diff options
| author | DJ Delorie <dj@redhat.com> | 2021-02-25 16:08:21 -0500 |
|---|---|---|
| committer | Dmitry V. Levin <ldv@altlinux.org> | 2021-03-08 10:12:28 +0000 |
| commit | c49cbcdc321dd31026955f7f170d0018848b3d2f (patch) | |
| tree | 22b452cf796064003357c95f2371aad3000ab0ff | |
| parent | 2777e19c0550ca6c21f3604fad02084a8130f3a5 (diff) | |
nscd: Fix double free in netgroupcache [BZ #27462]
In commit 745664bd798ec8fd50438605948eea594179fba1 a use-after-free
was fixed, but this led to an occasional double-free. This patch
tracks the "live" allocation better.
Tested manually by a third party.
Related: RHBZ 1927877
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
(cherry picked from commit dca565886b5e8bd7966e15f0ca42ee5cff686673)
| -rw-r--r-- | NEWS | 6 | ||||
| -rw-r--r-- | nscd/netgroupcache.c | 4 |
2 files changed, 8 insertions, 2 deletions
@@ -99,6 +99,11 @@ Security related changes: CVE-2020-29562: An assertion failure has been fixed in the iconv function when invoked with UCS4 input containing an invalid character. + CVE-2021-27645: The nameserver caching daemon (nscd), when processing + a request for netgroup lookup, may crash due to a double-free, + potentially resulting in degraded service or Denial of Service on the + local system. Reported by Chris Schanzle. + The following bugs are resolved with this release: [6889] 'PWD' mentioned but not specified @@ -195,6 +200,7 @@ The following bugs are resolved with this release: character sets (CVE-2020-27618) [26383] bind_textdomain_codeset doesn't accept //TRANSLIT anymore [26923] Assertion failure in iconv when converting invalid UCS4 (CVE-2020-29562) + [27462] nscd: double-free in nscd (CVE-2021-27645) Version 2.27 diff --git a/nscd/netgroupcache.c b/nscd/netgroupcache.c index 3adc5387d6..e75cbc0573 100644 --- a/nscd/netgroupcache.c +++ b/nscd/netgroupcache.c @@ -248,7 +248,7 @@ addgetnetgrentX (struct database_dyn *db, int fd, request_header *req, : NULL); ndomain = (ndomain ? newbuf + ndomaindiff : NULL); - buffer = newbuf; + *tofreep = buffer = newbuf; } nhost = memcpy (buffer + bufused, @@ -319,7 +319,7 @@ addgetnetgrentX (struct database_dyn *db, int fd, request_header *req, else if (status == NSS_STATUS_TRYAGAIN && e == ERANGE) { buflen *= 2; - buffer = xrealloc (buffer, buflen); + *tofreep = buffer = xrealloc (buffer, buflen); } else if (status == NSS_STATUS_RETURN || status == NSS_STATUS_NOTFOUND |