Fix for CVE-2014-1943
Modified version of this patch:
which is for php 5.4 code.
php 5.4 code is here:
Got this verson from johannes.schlueter@oracle.com who is a
PHP community member.
Comparing the 2 versions and this one looks believable.
diff -Naurp php-5.3.28/ext/fileinfo/libmagic/ascmagic.c php-5.3.28.oden/ext/fileinfo/libmagic/ascmagic.c
--- php-5.3.28/ext/fileinfo/libmagic/ascmagic.c 2013-12-10 19:04:57.000000000 +0000
+++ php-5.3.28.oden/ext/fileinfo/libmagic/ascmagic.c 2014-02-19 15:59:40.000000000 +0000
@@ -145,7 +145,7 @@ file_ascmagic_with_encoding(struct magic
== NULL)
goto done;
if ((rv = file_softmagic(ms, utf8_buf,
- (size_t)(utf8_end - utf8_buf), TEXTTEST, text)) == 0)
+ (size_t)(utf8_end - utf8_buf), 0, TEXTTEST, text)) == 0)
rv = -1;
}
--- php-5.3.28/ext/fileinfo/libmagic/file.h 2013-12-10 19:04:57.000000000 +0000
+++ php-5.3.28.oden/ext/fileinfo/libmagic/file.h 2014-02-19 15:59:40.000000000 +0000
@@ -414,7 +414,7 @@ protected int file_encoding(struct magic
unichar **, size_t *, const char **, const char **, const char **);
protected int file_is_tar(struct magic_set *, const unsigned char *, size_t);
protected int file_softmagic(struct magic_set *, const unsigned char *, size_t,
- int, int);
+ size_t, int, int);
protected struct mlist *file_apprentice(struct magic_set *, const char *, int);
protected uint64_t file_signextend(struct magic_set *, struct magic *,
uint64_t);
--- php-5.3.28/ext/fileinfo/libmagic/funcs.c 2013-12-10 19:04:57.000000000 +0000
+++ php-5.3.28.oden/ext/fileinfo/libmagic/funcs.c 2014-02-19 15:59:40.000000000 +0000
@@ -235,7 +235,7 @@ file_buffer(struct magic_set *ms, php_st
/* try soft magic tests */
if ((ms->flags & MAGIC_NO_CHECK_SOFT) == 0)
- if ((m = file_softmagic(ms, ubuf, nb, BINTEST,
+ if ((m = file_softmagic(ms, ubuf, nb, 0, BINTEST,
looks_text)) != 0) {
if ((ms->flags & MAGIC_DEBUG) != 0)
(void)fprintf(stderr, "softmagic %d\n", m);
diff -Naurp php-5.3.28/ext/fileinfo/libmagic/softmagic.c php-5.3.28.oden/ext/fileinfo/libmagic/softmagic.c
--- php-5.3.28/ext/fileinfo/libmagic/softmagic.c 2013-12-10 19:04:57.000000000 +0000
+++ php-5.3.28.oden/ext/fileinfo/libmagic/softmagic.c 2014-02-19 15:59:40.000000000 +0000
@@ -48,9 +48,9 @@ FILE_RCSID("@(#)$File: softmagic.c,v 1.1
private int match(struct magic_set *, struct magic *, uint32_t,
- const unsigned char *, size_t, int, int);
+ const unsigned char *, size_t, int, int, int);
private int mget(struct magic_set *, const unsigned char *,
- struct magic *, size_t, unsigned int, int);
+ struct magic *, size_t, unsigned int, int, int);
private int magiccheck(struct magic_set *, struct magic *);
private int32_t mprint(struct magic_set *, struct magic *);
private int32_t moffset(struct magic_set *, struct magic *);
@@ -72,13 +72,13 @@ private void cvt_64(union VALUETYPE *, c
/*ARGSUSED1*/ /* nbytes passed for regularity, maybe need later */
protected int
file_softmagic(struct magic_set *ms, const unsigned char *buf, size_t nbytes,
- int mode, int text)
+ size_t level, int mode, int text)
{
struct mlist *ml;
int rv;
for (ml = ms->mlist->next; ml != ms->mlist; ml = ml->next)
if ((rv = match(ms, ml->magic, ml->nmagic, buf, nbytes, mode,
- text)) != 0)
+ text, level)) != 0)
return rv;
return 0;
@@ -113,7 +113,8 @@ file_softmagic(struct magic_set *ms, con
*/
private int
match(struct magic_set *ms, struct magic *magic, uint32_t nmagic,
- const unsigned char *s, size_t nbytes, int mode, int text)
+ const unsigned char *s, size_t nbytes, int mode, int text,
+ int recursion_level)
{
uint32_t magindex = 0;
unsigned int cont_level = 0;
@@ -145,7 +146,7 @@ match(struct magic_set *ms, struct magic
ms->line = m->lineno;
/* if main entry matches, print it... */
- switch (mget(ms, s, m, nbytes, cont_level, text)) {
+ switch (mget(ms, s, m, nbytes, cont_level, text, recursion_level + 1)) {
case -1:
return -1;
case 0:
@@ -227,7 +228,7 @@ match(struct magic_set *ms, struct magic
continue;
}
#endif
- switch (mget(ms, s, m, nbytes, cont_level, text)) {
+ switch (mget(ms, s, m, nbytes, cont_level, text, recursion_level + 1)) {
case -1:
return -1;
case 0:
@@ -997,12 +998,18 @@ mcopy(struct magic_set *ms, union VALUET
private int
mget(struct magic_set *ms, const unsigned char *s,
- struct magic *m, size_t nbytes, unsigned int cont_level, int text)
+ struct magic *m, size_t nbytes, unsigned int cont_level, int text,
+ int recursion_level)
{
uint32_t offset = ms->offset;
uint32_t count = m->str_range;
union VALUETYPE *p = &ms->ms_value;
+ if (recursion_level >= 20) {
+ file_error(ms, 0, "recursion nesting exceeded");
+ return -1;
+ }
+
if (mcopy(ms, p, m->type, m->flag & INDIR, s, offset, nbytes, count) == -1)
return -1;
@@ -1550,13 +1557,15 @@ mget(struct magic_set *ms, const unsigne
break;
case FILE_INDIRECT:
+ if (offset == 0)
+ return 0;
if ((ms->flags & (MAGIC_MIME|MAGIC_APPLE)) == 0 &&
file_printf(ms, "%s", m->desc) == -1)
return -1;
if (nbytes < offset)
return 0;
return file_softmagic(ms, s + offset, nbytes - offset,
- BINTEST, text);
+ recursion_level, BINTEST, text);
case FILE_DEFAULT: /* nothing to check */
default:
diff -Naurp php-5.3.28/ext/fileinfo/tests/cve-2014-1943.phpt php-5.3.28.oden/ext/fileinfo/tests/cve-2014-1943.phpt
--- php-5.3.28/ext/fileinfo/tests/cve-2014-1943.phpt 1970-01-01 00:00:00.000000000 +0000
+++ php-5.3.28.oden/ext/fileinfo/tests/cve-2014-1943.phpt 2014-02-19 16:00:20.000000000 +0000
@@ -0,0 +1,39 @@
+--TEST--
+Bug #66731: file: infinite recursion
+--SKIPIF--
+<?php
+if (!class_exists('finfo'))
+ die('skip no fileinfo extension');
+--FILE--
+<?php
+$fd = __DIR__.'/cve-2014-1943.data';
+$fm = __DIR__.'/cve-2014-1943.magic';
+
+$a = "\105\122\000\000\000\000\000";
+$b = str_repeat("\001", 250000);
+$m = "0 byte x\n".
+ ">(1.b) indirect x\n";
+
+file_put_contents($fd, $a);
+$fi = finfo_open(FILEINFO_NONE);
+var_dump(finfo_file($fi, $fd));
+finfo_close($fi);
+
+file_put_contents($fd, $b);
+file_put_contents($fm, $m);
+$fi = finfo_open(FILEINFO_NONE, $fm);
+var_dump(finfo_file($fi, $fd));
+finfo_close($fi);
+?>
+Done
+--CLEAN--
+<?php
+@unlink(__DIR__.'/cve-2014-1943.data');
+@unlink(__DIR__.'/cve-2014-1943.magic');
+?>
+--EXPECTF--
+string(%d) "%s"
+
+Warning: finfo_file(): Failed identify data 0:(null) in %s on line %d
+bool(false)
+Done