[OE-core] [PATCH 01/21] glibc: CVE-2015-8777
Armin Kuster
akuster808 at gmail.com
Sat Feb 6 23:14:42 UTC 2016
From: Armin Kuster <akuster at mvista.com>
The process_envvars function in elf/rtld.c in the GNU C Library (aka glibc or
libc6) before 2.23 allows local users to bypass a pointer-guarding protection
mechanism via a zero value of the LD_POINTER_GUARD environment variable.
(From OE-Core rev: 22570ba08d7c6157aec58764c73b1134405b0252)
Signed-off-by: Armin Kuster <akuster at mvista.com>
Signed-off-by: Robert Yang <liezhi.yang at windriver.com>
Signed-off-by: Richard Purdie <richard.purdie at linuxfoundation.org>
Signed-off-by: Armin Kuster <akuster at mvista.com>
---
meta/recipes-core/glibc/glibc/CVE-2015-8777.patch | 122 ++++++++++++++++++++++
meta/recipes-core/glibc/glibc_2.21.bb | 1 +
2 files changed, 123 insertions(+)
create mode 100644 meta/recipes-core/glibc/glibc/CVE-2015-8777.patch
diff --git a/meta/recipes-core/glibc/glibc/CVE-2015-8777.patch b/meta/recipes-core/glibc/glibc/CVE-2015-8777.patch
new file mode 100644
index 0000000..9b9ab3b
--- /dev/null
+++ b/meta/recipes-core/glibc/glibc/CVE-2015-8777.patch
@@ -0,0 +1,122 @@
+From a014cecd82b71b70a6a843e250e06b541ad524f7 Mon Sep 17 00:00:00 2001
+From: Florian Weimer <fweimer at redhat.com>
+Date: Thu, 15 Oct 2015 09:23:07 +0200
+Subject: [PATCH] Always enable pointer guard [BZ #18928]
+
+Honoring the LD_POINTER_GUARD environment variable in AT_SECURE mode
+has security implications. This commit enables pointer guard
+unconditionally, and the environment variable is now ignored.
+
+ [BZ #18928]
+ * sysdeps/generic/ldsodefs.h (struct rtld_global_ro): Remove
+ _dl_pointer_guard member.
+ * elf/rtld.c (_rtld_global_ro): Remove _dl_pointer_guard
+ initializer.
+ (security_init): Always set up pointer guard.
+ (process_envvars): Do not process LD_POINTER_GUARD.
+
+Upstream-Status: Backport
+CVE: CVE-2015-8777
+[Yocto # 8980]
+
+https://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commit;h=a014cecd82b71b70a6a843e250e06b541ad524f7
+
+Signed-off-by: Armin Kuster <akuster at mvista.com>
+
+---
+ ChangeLog | 10 ++++++++++
+ NEWS | 13 ++++++++-----
+ elf/rtld.c | 15 ++++-----------
+ sysdeps/generic/ldsodefs.h | 3 ---
+ 4 files changed, 22 insertions(+), 19 deletions(-)
+
+Index: git/elf/rtld.c
+===================================================================
+--- git.orig/elf/rtld.c
++++ git/elf/rtld.c
+@@ -163,7 +163,6 @@ struct rtld_global_ro _rtld_global_ro at
+ ._dl_hwcap_mask = HWCAP_IMPORTANT,
+ ._dl_lazy = 1,
+ ._dl_fpu_control = _FPU_DEFAULT,
+- ._dl_pointer_guard = 1,
+ ._dl_pagesize = EXEC_PAGESIZE,
+ ._dl_inhibit_cache = 0,
+
+@@ -710,15 +709,12 @@ security_init (void)
+ #endif
+
+ /* Set up the pointer guard as well, if necessary. */
+- if (GLRO(dl_pointer_guard))
+- {
+- uintptr_t pointer_chk_guard = _dl_setup_pointer_guard (_dl_random,
+- stack_chk_guard);
++ uintptr_t pointer_chk_guard
++ = _dl_setup_pointer_guard (_dl_random, stack_chk_guard);
+ #ifdef THREAD_SET_POINTER_GUARD
+- THREAD_SET_POINTER_GUARD (pointer_chk_guard);
++ THREAD_SET_POINTER_GUARD (pointer_chk_guard);
+ #endif
+- __pointer_chk_guard_local = pointer_chk_guard;
+- }
++ __pointer_chk_guard_local = pointer_chk_guard;
+
+ /* We do not need the _dl_random value anymore. The less
+ information we leave behind, the better, so clear the
+@@ -2478,9 +2474,6 @@ process_envvars (enum mode *modep)
+ GLRO(dl_use_load_bias) = envline[14] == '1' ? -1 : 0;
+ break;
+ }
+-
+- if (memcmp (envline, "POINTER_GUARD", 13) == 0)
+- GLRO(dl_pointer_guard) = envline[14] != '0';
+ break;
+
+ case 14:
+Index: git/sysdeps/generic/ldsodefs.h
+===================================================================
+--- git.orig/sysdeps/generic/ldsodefs.h
++++ git/sysdeps/generic/ldsodefs.h
+@@ -590,9 +590,6 @@ struct rtld_global_ro
+ /* List of auditing interfaces. */
+ struct audit_ifaces *_dl_audit;
+ unsigned int _dl_naudit;
+-
+- /* 0 if internal pointer values should not be guarded, 1 if they should. */
+- EXTERN int _dl_pointer_guard;
+ };
+ # define __rtld_global_attribute__
+ # if IS_IN (rtld)
+Index: git/ChangeLog
+===================================================================
+--- git.orig/ChangeLog
++++ git/ChangeLog
+@@ -1,3 +1,13 @@
++2015-10-15 Florian Weimer <fweimer at redhat.com>
++
++ [BZ #18928]
++ * sysdeps/generic/ldsodefs.h (struct rtld_global_ro): Remove
++ _dl_pointer_guard member.
++ * elf/rtld.c (_rtld_global_ro): Remove _dl_pointer_guard
++ initializer.
++ (security_init): Always set up pointer guard.
++ (process_envvars): Do not process LD_POINTER_GUARD.
++
+ 2015-02-06 Carlos O'Donell <carlos at systemhalted.org>
+
+ * version.h (RELEASE): Set to "stable".
+Index: git/NEWS
+===================================================================
+--- git.orig/NEWS
++++ git/NEWS
+@@ -19,7 +19,10 @@ Version 2.21
+ 17722, 17723, 17724, 17725, 17732, 17733, 17744, 17745, 17746, 17747,
+ 17748, 17775, 17777, 17780, 17781, 17782, 17791, 17793, 17796, 17797,
+ 17801, 17803, 17806, 17834, 17844, 17848, 17868, 17869, 17870, 17885,
+- 17892.
++ 17892, 18928.
++
++* The LD_POINTER_GUARD environment variable can no longer be used to
++ disable the pointer guard feature. It is always enabled.
+
+ * CVE-2015-1472 Under certain conditions wscanf can allocate too little
+ memory for the to-be-scanned arguments and overflow the allocated
diff --git a/meta/recipes-core/glibc/glibc_2.21.bb b/meta/recipes-core/glibc/glibc_2.21.bb
index 3bba734..efbcc9c 100644
--- a/meta/recipes-core/glibc/glibc_2.21.bb
+++ b/meta/recipes-core/glibc/glibc_2.21.bb
@@ -48,6 +48,7 @@ EGLIBCPATCHES = "\
#
CVEPATCHES = "\
file://CVE-2015-1781-resolv-nss_dns-dns-host.c-buffer-overf.patch \
+ file://CVE-2015-8777.patch \
"
LIC_FILES_CHKSUM = "file://LICENSES;md5=e9a558e243b36d3209f380deb394b213 \
--
2.3.5
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