Juergen Daubert
73e65ee004
Important security fix, a local attacker could exploit this to gain root privileges. See - http://seclists.org/fulldisclosure/2010/Oct/257 - http://seclists.org/fulldisclosure/2010/Oct/344
99 lines
3.2 KiB
Diff
99 lines
3.2 KiB
Diff
# http://seclists.org/fulldisclosure/2010/Oct/257
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# http://sourceware.org/ml/libc-hacker/2010-10/msg00007.html
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Path elements containing $ORIGIN should always be ignored in privileged
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programs.
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Andreas.
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2010-10-18 Andreas Schwab <schwab@redhat.com>
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* elf/dl-load.c (is_dst): Remove last parameter.
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(_dl_dst_count): Ignore $ORIGIN in privileged programs.
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(_dl_dst_substitute): Likewise.
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---
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elf/dl-load.c | 30 +++++++++++++-----------------
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1 files changed, 13 insertions(+), 17 deletions(-)
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diff --git a/elf/dl-load.c b/elf/dl-load.c
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index a7162eb..776f7e4 100644
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--- a/elf/dl-load.c
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+++ b/elf/dl-load.c
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@@ -169,8 +169,7 @@ local_strdup (const char *s)
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static size_t
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-is_dst (const char *start, const char *name, const char *str,
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- int is_path, int secure)
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+is_dst (const char *start, const char *name, const char *str, int is_path)
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{
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size_t len;
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bool is_curly = false;
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@@ -199,11 +198,6 @@ is_dst (const char *start, const char *name, const char *str,
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&& (!is_path || name[len] != ':'))
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return 0;
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- if (__builtin_expect (secure, 0)
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- && ((name[len] != '\0' && (!is_path || name[len] != ':'))
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- || (name != start + 1 && (!is_path || name[-2] != ':'))))
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- return 0;
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-
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return len;
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}
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@@ -218,13 +212,12 @@ _dl_dst_count (const char *name, int is_path)
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{
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size_t len;
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- /* $ORIGIN is not expanded for SUID/GUID programs (except if it
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- is $ORIGIN alone) and it must always appear first in path. */
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+ /* $ORIGIN is not expanded for SUID/GUID programs. */
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++name;
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- if ((len = is_dst (start, name, "ORIGIN", is_path,
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- INTUSE(__libc_enable_secure))) != 0
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- || (len = is_dst (start, name, "PLATFORM", is_path, 0)) != 0
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- || (len = is_dst (start, name, "LIB", is_path, 0)) != 0)
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+ if (((len = is_dst (start, name, "ORIGIN", is_path)) != 0
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+ && !INTUSE(__libc_enable_secure))
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+ || (len = is_dst (start, name, "PLATFORM", is_path)) != 0
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+ || (len = is_dst (start, name, "LIB", is_path)) != 0)
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++cnt;
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name = strchr (name + len, '$');
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@@ -256,9 +249,12 @@ _dl_dst_substitute (struct link_map *l, const char *name, char *result,
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size_t len;
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++name;
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- if ((len = is_dst (start, name, "ORIGIN", is_path,
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- INTUSE(__libc_enable_secure))) != 0)
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+ if ((len = is_dst (start, name, "ORIGIN", is_path)) != 0)
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{
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+ /* Ignore this path element in SUID/SGID programs. */
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+ if (INTUSE(__libc_enable_secure))
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+ repl = (const char *) -1;
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+ else
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#ifndef SHARED
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if (l == NULL)
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repl = _dl_get_origin ();
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@@ -266,9 +262,9 @@ _dl_dst_substitute (struct link_map *l, const char *name, char *result,
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#endif
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repl = l->l_origin;
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}
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- else if ((len = is_dst (start, name, "PLATFORM", is_path, 0)) != 0)
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+ else if ((len = is_dst (start, name, "PLATFORM", is_path)) != 0)
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repl = GLRO(dl_platform);
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- else if ((len = is_dst (start, name, "LIB", is_path, 0)) != 0)
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+ else if ((len = is_dst (start, name, "LIB", is_path)) != 0)
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repl = DL_DST_LIB;
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if (repl != NULL && repl != (const char *) -1)
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--
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1.7.2.3
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--
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Andreas Schwab, schwab@redhat.com
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GPG Key fingerprint = D4E8 DBE3 3813 BB5D FA84 5EC7 45C6 250E 6F00 984E
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"And now for something completely different."
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