mirror of
git://projects.qi-hardware.com/openwrt-xburst.git
synced 2024-11-23 20:30:37 +02:00
uClibc: fix free-after-use bug in __dns_lookup (closes #6886)
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@20384 3c298f89-4303-0410-b956-a3cf2f4a3e73
This commit is contained in:
juhosg
parent
198af96941
commit
fadc950fd9
@ -0,0 +1,45 @@
|
||||
From c602079e5b7ba998d1dd6cae4a305af80e6cba52 Mon Sep 17 00:00:00 2001
|
||||
From: Gabor Juhos <juhosg@openwrt.org>
|
||||
Date: Tue, 23 Mar 2010 08:35:27 +0100
|
||||
Subject: [PATCH] Fix use-after-free bug in __dns_lookup.
|
||||
|
||||
If the type of the first answer does not match with the requested type,
|
||||
then the dotted name will be freed. If there are no further answers in
|
||||
the DNS reply, this pointer will be used later on in the same function.
|
||||
Additionally it is passed to the caller, and may cause strange behaviour.
|
||||
|
||||
For example, the following busybox commands are triggering a segmentation
|
||||
fault with uClibc 0.9.30.x
|
||||
|
||||
- nslookup ipv6.google.com
|
||||
- ping ipv6.google.com
|
||||
- wget http//ipv6.google.com/
|
||||
|
||||
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
|
||||
|
||||
---
|
||||
|
||||
See https://dev.openwrt.org/ticket/6886 for a testcase
|
||||
---
|
||||
libc/inet/resolv.c | 4 +---
|
||||
1 files changed, 1 insertions(+), 3 deletions(-)
|
||||
|
||||
diff --git a/libc/inet/resolv.c b/libc/inet/resolv.c
|
||||
index 0a6fd7a..e76f0aa 100644
|
||||
--- a/libc/inet/resolv.c
|
||||
+++ b/libc/inet/resolv.c
|
||||
@@ -1501,10 +1501,8 @@ int attribute_hidden __dns_lookup(const char *name,
|
||||
memcpy(a, &ma, sizeof(ma));
|
||||
if (a->atype != T_SIG && (NULL == a->buf || (type != T_A && type != T_AAAA)))
|
||||
break;
|
||||
- if (a->atype != type) {
|
||||
- free(a->dotted);
|
||||
+ if (a->atype != type)
|
||||
continue;
|
||||
- }
|
||||
a->add_count = h.ancount - j - 1;
|
||||
if ((a->rdlength + sizeof(struct in_addr*)) * a->add_count > a->buflen)
|
||||
break;
|
||||
--
|
||||
1.5.3.2
|
||||
|
||||
@ -0,0 +1,45 @@
|
||||
From c602079e5b7ba998d1dd6cae4a305af80e6cba52 Mon Sep 17 00:00:00 2001
|
||||
From: Gabor Juhos <juhosg@openwrt.org>
|
||||
Date: Tue, 23 Mar 2010 08:35:27 +0100
|
||||
Subject: [PATCH] Fix use-after-free bug in __dns_lookup.
|
||||
|
||||
If the type of the first answer does not match with the requested type,
|
||||
then the dotted name will be freed. If there are no further answers in
|
||||
the DNS reply, this pointer will be used later on in the same function.
|
||||
Additionally it is passed to the caller, and may cause strange behaviour.
|
||||
|
||||
For example, the following busybox commands are triggering a segmentation
|
||||
fault with uClibc 0.9.30.x
|
||||
|
||||
- nslookup ipv6.google.com
|
||||
- ping ipv6.google.com
|
||||
- wget http//ipv6.google.com/
|
||||
|
||||
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
|
||||
|
||||
---
|
||||
|
||||
See https://dev.openwrt.org/ticket/6886 for a testcase
|
||||
---
|
||||
libc/inet/resolv.c | 4 +---
|
||||
1 files changed, 1 insertions(+), 3 deletions(-)
|
||||
|
||||
diff --git a/libc/inet/resolv.c b/libc/inet/resolv.c
|
||||
index 0a6fd7a..e76f0aa 100644
|
||||
--- a/libc/inet/resolv.c
|
||||
+++ b/libc/inet/resolv.c
|
||||
@@ -1501,10 +1501,8 @@ int attribute_hidden __dns_lookup(const char *name,
|
||||
memcpy(a, &ma, sizeof(ma));
|
||||
if (a->atype != T_SIG && (NULL == a->buf || (type != T_A && type != T_AAAA)))
|
||||
break;
|
||||
- if (a->atype != type) {
|
||||
- free(a->dotted);
|
||||
+ if (a->atype != type)
|
||||
continue;
|
||||
- }
|
||||
a->add_count = h.ancount - j - 1;
|
||||
if ((a->rdlength + sizeof(struct in_addr*)) * a->add_count > a->buflen)
|
||||
break;
|
||||
--
|
||||
1.5.3.2
|
||||
|
||||
@ -0,0 +1,45 @@
|
||||
From c602079e5b7ba998d1dd6cae4a305af80e6cba52 Mon Sep 17 00:00:00 2001
|
||||
From: Gabor Juhos <juhosg@openwrt.org>
|
||||
Date: Tue, 23 Mar 2010 08:35:27 +0100
|
||||
Subject: [PATCH] Fix use-after-free bug in __dns_lookup.
|
||||
|
||||
If the type of the first answer does not match with the requested type,
|
||||
then the dotted name will be freed. If there are no further answers in
|
||||
the DNS reply, this pointer will be used later on in the same function.
|
||||
Additionally it is passed to the caller, and may cause strange behaviour.
|
||||
|
||||
For example, the following busybox commands are triggering a segmentation
|
||||
fault with uClibc 0.9.30.x
|
||||
|
||||
- nslookup ipv6.google.com
|
||||
- ping ipv6.google.com
|
||||
- wget http//ipv6.google.com/
|
||||
|
||||
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
|
||||
|
||||
---
|
||||
|
||||
See https://dev.openwrt.org/ticket/6886 for a testcase
|
||||
---
|
||||
libc/inet/resolv.c | 4 +---
|
||||
1 files changed, 1 insertions(+), 3 deletions(-)
|
||||
|
||||
diff --git a/libc/inet/resolv.c b/libc/inet/resolv.c
|
||||
index 0a6fd7a..e76f0aa 100644
|
||||
--- a/libc/inet/resolv.c
|
||||
+++ b/libc/inet/resolv.c
|
||||
@@ -1501,10 +1501,8 @@ int attribute_hidden __dns_lookup(const char *name,
|
||||
memcpy(a, &ma, sizeof(ma));
|
||||
if (a->atype != T_SIG && (NULL == a->buf || (type != T_A && type != T_AAAA)))
|
||||
break;
|
||||
- if (a->atype != type) {
|
||||
- free(a->dotted);
|
||||
+ if (a->atype != type)
|
||||
continue;
|
||||
- }
|
||||
a->add_count = h.ancount - j - 1;
|
||||
if ((a->rdlength + sizeof(struct in_addr*)) * a->add_count > a->buflen)
|
||||
break;
|
||||
--
|
||||
1.5.3.2
|
||||
|
||||
Loading…
Reference in New Issue
Block a user