summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorSiddhesh Poyarekar <siddhesh@sourceware.org>2017-03-07 20:52:04 +0530
committerAdhemerval Zanella <adhemerval.zanella@linaro.org>2017-07-13 11:36:20 -0300
commitceeb0740ed04c48170f9f6f15fef55637ad84e1b (patch)
tree2adf4d58544aa760f7fe33a82dd1c3c6c32a0db8
parent24adabbe17d24b9cf4f42d81f546359f72515ce3 (diff)
downloadglibc-linaro/2.23/master.tar.gz
Ignore and remove LD_HWCAP_MASK for AT_SECURE programs (bug #21209)linaro/2.23/master
The LD_HWCAP_MASK environment variable may alter the selection of function variants for some architectures. For AT_SECURE process it means that if an outdated routine has a bug that would otherwise not affect newer platforms by default, LD_HWCAP_MASK will allow that bug to be exploited. To be on the safe side, ignore and disable LD_HWCAP_MASK for setuid binaries. [BZ #21209] * elf/rtld.c (process_envvars): Ignore LD_HWCAP_MASK for AT_SECURE processes. * sysdeps/generic/unsecvars.h: Add LD_HWCAP_MASK. (cherry picked from commit 1c1243b6fc33c029488add276e56570a07803bfd)
-rw-r--r--ChangeLog7
-rw-r--r--NEWS1
-rw-r--r--elf/rtld.c3
-rw-r--r--sysdeps/generic/unsecvars.h1
4 files changed, 11 insertions, 1 deletions
diff --git a/ChangeLog b/ChangeLog
index ce6fa9a83e..c23d1ecdc9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2017-03-07 Siddhesh Poyarekar <siddhesh@sourceware.org>
+
+ [BZ #21209]
+ * elf/rtld.c (process_envvars): Ignore LD_HWCAP_MASK for
+ AT_SECURE processes.
+ * sysdeps/generic/unsecvars.h: Add LD_HWCAP_MASK.
+
2017-06-19 Florian Weimer <fweimer@redhat.com>
* elf/rtld.c (audit_list_string): New variable.
diff --git a/NEWS b/NEWS
index 76a7f6a193..017d3c14f6 100644
--- a/NEWS
+++ b/NEWS
@@ -42,6 +42,7 @@ The following bugs are resolved with this release:
(CVE-2016-3075)
[20177] $dp is not initialized correctly in sysdeps/hppa/start.S
[20357] Incorrect cos result for 1.5174239687223976
+ [21209] Ignore and remove LD_HWCAP_MASK for AT_SECURE programs
[21289] Fix symbol redirect for fts_set
[21624] Unsafe alloca allows local attackers to alias stack and heap (CVE-2017-1000366)
diff --git a/elf/rtld.c b/elf/rtld.c
index 302bb63620..8f56d6edd3 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -2553,7 +2553,8 @@ process_envvars (enum mode *modep)
case 10:
/* Mask for the important hardware capabilities. */
- if (memcmp (envline, "HWCAP_MASK", 10) == 0)
+ if (!__libc_enable_secure
+ && memcmp (envline, "HWCAP_MASK", 10) == 0)
GLRO(dl_hwcap_mask) = __strtoul_internal (&envline[11], NULL,
0, 0);
break;
diff --git a/sysdeps/generic/unsecvars.h b/sysdeps/generic/unsecvars.h
index 3e56538b51..ac57bd5db0 100644
--- a/sysdeps/generic/unsecvars.h
+++ b/sysdeps/generic/unsecvars.h
@@ -10,6 +10,7 @@
"LD_DEBUG\0" \
"LD_DEBUG_OUTPUT\0" \
"LD_DYNAMIC_WEAK\0" \
+ "LD_HWCAP_MASK\0" \
"LD_LIBRARY_PATH\0" \
"LD_ORIGIN_PATH\0" \
"LD_PRELOAD\0" \