Carl Shapiro pushed to branch master at cmucl / cmucl

Commits:

• 06958230
  by Carl Shapiro at 2024-04-25T12:45:59-07:00

  Fix the retry limit for resizing password entry buffer
  
  The previous version checked that the buffer had not exceeded the
  limit of 1MiB after the buffer was resized.  In otherwords, the buffer
  is allowed to grow past the limit before the retry loop is exited.
  
  This change moves the check of the buffer size before the allocation
  occurs.  Now, the retry loop is exited before the buffer would grow
  past the limit.
  

• 520213dd
  by Carl Shapiro at 2024-04-26T02:00:30+00:00

  Merge branch 'retry-limit' into 'master'
  
  Fix the retry limit for resizing password entry buffer
  
  See merge request cmucl/cmucl!212

1 changed file:

• src/lisp/os-common.c

Changes:

      * Keep trying with larger buffers until a maximum is reached.  We

      * assume (1 << 20) is large enough for any OS.

      */

-    while (size <= (1 << 20)) {

-        switch (getpwuid_r(sb.st_uid, &pwd, buffer, size, &ppwd)) {

-          case 0:

-              /* Success, though we might not have a matching entry */

-              result = (ppwd == NULL) ? NULL : strdup(pwd.pw_name);

-              goto exit;

-          case ERANGE:

-              /* Buffer is too small, double its size and try again */

-              size *= 2;

-              if ((buffer = realloc(obuffer, size)) == NULL) {

-                  goto exit;

-              }

-	      obuffer = buffer;

-              continue;

-          default:

-              /* All other errors */

-              goto exit;

-        }

+again:

+    switch (getpwuid_r(sb.st_uid, &pwd, buffer, size, &ppwd)) {

+      case 0:

+	  /* Success, though we might not have a matching entry */

+	  result = (ppwd == NULL) ? NULL : strdup(pwd.pw_name);

+	  break;

+      case ERANGE:

+	  /* Buffer is too small, double its size and try again */

+	  size *= 2;

+	  if (size > (1 << 20)) {

+	      break;

+	  }

+	  if ((buffer = realloc(obuffer, size)) == NULL) {

+	      break;

+	  }

+	  obuffer = buffer;

+	  goto again;

+      default:

+	/* All other errors */

+	break;

     }

-exit:

     free(obuffer);

     return result;