[tlbuild] Test failures for dvipdmfx on OpenBSD
Masamichi Hosoda
trueroad at trueroad.jp
Thu Jan 7 11:24:31 CET 2021
Hi all,
>> dvipdfmx non-deterministic behaviour
>
> Devs from Japan investigated this;
>
> * It crashes at cmap_read.c L.579
> MATCH_OP(tok1, "begincodespacerange")
> * The crash occurs when the size of tok1->data is smaller
> than strlen("begincodespacerange").
> * When you use strncmp instead of memcmp in
> #define MATCH_OP(t,n)
> at cmap_read.c L.405, the crash will not happen.
> OTOH, it may match longer strings such as "begincodespacerangeeeee".
> * FYI, t1_load.c L.93 uses strncmp in a similar function MATCH_OP(t,n).
I would like to propose a patch
that can prevent the memory access violations
and does not allow long tokens like "begincodespacerangeeeee"
to match the string.
```
--- a/source/texk/dvipdfm-x/cmap_read.c
+++ b/source/texk/dvipdfm-x/cmap_read.c
@@ -401,8 +401,8 @@ do_cidchar (CMap *cmap, ifreader *input, int count)
}
-#define MATCH_NAME(t,n) (PST_NAMETYPE((t)) && !memcmp(pst_data_ptr((t)),(n),strlen((n))))
-#define MATCH_OP(t,n) (PST_UNKNOWNTYPE((t)) && !memcmp(pst_data_ptr((t)),(n),strlen((n))))
+#define MATCH_NAME(t,n) ((t) && PST_NAMETYPE((t)) && !strncmp(pst_data_ptr((t)),(n),strlen((n))+1))
+#define MATCH_OP(t,n) ((t) && PST_UNKNOWNTYPE((t)) && !strncmp(pst_data_ptr((t)),(n),strlen((n))+1))
static int
do_cidsysteminfo (CMap *cmap, ifreader *input)
--- a/source/texk/dvipdfm-x/t1_load.c
+++ b/source/texk/dvipdfm-x/t1_load.c
@@ -89,8 +89,8 @@ t1_decrypt (unsigned short key,
}
/* T1CRYPT */
-#define MATCH_NAME(t,n) ((t) && PST_NAMETYPE((t)) && !strncmp(pst_data_ptr((t)),(n),strlen((n))))
-#define MATCH_OP(t,n) ((t) && PST_UNKNOWNTYPE((t)) && !strncmp(pst_data_ptr((t)),(n),strlen((n))))
+#define MATCH_NAME(t,n) ((t) && PST_NAMETYPE((t)) && !strncmp(pst_data_ptr((t)),(n),strlen((n))+1))
+#define MATCH_OP(t,n) ((t) && PST_UNKNOWNTYPE((t)) && !strncmp(pst_data_ptr((t)),(n),strlen((n))+1))
#define RELEASE_TOK(t) if ((t) != NULL) {\
pst_release_obj((t));\
```
---
Masamichi Hosoda <trueroad at trueroad.jp>
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