[7615] in Athena Bugs
NeXT Mach 2.1: /bin/login environment handling code
daemon@ATHENA.MIT.EDU (Mark W. Eichin)
Sat Jun 1 13:15:47 1991
Date: Sat, 1 Jun 91 13:15:27 EDT
From: "Mark W. Eichin" <eichin@MIT.EDU>
To: bugs@MIT.EDU
Cc: erikkay@MIT.EDU
System type, version: NeXT Mach 2.1
System name: milo.mit.edu
What's wrong:
1) /source/athena/bin/login/login.c fails to copy a NULL into
the end of the copy of the environment that it makes. This breaks the
NeXT in particular because the space used by the copy of environ
happens to fall into a block that was freed by something else, and is
thus not already zeroed.
2) things which are in string.h and other standard headers
should not be *incorrectly* declared in the source.
3) setenv takes three arguments - it should be called with
three... particularly when setting KRB_ENVIRON.
What should have happened:
The following parts of a diff should be applied... your line
numbers may vary since I elided irrelevant sections. The pieces below
correspond to 2, 1, and 3 above.
The fix to (1) has the advantage of being more readable than
the existing code, as well as being correct; it is the patch that
matters particularly.
_Mark_ <eichin@athena.mit.edu>
MIT Student Information Processing Board
*** /tmp/login.c Sat Jun 1 10:38:06 1991
--- /source/athena/bin/login/login.c Thu Mar 7 13:48:56 1991
***************
*** 182,188 ****
struct passwd *pwd;
struct passwd *hes_getpwnam();
! /* char *strcat(), *rindex(), *index(), *malloc(), *realloc(); */
int timedout();
char *ttyname();
char *crypt();
--- 184,190 ----
struct passwd *pwd;
struct passwd *hes_getpwnam();
! char *strcat(), *rindex(), *index(), *malloc(), *realloc();
int timedout();
char *ttyname();
char *crypt();
***************
*** 382,395 ****
while (environ[i] != NULL)
i++;
envnew = (char **) malloc(sizeof (char *) * (i + 1));
! for (j=0, i=0; environ[i] == 0; i++, j++) {
#ifdef _I386
if(strncmp(environ[i], "INIT", 4) == 0) continue;
#endif
! envnew[j] = environ[i];
}
- envnew[j] = environ[i]; /* == 0 */
environ = envnew;
t = 0;
--- 383,396 ----
while (environ[i] != NULL)
i++;
envnew = (char **) malloc(sizeof (char *) * (i + 1));
! for (j=0; i >= 0; i--) {
! if(!environ[i]) continue;
#ifdef _I386
if(strncmp(environ[i], "INIT", 4) == 0) continue;
#endif
! envnew[j++] = environ[i];
}
environ = envnew;
t = 0;
***************
*** 453,459 ****
strncat(tkfile, rindex(ttyn, '/')+1,
sizeof(tkfile) - strlen(tkfile));
(void) unlink (tkfile);
! setenv(KRB_ENVIRON, tkfile, 1);
setpriority(PRIO_PROCESS, 0, -4);
pp = getlongpass("Password:");
--- 454,460 ----
strncat(tkfile, rindex(ttyn, '/')+1,
sizeof(tkfile) - strlen(tkfile));
(void) unlink (tkfile);
! setenv(KRB_ENVIRON, tkfile);
setpriority(PRIO_PROCESS, 0, -4);
pp = getlongpass("Password:");
