB")) {
syslog_sg (name, group);
syslog_sg (name, grp->gr_gid);

Check warning

Code scanning / CodeQL

Potential exposure of sensitive system data to an unauthorized control sphere Medium

This operation potentially exposes sensitive system data from
*call to getgrnam
Loading
.
This operation potentially exposes sensitive system data from
*call to getgrent
Loading
.
Comment thread
alejandro-colomar marked this conversation as resolved.
Dismissed
}

gid = grp->gr_gid;
Expand Down Expand Up @@ -814,14 +785,7 @@
*/
closelog ();
#ifdef WITH_AUDIT
if (NULL != group) {
audit_logger_with_group(AUDIT_CHGRP_ID, "changing", NULL,
getuid(), "new_group", group,
SHADOW_AUDIT_FAILURE);
} else {
audit_logger (AUDIT_CHGRP_ID,
"changing", NULL, getuid (), 0);
}
audit_logger(AUDIT_CHGRP_ID, "changing", NULL, getuid(), 0);
#endif
exit (EXIT_FAILURE);
}
Expand Down
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