|
 |
9723a8 |
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
|
|
|
9723a8 |
From: Daniel Axtens <dja@axtens.net>
|
|
|
9723a8 |
Date: Thu, 21 Jan 2021 18:35:22 +1100
|
|
|
9723a8 |
Subject: [PATCH] disk/lvm: Do not overread metadata
|
|
|
9723a8 |
|
|
|
9723a8 |
We could reach the end of valid metadata and not realize, leading to
|
|
|
9723a8 |
some buffer overreads. Check if we have reached the end and bail.
|
|
|
9723a8 |
|
|
|
9723a8 |
Signed-off-by: Daniel Axtens <dja@axtens.net>
|
|
|
9723a8 |
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
|
|
|
9723a8 |
---
|
|
|
9723a8 |
grub-core/disk/lvm.c | 31 +++++++++++++++++++++++++------
|
|
|
9723a8 |
1 file changed, 25 insertions(+), 6 deletions(-)
|
|
|
9723a8 |
|
|
|
9723a8 |
diff --git a/grub-core/disk/lvm.c b/grub-core/disk/lvm.c
|
|
|
b71686 |
index 03587e744..267be7b95 100644
|
|
|
9723a8 |
--- a/grub-core/disk/lvm.c
|
|
|
9723a8 |
+++ b/grub-core/disk/lvm.c
|
|
|
9723a8 |
@@ -314,17 +314,23 @@ error_parsing_metadata:
|
|
|
9723a8 |
while (1)
|
|
|
9723a8 |
{
|
|
|
9723a8 |
grub_ssize_t s;
|
|
|
9723a8 |
- while (grub_isspace (*p))
|
|
|
9723a8 |
+ while (grub_isspace (*p) && p < mda_end)
|
|
|
9723a8 |
p++;
|
|
|
9723a8 |
|
|
|
9723a8 |
+ if (p == mda_end)
|
|
|
9723a8 |
+ goto fail4;
|
|
|
9723a8 |
+
|
|
|
9723a8 |
if (*p == '}')
|
|
|
9723a8 |
break;
|
|
|
9723a8 |
|
|
|
9723a8 |
pv = grub_zalloc (sizeof (*pv));
|
|
|
9723a8 |
q = p;
|
|
|
9723a8 |
- while (*q != ' ')
|
|
|
9723a8 |
+ while (*q != ' ' && q < mda_end)
|
|
|
9723a8 |
q++;
|
|
|
9723a8 |
|
|
|
9723a8 |
+ if (q == mda_end)
|
|
|
9723a8 |
+ goto pvs_fail_noname;
|
|
|
9723a8 |
+
|
|
|
9723a8 |
s = q - p;
|
|
|
9723a8 |
pv->name = grub_malloc (s + 1);
|
|
|
9723a8 |
grub_memcpy (pv->name, p, s);
|
|
|
9723a8 |
@@ -367,6 +373,7 @@ error_parsing_metadata:
|
|
|
9723a8 |
continue;
|
|
|
9723a8 |
pvs_fail:
|
|
|
9723a8 |
grub_free (pv->name);
|
|
|
9723a8 |
+ pvs_fail_noname:
|
|
|
9723a8 |
grub_free (pv);
|
|
|
9723a8 |
goto fail4;
|
|
|
9723a8 |
}
|
|
|
9723a8 |
@@ -388,18 +395,24 @@ error_parsing_metadata:
|
|
|
9723a8 |
struct grub_diskfilter_segment *seg;
|
|
|
9723a8 |
int is_pvmove;
|
|
|
9723a8 |
|
|
|
9723a8 |
- while (grub_isspace (*p))
|
|
|
9723a8 |
+ while (grub_isspace (*p) && p < mda_end)
|
|
|
9723a8 |
p++;
|
|
|
9723a8 |
|
|
|
9723a8 |
+ if (p == mda_end)
|
|
|
9723a8 |
+ goto fail4;
|
|
|
9723a8 |
+
|
|
|
9723a8 |
if (*p == '}')
|
|
|
9723a8 |
break;
|
|
|
9723a8 |
|
|
|
9723a8 |
lv = grub_zalloc (sizeof (*lv));
|
|
|
9723a8 |
|
|
|
9723a8 |
q = p;
|
|
|
9723a8 |
- while (*q != ' ')
|
|
|
9723a8 |
+ while (*q != ' ' && q < mda_end)
|
|
|
9723a8 |
q++;
|
|
|
9723a8 |
|
|
|
9723a8 |
+ if (q == mda_end)
|
|
|
9723a8 |
+ goto lvs_fail;
|
|
|
9723a8 |
+
|
|
|
9723a8 |
s = q - p;
|
|
|
9723a8 |
lv->name = grub_strndup (p, s);
|
|
|
9723a8 |
if (!lv->name)
|
|
|
9723a8 |
@@ -572,9 +585,12 @@ error_parsing_metadata:
|
|
|
9723a8 |
if (p == NULL)
|
|
|
9723a8 |
goto lvs_segment_fail2;
|
|
|
9723a8 |
q = ++p;
|
|
|
9723a8 |
- while (*q != '"')
|
|
|
9723a8 |
+ while (q < mda_end && *q != '"')
|
|
|
9723a8 |
q++;
|
|
|
9723a8 |
|
|
|
9723a8 |
+ if (q == mda_end)
|
|
|
9723a8 |
+ goto lvs_segment_fail2;
|
|
|
9723a8 |
+
|
|
|
9723a8 |
s = q - p;
|
|
|
9723a8 |
|
|
|
9723a8 |
stripe->name = grub_malloc (s + 1);
|
|
|
9723a8 |
@@ -631,9 +647,12 @@ error_parsing_metadata:
|
|
|
9723a8 |
if (p == NULL)
|
|
|
9723a8 |
goto lvs_segment_fail2;
|
|
|
9723a8 |
q = ++p;
|
|
|
9723a8 |
- while (*q != '"')
|
|
|
9723a8 |
+ while (q < mda_end && *q != '"')
|
|
|
9723a8 |
q++;
|
|
|
9723a8 |
|
|
|
9723a8 |
+ if (q == mda_end)
|
|
|
9723a8 |
+ goto lvs_segment_fail2;
|
|
|
9723a8 |
+
|
|
|
9723a8 |
s = q - p;
|
|
|
9723a8 |
|
|
|
9723a8 |
lvname = grub_malloc (s + 1);
|