1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
|
From 69b91f7466a5ad5fb85039a5b4118efb77ad6347 Mon Sep 17 00:00:00 2001
From: Darren Kenny <darren.kenny@oracle.com>
Date: Wed, 4 Nov 2020 14:43:44 +0000
Subject: [PATCH] video/fb/video_fb: Fix multiple integer overflows
The calculation of the unsigned 64-bit value is being generated by
multiplying 2, signed or unsigned, 32-bit integers which may overflow
before promotion to unsigned 64-bit. Fix all of them.
Fixes: CID 73703, CID 73767, CID 73833
Signed-off-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Upstream-Status: Backport [https://git.savannah.gnu.org/cgit/grub.git/commit/?id=08e098b1dbf01e96376f594b337491bc4cfa48dd]
Signed-off-by: Marta Rybczynska <marta.rybczynska@huawei.com>
---
grub-core/video/fb/video_fb.c | 52 ++++++++++++++++++++++++-----------
1 file changed, 36 insertions(+), 16 deletions(-)
diff --git a/grub-core/video/fb/video_fb.c b/grub-core/video/fb/video_fb.c
index 1a602c8..1c9a138 100644
--- a/grub-core/video/fb/video_fb.c
+++ b/grub-core/video/fb/video_fb.c
@@ -25,6 +25,7 @@
#include <grub/fbutil.h>
#include <grub/bitmap.h>
#include <grub/dl.h>
+#include <grub/safemath.h>
GRUB_MOD_LICENSE ("GPLv3+");
@@ -1417,15 +1418,23 @@ doublebuf_blit_update_screen (void)
{
if (framebuffer.current_dirty.first_line
<= framebuffer.current_dirty.last_line)
- grub_memcpy ((char *) framebuffer.pages[0]
- + framebuffer.current_dirty.first_line
- * framebuffer.back_target->mode_info.pitch,
- (char *) framebuffer.back_target->data
- + framebuffer.current_dirty.first_line
- * framebuffer.back_target->mode_info.pitch,
- framebuffer.back_target->mode_info.pitch
- * (framebuffer.current_dirty.last_line
- - framebuffer.current_dirty.first_line));
+ {
+ grub_size_t copy_size;
+
+ if (grub_sub (framebuffer.current_dirty.last_line,
+ framebuffer.current_dirty.first_line, ©_size) ||
+ grub_mul (framebuffer.back_target->mode_info.pitch, copy_size, ©_size))
+ {
+ /* Shouldn't happen, but if it does we've a bug. */
+ return GRUB_ERR_BUG;
+ }
+
+ grub_memcpy ((char *) framebuffer.pages[0] + framebuffer.current_dirty.first_line *
+ framebuffer.back_target->mode_info.pitch,
+ (char *) framebuffer.back_target->data + framebuffer.current_dirty.first_line *
+ framebuffer.back_target->mode_info.pitch,
+ copy_size);
+ }
framebuffer.current_dirty.first_line
= framebuffer.back_target->mode_info.height;
framebuffer.current_dirty.last_line = 0;
@@ -1439,7 +1448,7 @@ grub_video_fb_doublebuf_blit_init (struct grub_video_fbrender_target **back,
volatile void *framebuf)
{
grub_err_t err;
- grub_size_t page_size = mode_info.pitch * mode_info.height;
+ grub_size_t page_size = (grub_size_t) mode_info.pitch * mode_info.height;
framebuffer.offscreen_buffer = grub_zalloc (page_size);
if (! framebuffer.offscreen_buffer)
@@ -1482,12 +1491,23 @@ doublebuf_pageflipping_update_screen (void)
last_line = framebuffer.previous_dirty.last_line;
if (first_line <= last_line)
- grub_memcpy ((char *) framebuffer.pages[framebuffer.render_page]
- + first_line * framebuffer.back_target->mode_info.pitch,
- (char *) framebuffer.back_target->data
- + first_line * framebuffer.back_target->mode_info.pitch,
- framebuffer.back_target->mode_info.pitch
- * (last_line - first_line));
+ {
+ grub_size_t copy_size;
+
+ if (grub_sub (last_line, first_line, ©_size) ||
+ grub_mul (framebuffer.back_target->mode_info.pitch, copy_size, ©_size))
+ {
+ /* Shouldn't happen, but if it does we've a bug. */
+ return GRUB_ERR_BUG;
+ }
+
+ grub_memcpy ((char *) framebuffer.pages[framebuffer.render_page] + first_line *
+ framebuffer.back_target->mode_info.pitch,
+ (char *) framebuffer.back_target->data + first_line *
+ framebuffer.back_target->mode_info.pitch,
+ copy_size);
+ }
+
framebuffer.previous_dirty = framebuffer.current_dirty;
framebuffer.current_dirty.first_line
= framebuffer.back_target->mode_info.height;
|
