| From: Emanuele Rocca <ema@linux.it> |
| To: Debian Bug Tracking System <submit@bugs.debian.org> |
| Subject: ppp: Buffer overflow in radius plugin |
| Date: Sun, 12 Apr 2015 14:20:02 +0200 |
| Package: ppp |
| Version: 2.4.6-3 |
| Severity: important |
| Tags: patch |
| |
| On systems with more than 65535 processes running, pppd aborts when |
| sending a "start" accounting message to the RADIUS server because of a |
| buffer overflow in rc_mksid. |
| |
| The process id is used in rc_mksid to generate a pseudo-unique string, |
| assuming that the hex representation of the pid will be at most 4 |
| characters (FFFF). __sprintf_chk(), used when compiling with |
| optimization levels greater than 0 and FORTIFY_SOURCE, detects the |
| buffer overflow and makes pppd crash. |
| |
| The following patch fixes the problem. |
| |
| --- ppp-2.4.6.orig/pppd/plugins/radius/util.c |
| +++ ppp-2.4.6/pppd/plugins/radius/util.c |
| @@ -77,7 +77,7 @@ rc_mksid (void) |
| static unsigned short int cnt = 0; |
| sprintf (buf, "%08lX%04X%02hX", |
| (unsigned long int) time (NULL), |
| - (unsigned int) getpid (), |
| + (unsigned int) getpid () % 65535, |
| cnt & 0xFF); |
| cnt++; |
| return buf; |
| |
| |
