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-rw-r--r--patches/source/glibc/glibc.46703a39.diff119
1 files changed, 119 insertions, 0 deletions
diff --git a/patches/source/glibc/glibc.46703a39.diff b/patches/source/glibc/glibc.46703a39.diff
new file mode 100644
index 00000000..c21200be
--- /dev/null
+++ b/patches/source/glibc/glibc.46703a39.diff
@@ -0,0 +1,119 @@
+From 46703a3995aa3ca2b816814aa4ad05ed524194dd Mon Sep 17 00:00:00 2001
+From: Florian Weimer <fweimer@redhat.com>
+Date: Mon, 19 Jun 2017 22:31:04 +0200
+Subject: [PATCH] ld.so: Reject overly long LD_PRELOAD path elements
+
+(cherry picked from commit 6d0ba622891bed9d8394eef1935add53003b12e8)
+
+diff --git a/elf/rtld.c b/elf/rtld.c
+index 2fc33a6..4badcf6 100644
+--- a/elf/rtld.c
++++ b/elf/rtld.c
+@@ -99,6 +99,35 @@ uintptr_t __pointer_chk_guard_local
+ strong_alias (__pointer_chk_guard_local, __pointer_chk_guard)
+ #endif
+
++/* Length limits for names and paths, to protect the dynamic linker,
++ particularly when __libc_enable_secure is active. */
++#ifdef NAME_MAX
++# define SECURE_NAME_LIMIT NAME_MAX
++#else
++# define SECURE_NAME_LIMIT 255
++#endif
++#ifdef PATH_MAX
++# define SECURE_PATH_LIMIT PATH_MAX
++#else
++# define SECURE_PATH_LIMIT 1024
++#endif
++
++/* Check that AT_SECURE=0, or that the passed name does not contain
++ directories and is not overly long. Reject empty names
++ unconditionally. */
++static bool
++dso_name_valid_for_suid (const char *p)
++{
++ if (__glibc_unlikely (__libc_enable_secure))
++ {
++ /* Ignore pathnames with directories for AT_SECURE=1
++ programs, and also skip overlong names. */
++ size_t len = strlen (p);
++ if (len >= SECURE_NAME_LIMIT || memchr (p, '/', len) != NULL)
++ return false;
++ }
++ return *p != '\0';
++}
+
+ /* List of auditing DSOs. */
+ static struct audit_list
+@@ -716,6 +745,42 @@ static const char *preloadlist attribute_relro;
+ /* Nonzero if information about versions has to be printed. */
+ static int version_info attribute_relro;
+
++/* The LD_PRELOAD environment variable gives list of libraries
++ separated by white space or colons that are loaded before the
++ executable's dependencies and prepended to the global scope list.
++ (If the binary is running setuid all elements containing a '/' are
++ ignored since it is insecure.) Return the number of preloads
++ performed. */
++unsigned int
++handle_ld_preload (const char *preloadlist, struct link_map *main_map)
++{
++ unsigned int npreloads = 0;
++ const char *p = preloadlist;
++ char fname[SECURE_PATH_LIMIT];
++
++ while (*p != '\0')
++ {
++ /* Split preload list at space/colon. */
++ size_t len = strcspn (p, " :");
++ if (len > 0 && len < sizeof (fname))
++ {
++ memcpy (fname, p, len);
++ fname[len] = '\0';
++ }
++ else
++ fname[0] = '\0';
++
++ /* Skip over the substring and the following delimiter. */
++ p += len;
++ if (*p != '\0')
++ ++p;
++
++ if (dso_name_valid_for_suid (fname))
++ npreloads += do_preload (fname, main_map, "LD_PRELOAD");
++ }
++ return npreloads;
++}
++
+ static void
+ dl_main (const ElfW(Phdr) *phdr,
+ ElfW(Word) phnum,
+@@ -1462,23 +1527,8 @@ ERROR: ld.so: object '%s' cannot be loaded as audit interface: %s; ignored.\n",
+
+ if (__glibc_unlikely (preloadlist != NULL))
+ {
+- /* The LD_PRELOAD environment variable gives list of libraries
+- separated by white space or colons that are loaded before the
+- executable's dependencies and prepended to the global scope
+- list. If the binary is running setuid all elements
+- containing a '/' are ignored since it is insecure. */
+- char *list = strdupa (preloadlist);
+- char *p;
+-
+ HP_TIMING_NOW (start);
+-
+- /* Prevent optimizing strsep. Speed is not important here. */
+- while ((p = (strsep) (&list, " :")) != NULL)
+- if (p[0] != '\0'
+- && (__builtin_expect (! __libc_enable_secure, 1)
+- || strchr (p, '/') == NULL))
+- npreloads += do_preload (p, main_map, "LD_PRELOAD");
+-
++ npreloads += handle_ld_preload (preloadlist, main_map);
+ HP_TIMING_NOW (stop);
+ HP_TIMING_DIFF (diff, start, stop);
+ HP_TIMING_ACCUM_NT (load_time, diff);
+--
+2.9.3
+
+