CaROS/poky
3
1
Fork 0
mirror of https://git.yoctoproject.org/git/poky synced 2026-01-01 13:58:04 +00:00
Code Issues Packages Projects Releases Wiki Activity

glibc: Fixes a heap buffer overflow in glibc wscanf.

Browse Source 
References:
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-1472
https://sourceware.org/ml/libc-alpha/2015-02/msg00119.html
http://openwall.com/lists/oss-security/2015/02/04/1

Reference to upstream fix:
https://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commit;
h=5bd80bfe9ca0d955bfbbc002781bc7b01b6bcb06

(From OE-Core rev: 5aa90eef9b503ba0ffb138e146add6f430dea917)

Signed-off-by: Sona Sarmadi <sona.sarmadi@enea.com>
Signed-off-by: Tudor Florea <tudor.florea@enea.com>

Hand applied.

Signed-off-by: Armin Kuster <akuster808@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
This commit is contained in:
Armin Kuster 2015-12-16 20:32:06 -08:00 committed by Richard Purdie
parent a779191033
commit faf6ada4f2
2 changed files with 109 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

108
meta/recipes-core/glibc/glibc/CVE-2015-1472-wscanf-allocates-too-little-memory.patch Normal file
View File

@ -0,0 +1,108 @@
CVE-2015-1472: wscanf allocates too little memory
BZ #16618
Under certain conditions wscanf can allocate too little memory for the
to-be-scanned arguments and overflow the allocated buffer. The
implementation now correctly computes the required buffer size when
using malloc.
A regression test was added to tst-sscanf.
Upstream-Status: Backport
The patch is from (Paul Pluzhnikov <ppluzhnikov@google.com>):
[https://sourceware.org/git/?p=glibc.git;a=patch;h=5bd80bfe9ca0d955bfbbc002781bc7b01b6bcb06]
diff -ruN a/ChangeLog b/ChangeLog
--- a/ChangeLog 2015-09-22 10:20:14.399408389 +0200
+++ b/ChangeLog 2015-09-22 10:33:07.374388595 +0200
@@ -1,3 +1,12 @@
+2015-02-05 Paul Pluzhnikov <ppluzhnikov@google.com>
+
+ [BZ #16618] CVE-2015-1472
+ * stdio-common/tst-sscanf.c (main): Test for buffer overflow.
+ * stdio-common/vfscanf.c (_IO_vfscanf_internal): Compute needed
+ size in bytes. Store needed elements in wpmax. Use needed size
+ in bytes for extend_alloca.
+
+
2014-12-16 Florian Weimer <fweimer@redhat.com>
[BZ #17630]
diff -ruN a/stdio-common/tst-sscanf.c b/stdio-common/tst-sscanf.c
--- a/stdio-common/tst-sscanf.c 2015-09-22 10:20:09.995596201 +0200
+++ b/stdio-common/tst-sscanf.c 2015-09-22 10:21:39.211791399 +0200
@@ -233,5 +233,38 @@
}
}
+ /* BZ #16618
+ The test will segfault during SSCANF if the buffer overflow
+ is not fixed. The size of `s` is such that it forces the use
+ of malloc internally and this triggers the incorrect computation.
+ Thus the value for SIZE is arbitrariy high enough that malloc
+ is used. */
+ {
+#define SIZE 131072
+ CHAR *s = malloc ((SIZE + 1) * sizeof (*s));
+ if (s == NULL)
+ abort ();
+ for (size_t i = 0; i < SIZE; i++)
+ s[i] = L('0');
+ s[SIZE] = L('\0');
+ int i = 42;
+ /* Scan multi-digit zero into `i`. */
+ if (SSCANF (s, L("%d"), &i) != 1)
+ {
+ printf ("FAIL: bug16618: SSCANF did not read one input item.\n");
+ result = 1;
+ }
+ if (i != 0)
+ {
+ printf ("FAIL: bug16618: Value of `i` was not zero as expected.\n");
+ result = 1;
+ }
+ free (s);
+ if (result != 1)
+ printf ("PASS: bug16618: Did not crash.\n");
+#undef SIZE
+ }
+
+
return result;
}
diff -ruN a/stdio-common/vfscanf.c b/stdio-common/vfscanf.c
--- a/stdio-common/vfscanf.c 2015-09-22 10:20:14.051423230 +0200
+++ b/stdio-common/vfscanf.c 2015-09-22 10:21:39.215791228 +0200
@@ -279,9 +279,10 @@
if (__glibc_unlikely (wpsize == wpmax)) \
{ \
CHAR_T *old = wp; \
- size_t newsize = (UCHAR_MAX + 1 > 2 * wpmax \
- ? UCHAR_MAX + 1 : 2 * wpmax); \
- if (use_malloc || !__libc_use_alloca (newsize)) \
+ bool fits = __glibc_likely (wpmax <= SIZE_MAX / sizeof (CHAR_T) / 2); \
+ size_t wpneed = MAX (UCHAR_MAX + 1, 2 * wpmax); \
+ size_t newsize = fits ? wpneed * sizeof (CHAR_T) : SIZE_MAX; \
+ if (!__libc_use_alloca (newsize)) \
{ \
wp = realloc (use_malloc ? wp : NULL, newsize); \
if (wp == NULL) \
@@ -293,14 +294,13 @@
} \
if (! use_malloc) \
MEMCPY (wp, old, wpsize); \
- wpmax = newsize; \
+ wpmax = wpneed; \
use_malloc = true; \
} \
else \
{ \
size_t s = wpmax * sizeof (CHAR_T); \
- wp = (CHAR_T *) extend_alloca (wp, s, \
- newsize * sizeof (CHAR_T)); \
+ wp = (CHAR_T *) extend_alloca (wp, s, newsize); \
wpmax = s / sizeof (CHAR_T); \
if (old != NULL) \
MEMCPY (wp, old, wpsize); \

1
meta/recipes-core/glibc/glibc_2.20.bb
View File

@ -46,6 +46,7 @@ CVEPATCHES = "\
file://CVE-2012-3406-Stack-overflow-in-vfprintf-BZ-16617.patch \
file://CVE-2014-9402_endless-loop-in-getaddr_r.patch \
file://CVE-2015-1781-resolv-nss_dns-dns-host.c-buffer-overf.patch \
file://CVE-2015-1472-wscanf-allocates-too-little-memory.patch \
"
LIC_FILES_CHKSUM = "file://LICENSES;md5=e9a558e243b36d3209f380deb394b213 \
file://COPYING;md5=b234ee4d69f5fce4486a80fdaf4a4263 \