52 lines
1.7 KiB
Diff
52 lines
1.7 KiB
Diff
|
This patch came from https://git.ghostscript.com/?p=mupdf.git;a=patch;h=cee7cefc610d42fd383b3c80c12cbc675443176a
|
||
|
|
and fixes CVE-2021-3407.
|
||
|
|
|
||
|
|
From cee7cefc610d42fd383b3c80c12cbc675443176a Mon Sep 17 00:00:00 2001
|
||
|
|
From: Robin Watts <Robin.Watts@artifex.com>
|
||
|
|
Date: Fri, 22 Jan 2021 17:05:15 +0000
|
||
|
|
Subject: [PATCH] Bug 703366: Fix double free of object during linearization.
|
||
|
|
|
||
|
|
This appears to happen because we parse an illegal object from
|
||
|
|
a broken file and assign it to object 0, which is defined to
|
||
|
|
be free.
|
||
|
|
|
||
|
|
Here, we fix the parsing code so this can't happen.
|
||
|
|
---
|
||
|
|
source/pdf/pdf-parse.c | 6 ++++++
|
||
|
|
source/pdf/pdf-xref.c | 2 ++
|
||
|
|
2 files changed, 8 insertions(+)
|
||
|
|
|
||
|
|
diff --git a/source/pdf/pdf-parse.c b/source/pdf/pdf-parse.c
|
||
|
|
index 7abc8c3d4..5761c3351 100644
|
||
|
|
--- a/source/pdf/pdf-parse.c
|
||
|
|
+++ b/source/pdf/pdf-parse.c
|
||
|
|
@@ -749,6 +749,12 @@ pdf_parse_ind_obj(fz_context *ctx, pdf_document *doc,
|
||
|
|
fz_throw(ctx, FZ_ERROR_SYNTAX, "expected generation number (%d ? obj)", num);
|
||
|
|
}
|
||
|
|
gen = buf->i;
|
||
|
|
+ if (gen < 0 || gen >= 65536)
|
||
|
|
+ {
|
||
|
|
+ if (try_repair)
|
||
|
|
+ *try_repair = 1;
|
||
|
|
+ fz_throw(ctx, FZ_ERROR_SYNTAX, "invalid generation number (%d)", gen);
|
||
|
|
+ }
|
||
|
|
|
||
|
|
tok = pdf_lex(ctx, file, buf);
|
||
|
|
if (tok != PDF_TOK_OBJ)
|
||
|
|
diff --git a/source/pdf/pdf-xref.c b/source/pdf/pdf-xref.c
|
||
|
|
index 1b2bdcd59..30197b4b8 100644
|
||
|
|
--- a/source/pdf/pdf-xref.c
|
||
|
|
+++ b/source/pdf/pdf-xref.c
|
||
|
|
@@ -1190,6 +1190,8 @@ pdf_read_new_xref(fz_context *ctx, pdf_document *doc, pdf_lexbuf *buf)
|
||
|
|
{
|
||
|
|
ofs = fz_tell(ctx, doc->file);
|
||
|
|
trailer = pdf_parse_ind_obj(ctx, doc, doc->file, buf, &num, &gen, &stm_ofs, NULL);
|
||
|
|
+ if (num == 0)
|
||
|
|
+ fz_throw(ctx, FZ_ERROR_GENERIC, "Trailer object number cannot be 0\n");
|
||
|
|
}
|
||
|
|
fz_catch(ctx)
|
||
|
|
{
|
||
|
|
--
|
||
|
|
2.17.1
|
||
|
|
|