small bug un start-stop-daemon

[Rapsys|Phoenix <rapsys@free.fr>]

I have notice a case where start-stop daemon is blocking what should work.

I have to start a service called for example : dangerous

So i build a chroot in something like /var/chroot/dangerous

Then I build the tree :
dangerous
|-- bin
|   |-- false
|   `-- dangerous
|-- etc
|   |-- resolv.conf
|   `-- dangerous
|       |-- dbconfig
|       |-- logs
|       |   `-- net_out.log
|       |-- plugins
|       |   `-- libluaplugin.so
|       |-- scripts
|       |   |-- start.lua
|       |   |-- sometext.txt
|       `-- triggers
|           |-- happy
|           |-- linux
|           |-- lol
|           |-- moon
|           |-- house
|           |-- mouse
|           `-- wazzup
|-- lib
|   |-- ld-linux.so.2
|   |-- libGeoIP.so.1
|   |-- libc.so.6
|   |-- libcrypt.so.1
|   |-- libcrypto.so.0.9.7
|   |-- libdl.so.2
|   |-- libgcc_s.so.1
|   |-- liblua50.so.5.0
|   |-- liblualib50.so.5.0
|   |-- libluasocket.so.2.0
|   |-- libm.so.6
|   |-- libmysqlclient.so.12
|   |-- libnsl.so.1
|   |-- libnss_dns.so.2
|   |-- libpcre.so.3
|   |-- libpthread.so.0
|   |-- libresolv.so.2
|   |-- libssl.so.0.9.7
|   |-- libstdc++.so.5
|   |-- libverlihub.so.0
|   |-- libvhapi.so.0
|   `-- libz.so.1
`-- usr
    `-- share
        |-- GeoIP
        |   `-- GeoIP.dat
        `-- lua50
            `-- luasocket.lua

Then I try to start my program with a :
start-stop-daemon --start --chroot /var/chroot/dangerous -c 
verlihub:nogroup --exec /bin/dangerous

And I get a start-stop-daemon: stat /bin/dangerous: No such file or 
directory

It'a a few stupid no ?
I strace it ans see that the check if binary exist is done before the 
chroot and it will never works if the binary is not present at same 
place in the system...

I made a small change, if it could be included in next release of dpkg 
it would be great

--- utils/start-stop-daemon.c.bak       2004-11-11 04:16:35.000000000 +0100
+++ utils/start-stop-daemon.c   2005-07-17 17:27:43.633164200 +0200
@@ -1156,8 +1156,10 @@ main(int argc, char **argv)
        argc -= optind;
        argv += optind;

-       if (execname && stat(execname, &exec_stat))
-               fatal("stat %s: %s", execname, strerror(errno));
+       if (changeroot == NULL) {
+               if (execname && stat(execname, &exec_stat))
+                       fatal("stat %s: %s", execname, strerror(errno));
+       }

        if (userspec && sscanf(userspec, "%d", &user_id) != 1) {
                struct passwd *pw;
@@ -1259,6 +1261,8 @@ main(int argc, char **argv)
                        fatal("Unable to chdir() to %s", changeroot);
                if (chroot(changeroot) < 0)
                        fatal("Unable to chroot() to %s", changeroot);
+               if (execname && stat(execname, &exec_stat))
+                       fatal("stat %s: %s", execname, strerror(errno));
        }
        if (chdir(changedir) < 0)
                fatal("Unable to chdir() to %s", changedir);


ps : I don't wan't to try braking my sarge by upgrading my version of 
dpkg to a personal one, so if an updated package with could be avaible 
on (even if) an unofficial mirror I would be happy...

ps2 : maybe a nocheck option that avoid check of process and so on could 
avoid such trouble in future...