--- ../safeugid.diff	2019-10-02 13:37:13.191868203 +0200

+++ P	2019-10-02 13:36:09.036002978 +0200

@@ -0,0 +1,211 @@

+--- lib/rpmchroot.c.orig	2019-06-26 14:17:31.411985696 +0000

++++ lib/rpmchroot.c	2019-10-02 11:35:58.788024507 +0000

+@@ -126,6 +126,7 @@ int rpmChrootIn(void)

+ 

+ 	if (chdir("/") == 0 && chroot(rootState.rootDir) == 0) {

+ 	    rootState.chrootDone = 1;

++	    rpmugChroot(1);

+ 	} else {

+ 	    rpmlog(RPMLOG_ERR, _("Unable to change root directory: %m\n"));

+ 	    rc = -1;

+@@ -151,6 +152,7 @@ int rpmChrootOut(void)

+     } else if (rootState.chrootDone == 1) {

+ 	if (chroot(".") == 0 && fchdir(rootState.cwd) == 0) {

+ 	    rootState.chrootDone = 0;

++	    rpmugChroot(0);

+ 	} else {

+ 	    rpmlog(RPMLOG_ERR, _("Unable to restore root directory: %m\n"));

+ 	    rc = -1;

+--- lib/rpmug.c.orig	2019-06-26 14:17:31.418985685 +0000

++++ lib/rpmug.c	2019-10-02 11:35:58.788024507 +0000

+@@ -11,6 +11,47 @@

+ #include "lib/rpmug.h"

+ #include "debug.h"

+ 

++#if defined(__GLIBC__)

++

++static int inchroot;

++

++/*

++ * Unfortunatelly glibc caches nss/nscd data and there is no

++ * good way to flush those caches when we did a chroot(). Thus

++ * we need to parse /etc/passwd and /etc/group ourselfs.

++ */

++static int safe_lookup(const char * file, const char * name)

++{

++    FILE *fp;

++    int l;

++    char buf[4096], *p;

++

++    if (!name || !*name)

++	return -1;

++    l = strlen(name);

++    if ((fp = fopen(file, "r")) == 0)

++	return -1;

++    while ((p = fgets(buf, sizeof(buf), fp)) != 0) {

++	if (*p == '#')

++	    continue;

++	while (*p && (*p == ' ' || *p == '\t'))

++	    p++;

++	if (strncmp(p, name, l) != 0 || p[l] != ':')

++	    continue;

++	p = strchr(p + l + 1, ':');

++	if (!p)

++	    continue;

++	fclose(fp);

++	p++;

++	while (*p && (*p == ' ' || *p == '\t'))

++	    p++;

++	return atoi(p);

++    }

++    fclose(fp);

++    return -1;

++}

++#endif

++

+ /* 

+  * These really ought to use hash tables. I just made the

+  * guess that most files would be owned by root or the same person/group

+@@ -44,17 +85,28 @@ int rpmugUid(const char * thisUname, uid

+ 	    lastUnameAlloced = thisUnameLen + 10;

+ 	    lastUname = xrealloc(lastUname, lastUnameAlloced);	/* XXX memory leak */

+ 	}

+-	strcpy(lastUname, thisUname);

+ 

+-	pwent = getpwnam(thisUname);

+-	if (pwent == NULL) {

+-	    /* FIX: shrug */

+-	    endpwent();

++#if defined(__GLIBC__)

++	if (inchroot) {

++	    int uid =  safe_lookup("/etc/passwd", thisUname);

++	    if (uid < 0)

++		return -1;

++	    lastUid = uid;

++	} else

++#endif

++	{

+ 	    pwent = getpwnam(thisUname);

+-	    if (pwent == NULL) return -1;

++	    if (pwent == NULL) {

++		/* FIX: shrug */

++		endpwent();

++		pwent = getpwnam(thisUname);

++		if (pwent == NULL) return -1;

++	    }

++	    lastUid = pwent->pw_uid;

+ 	}

+ 

+-	lastUid = pwent->pw_uid;

++	strcpy(lastUname, thisUname);

++	lastUnameLen = thisUnameLen;

+     }

+ 

+     *uid = lastUid;

+@@ -87,18 +139,29 @@ int rpmugGid(const char * thisGname, gid

+ 	    lastGnameAlloced = thisGnameLen + 10;

+ 	    lastGname = xrealloc(lastGname, lastGnameAlloced);	/* XXX memory leak */

+ 	}

+-	strcpy(lastGname, thisGname);

+ 

+-	grent = getgrnam(thisGname);

+-	if (grent == NULL) {

+-	    /* FIX: shrug */

+-	    endgrent();

++#if defined(__GLIBC__)

++	if (inchroot) {

++	    int gid =  safe_lookup("/etc/group", thisGname);

++	    if (gid < 0)

++		return -1;

++	    lastGid = gid;

++	} else

++#endif

++	{

+ 	    grent = getgrnam(thisGname);

+ 	    if (grent == NULL) {

+-		return -1;

++		/* FIX: shrug */

++		endgrent();

++		grent = getgrnam(thisGname);

++		if (grent == NULL) {

++		    return -1;

++		}

+ 	    }

++	    lastGid = grent->gr_gid;

+ 	}

+-	lastGid = grent->gr_gid;

++	strcpy(lastGname, thisGname);

++	lastGnameLen = thisGnameLen;

+     }

+ 

+     *gid = lastGid;

+@@ -110,7 +173,7 @@ const char * rpmugUname(uid_t uid)

+ {

+     static uid_t lastUid = (uid_t) -1;

+     static char * lastUname = NULL;

+-    static size_t lastUnameLen = 0;

++    static size_t lastUnameAlloced = 0;

+ 

+     if (uid == (uid_t) -1) {

+ 	lastUid = (uid_t) -1;

+@@ -127,9 +190,9 @@ const char * rpmugUname(uid_t uid)

+ 

+ 	lastUid = uid;

+ 	len = strlen(pwent->pw_name);

+-	if (lastUnameLen < len + 1) {

+-	    lastUnameLen = len + 20;

+-	    lastUname = xrealloc(lastUname, lastUnameLen);

++	if (lastUnameAlloced < len + 1) {

++	    lastUnameAlloced = len + 20;

++	    lastUname = xrealloc(lastUname, lastUnameAlloced);

+ 	}

+ 	strcpy(lastUname, pwent->pw_name);

+ 

+@@ -141,7 +204,7 @@ const char * rpmugGname(gid_t gid)

+ {

+     static gid_t lastGid = (gid_t) -1;

+     static char * lastGname = NULL;

+-    static size_t lastGnameLen = 0;

++    static size_t lastGnameAlloced = 0;

+ 

+     if (gid == (gid_t) -1) {

+ 	lastGid = (gid_t) -1;

+@@ -158,9 +221,9 @@ const char * rpmugGname(gid_t gid)

+ 

+ 	lastGid = gid;

+ 	len = strlen(grent->gr_name);

+-	if (lastGnameLen < len + 1) {

+-	    lastGnameLen = len + 20;

+-	    lastGname = xrealloc(lastGname, lastGnameLen);

++	if (lastGnameAlloced < len + 1) {

++	    lastGnameAlloced = len + 20;

++	    lastGname = xrealloc(lastGname, lastGnameAlloced);

+ 	}

+ 	strcpy(lastGname, grent->gr_name);

+ 

+@@ -192,3 +255,16 @@ void rpmugFree(void)

+     rpmugUname(-1);

+     rpmugGname(-1);

+ }

++

++void rpmugChroot(int in)

++{

++    /* tell libc to drop caches / file descriptors */

++    endpwent();

++    endgrent();

++    /* drop our own caches */

++    rpmugUid(NULL, NULL);

++    rpmugGid(NULL, NULL);

++#if defined(__GLIBC__)

++    inchroot = in;

++#endif

++}

+--- lib/rpmug.h.orig	2019-06-26 14:17:31.418985685 +0000

++++ lib/rpmug.h	2019-10-02 11:35:58.788024507 +0000

+@@ -15,4 +15,6 @@ int rpmugInit(void);

+ 

+ void rpmugFree(void);

+ 

++void rpmugChroot(int in);

++

+ #endif /* _RPMUG_H */