Fix buffer overflow vulnerability in curve, font, particles code.

Solves these security issues from T52924:
CVE-2017-12102
CVE-2017-12103
CVE-2017-12104

While the specific overflow issue may be fixed, loading the repro .blend
files may still crash because they are incomplete and corrupt. The way
they crash may be impossible to exploit, but this is difficult to prove.

Differential Revision: https://developer.blender.org/D3002

1 files changed, 6 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/font.c b/source/blender/blenkernel/intern/font.c
index 0f309fcfa77..bad73bc8910 100644
--- a/source/blender/blenkernel/intern/font.c
+++ b/source/blender/blenkernel/intern/font.c
@@ -677,6 +677,9 @@ bool BKE_vfont_to_curve_ex(Main *bmain, Object *ob, int mode, ListBase *r_nubase
 
 		/* Create unicode string */
 		mem_tmp = MEM_malloc_arrayN((slen + 1), sizeof(wchar_t), "convertedmem");
+		if (!mem_tmp) {
+			return ok;
+		}
 
 		BLI_strncpy_wchar_from_utf8(mem_tmp, cu->str, slen + 1);
 
@@ -684,6 +687,9 @@ bool BKE_vfont_to_curve_ex(Main *bmain, Object *ob, int mode, ListBase *r_nubase
 			cu->strinfo = MEM_calloc_arrayN((slen + 4), sizeof(CharInfo), "strinfo compat");
 		}
 		custrinfo = cu->strinfo;
+		if (!custrinfo) {
+			return ok;
+		}
 
 		mem = mem_tmp;
 	}