procps-ng/library-avoid-problems-involving-supgid-mishandling.patch
2019-12-25 17:13:31 +08:00

73 lines
2.5 KiB
Diff

From f9a8009e27d47a61096ff7bf1de37a90f0f801e6 Mon Sep 17 00:00:00 2001
From: Jim Warner <james.warner@comcast.net>
Date: Wed, 30 May 2018 00:00:00 -0500
Subject: [PATCH 08/65] library: avoid problems involving 'supgid' mishandling
Following that patch referenced below, the top SUPGRPS
field would produce a segmentation fault and ps SUPGRP
would often show "(null)". Such problems resulted from
some faulty logic in the status2proc() routine dealing
with 'Groups' (supgid) which served as a source field.
For many processes the original code produced an empty
string which prevented conversion to the expected "-".
Moreover, prior to release 3.3.15 such an empty string
will become 0 after strtol() which pwcache_get_group()
translates to 'root' yielding very misleading results.
So, now we'll check for empty '/proc/#/status/Groups:'
fields & consistently provide a "-" value for callers.
[ we'll also protect against future problems in that ]
[ new qualys logic by always ensuring valid 'supgrp' ]
[ pointers - logic which revealed our original flaw! ]
Reference(s):
. original qualys patch
0071-proc-readproc.c-Harden-supgrps_from_supgids.patch
Signed-off-by: Jim Warner <james.warner@comcast.net>
---
proc/readproc.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/proc/readproc.c b/proc/readproc.c
index 0f00231..ea7a31b 100644
--- a/proc/readproc.c
+++ b/proc/readproc.c
@@ -387,12 +387,15 @@ ENTER(0x220);
P->vm_swap = strtol(S,&S,10);
continue;
case_Groups:
- { char *nl = strchr(S, '\n');
- size_t j = nl ? (size_t)(nl - S) : strlen(S);
+ { char *ss = S, *nl = strchr(S, '\n');
+ size_t j;
+ while (' ' == *ss || '\t' == *ss) ss++;
+ if (ss >= nl) continue;
+ j = nl ? (size_t)(nl - ss) : strlen(ss);
if (j > 0 && j < INT_MAX) {
P->supgid = xmalloc(j+1); // +1 in case space disappears
- memcpy(P->supgid, S, j);
+ memcpy(P->supgid, ss, j);
if (unlikely(' ' != P->supgid[--j])) ++j;
P->supgid[j] = '\0'; // whack the space or the newline
for ( ; j; j--)
@@ -472,7 +475,11 @@ static void supgrps_from_supgids (proc_t *p) {
while (',' == *s) ++s;
gid = strtol(s, &end, 10);
- if (end <= s) break;
+ if (end <= s) {
+ if (!p->supgrp)
+ p->supgrp = xstrdup("-");
+ break;
+ }
s = end;
g = pwcache_get_group(gid);
--
2.6.4.windows.1