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
|
From dad8f502974ed9ad0a70ae6820d17b4b142558fc Mon Sep 17 00:00:00 2001
From: Jonathan Bar Or <jonathanbaror@gmail.com>
Date: Thu, 23 Jan 2025 19:17:05 +0100
Subject: [PATCH] commands/read: Fix an integer overflow when supplying more
than 2^31 characters
The grub_getline() function currently has a signed integer variable "i"
that can be overflown when user supplies more than 2^31 characters.
It results in a memory corruption of the allocated line buffer as well
as supplying large negative values to grub_realloc().
Fixes: CVE-2025-0690
Reported-by: Jonathan Bar Or <jonathanbaror@gmail.com>
Signed-off-by: Jonathan Bar Or <jonathanbaror@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
CVE: CVE-2025-0690
Upstream-Status: Backport [https://git.savannah.gnu.org/cgit/grub.git/commit/?id=dad8f502974ed9ad0a70ae6820d17b4b142558fc]
Signed-off-by: Peter Marko <peter.marko@siemens.com>
---
grub-core/commands/read.c | 19 +++++++++++++++----
1 file changed, 15 insertions(+), 4 deletions(-)
diff --git a/grub-core/commands/read.c b/grub-core/commands/read.c
index 597c90706..8d72e45c9 100644
--- a/grub-core/commands/read.c
+++ b/grub-core/commands/read.c
@@ -25,6 +25,7 @@
#include <grub/types.h>
#include <grub/extcmd.h>
#include <grub/i18n.h>
+#include <grub/safemath.h>
GRUB_MOD_LICENSE ("GPLv3+");
@@ -37,13 +38,14 @@ static const struct grub_arg_option options[] =
static char *
grub_getline (int silent)
{
- int i;
+ grub_size_t i;
char *line;
char *tmp;
int c;
+ grub_size_t alloc_size;
i = 0;
- line = grub_malloc (1 + i + sizeof('\0'));
+ line = grub_malloc (1 + sizeof('\0'));
if (! line)
return NULL;
@@ -59,8 +61,17 @@ grub_getline (int silent)
line[i] = (char) c;
if (!silent)
grub_printf ("%c", c);
- i++;
- tmp = grub_realloc (line, 1 + i + sizeof('\0'));
+ if (grub_add (i, 1, &i))
+ {
+ grub_error (GRUB_ERR_OUT_OF_RANGE, N_("overflow is detected"));
+ return NULL;
+ }
+ if (grub_add (i, 1 + sizeof('\0'), &alloc_size))
+ {
+ grub_error (GRUB_ERR_OUT_OF_RANGE, N_("overflow is detected"));
+ return NULL;
+ }
+ tmp = grub_realloc (line, alloc_size);
if (! tmp)
{
grub_free (line);
|
