diff options
| author | Michal Srb <msrb@suse.com> | 2017-07-20 17:05:23 +0200 |
|---|---|---|
| committer | Julien Cristau <jcristau@debian.org> | 2017-10-04 20:47:13 +0200 |
| commit | 672bb944311392e2415b39c0d63b1e1902905bcd (patch) | |
| tree | 903655fe98d7b47bcf25e860dc9606393bb4fb19 | |
| parent | d1e670a4a8704b8708e493ab6155589bcd570608 (diff) | |
pcfGetProperties: Check string boundaries (CVE-2017-13722)
Without the checks a malformed PCF file can cause the library to make
atom from random heap memory that was behind the `strings` buffer.
This may crash the process or leak information.
Signed-off-by: Julien Cristau <jcristau@debian.org>
| -rw-r--r-- | src/bitmap/pcfread.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/src/bitmap/pcfread.c b/src/bitmap/pcfread.c index dab1c44..ae34c28 100644 --- a/src/bitmap/pcfread.c +++ b/src/bitmap/pcfread.c @@ -45,6 +45,7 @@ from The Open Group. #include <stdarg.h> #include <stdint.h> +#include <string.h> void pcfError(const char* message, ...) @@ -311,11 +312,19 @@ pcfGetProperties(FontInfoPtr pFontInfo, FontFilePtr file, if (IS_EOF(file)) goto Bail; position += string_size; for (i = 0; i < nprops; i++) { + if (props[i].name >= string_size) { + pcfError("pcfGetProperties(): String starts out of bounds (%ld/%d)\n", props[i].name, string_size); + goto Bail; + } props[i].name = MakeAtom(strings + props[i].name, - strlen(strings + props[i].name), TRUE); + strnlen(strings + props[i].name, string_size - props[i].name), TRUE); if (isStringProp[i]) { + if (props[i].value >= string_size) { + pcfError("pcfGetProperties(): String starts out of bounds (%ld/%d)\n", props[i].value, string_size); + goto Bail; + } props[i].value = MakeAtom(strings + props[i].value, - strlen(strings + props[i].value), TRUE); + strnlen(strings + props[i].value, string_size - props[i].value), TRUE); } } free(strings); |