packages/squashfs-tools
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Fix CVE-2021-40153 CVE-2021-41072

Browse Source
This commit is contained in:
markeryang 2021-11-09 20:42:27 +08:00
parent d7b8644d36
commit 3c1478d7b7
7 changed files with 1089 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

264
0005-CVE-2021-40153.patch Normal file
View File

@ -0,0 +1,264 @@
From 39971ca17a17520cefeb84f65e028d5004a579b2 Mon Sep 17 00:00:00 2001
From: Phillip Lougher <phillip@squashfs.org.uk>
Date: Sat, 16 Jan 2021 20:08:55 +0000
Subject: [PATCH] Unsquashfs: fix write outside destination directory exploit
An issue on Github (https://github.com/plougher/squashfs-tools/issues/72)
shows how some specially crafted Squashfs filesystems containing
invalid file names (with '/' and ..) can cause Unsquashfs to write
files outside of the destination directory.
This commit fixes this exploit by checking all names for
validity.
In doing so I have also added checks for '.' and for names that
are shorter than they should be (names in the file system should
not have '\0' terminators).
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
---
squashfs-tools/Makefile | 5 ++-
squashfs-tools/unsquash-1.c | 9 +++++-
squashfs-tools/unsquash-1234.c | 58 ++++++++++++++++++++++++++++++++++
squashfs-tools/unsquash-2.c | 9 +++++-
squashfs-tools/unsquash-3.c | 9 +++++-
squashfs-tools/unsquash-4.c | 9 +++++-
squashfs-tools/unsquashfs.c | 4 +--
squashfs-tools/unsquashfs.h | 5 ++-
8 files changed, 100 insertions(+), 8 deletions(-)
create mode 100644 squashfs-tools/unsquash-1234.c
diff --git a/squashfs-tools/Makefile b/squashfs-tools/Makefile
index 46c0772..de06bb2 100644
--- a/squashfs-tools/Makefile
+++ b/squashfs-tools/Makefile
@@ -156,7 +156,8 @@ MKSQUASHFS_OBJS = mksquashfs.o read_fs.o action.o swap.o pseudo.o compressor.o \
caches-queues-lists.o
UNSQUASHFS_OBJS = unsquashfs.o unsquash-1.o unsquash-2.o unsquash-3.o \
- unsquash-4.o unsquash-123.o unsquash-34.o swap.o compressor.o unsquashfs_info.o
+ unsquash-4.o unsquash-123.o unsquash-34.o unsquash-1234.o swap.o \
+ compressor.o unsquashfs_info.o
CFLAGS ?= -O2
CFLAGS += $(EXTRA_CFLAGS) $(INCLUDEDIR) -D_FILE_OFFSET_BITS=64 \
@@ -350,6 +351,8 @@ unsquash-123.o: unsquashfs.h unsquash-123.c squashfs_fs.h squashfs_compat.h
unsquash-34.o: unsquashfs.h unsquash-34.c
+unsquash-1234.o: unsquash-1234.c
+
unsquashfs_xattr.o: unsquashfs_xattr.c unsquashfs.h squashfs_fs.h xattr.h
unsquashfs_info.o: unsquashfs.h squashfs_fs.h
diff --git a/squashfs-tools/unsquash-1.c b/squashfs-tools/unsquash-1.c
index 34eced3..28326cb 100644
--- a/squashfs-tools/unsquash-1.c
+++ b/squashfs-tools/unsquash-1.c
@@ -2,7 +2,7 @@
* Unsquash a squashfs filesystem. This is a highly compressed read only
* filesystem.
*
- * Copyright (c) 2009, 2010, 2011, 2012, 2019
+ * Copyright (c) 2009, 2010, 2011, 2012, 2019, 2021
* Phillip Lougher <phillip@squashfs.org.uk>
*
* This program is free software; you can redistribute it and/or
@@ -285,6 +285,13 @@ static struct dir *squashfs_opendir(unsigned int block_start, unsigned int offse
memcpy(dire->name, directory_table + bytes,
dire->size + 1);
dire->name[dire->size + 1] = '\0';
+
+ /* check name for invalid characters (i.e /, ., ..) */
+ if(check_name(dire->name, dire->size + 1) == FALSE) {
+ ERROR("File system corrupted: invalid characters in name\n");
+ goto corrupted;
+ }
+
TRACE("squashfs_opendir: directory entry %s, inode "
"%d:%d, type %d\n", dire->name,
dirh.start_block, dire->offset, dire->type);
diff --git a/squashfs-tools/unsquash-1234.c b/squashfs-tools/unsquash-1234.c
new file mode 100644
index 0000000..c2d4f42
--- /dev/null
+++ b/squashfs-tools/unsquash-1234.c
@@ -0,0 +1,58 @@
+/*
+ * Unsquash a squashfs filesystem. This is a highly compressed read only
+ * filesystem.
+ *
+ * Copyright (c) 2021
+ * Phillip Lougher <phillip@squashfs.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * unsquash-1234.c
+ *
+ * Helper functions used by unsquash-1, unsquash-2, unsquash-3 and
+ * unsquash-4.
+ */
+
+#define TRUE 1
+#define FALSE 0
+/*
+ * Check name for validity, name should not
+ * - be ".", "./", or
+ * - be "..", "../" or
+ * - have a "/" anywhere in the name, or
+ * - be shorter than the expected size
+ */
+int check_name(char *name, int size)
+{
+ char *start = name;
+
+ if(name[0] == '.') {
+ if(name[1] == '.')
+ name++;
+ if(name[1] == '/' || name[1] == '\0')
+ return FALSE;
+ }
+
+ while(name[0] != '/' && name[0] != '\0')
+ name ++;
+
+ if(name[0] == '/')
+ return FALSE;
+
+ if((name - start) != size)
+ return FALSE;
+
+ return TRUE;
+}
diff --git a/squashfs-tools/unsquash-2.c b/squashfs-tools/unsquash-2.c
index 4b3d767..474064e 100644
--- a/squashfs-tools/unsquash-2.c
+++ b/squashfs-tools/unsquash-2.c
@@ -2,7 +2,7 @@
* Unsquash a squashfs filesystem. This is a highly compressed read only
* filesystem.
*
- * Copyright (c) 2009, 2010, 2013, 2019
+ * Copyright (c) 2009, 2010, 2013, 2019, 2021
* Phillip Lougher <phillip@squashfs.org.uk>
*
* This program is free software; you can redistribute it and/or
@@ -386,6 +386,13 @@ static struct dir *squashfs_opendir(unsigned int block_start, unsigned int offse
memcpy(dire->name, directory_table + bytes,
dire->size + 1);
dire->name[dire->size + 1] = '\0';
+
+ /* check name for invalid characters (i.e /, ., ..) */
+ if(check_name(dire->name, dire->size + 1) == FALSE) {
+ ERROR("File system corrupted: invalid characters in name\n");
+ goto corrupted;
+ }
+
TRACE("squashfs_opendir: directory entry %s, inode "
"%d:%d, type %d\n", dire->name,
dirh.start_block, dire->offset, dire->type);
diff --git a/squashfs-tools/unsquash-3.c b/squashfs-tools/unsquash-3.c
index 02c31fc..65cfe4d 100644
--- a/squashfs-tools/unsquash-3.c
+++ b/squashfs-tools/unsquash-3.c
@@ -2,7 +2,7 @@
* Unsquash a squashfs filesystem. This is a highly compressed read only
* filesystem.
*
- * Copyright (c) 2009, 2010, 2011, 2012, 2013, 2019
+ * Copyright (c) 2009, 2010, 2011, 2012, 2013, 2019, 2021
* Phillip Lougher <phillip@squashfs.org.uk>
*
* This program is free software; you can redistribute it and/or
@@ -413,6 +413,13 @@ static struct dir *squashfs_opendir(unsigned int block_start, unsigned int offse
memcpy(dire->name, directory_table + bytes,
dire->size + 1);
dire->name[dire->size + 1] = '\0';
+
+ /* check name for invalid characters (i.e /, ., ..) */
+ if(check_name(dire->name, dire->size + 1) == FALSE) {
+ ERROR("File system corrupted: invalid characters in name\n");
+ goto corrupted;
+ }
+
TRACE("squashfs_opendir: directory entry %s, inode "
"%d:%d, type %d\n", dire->name,
dirh.start_block, dire->offset, dire->type);
diff --git a/squashfs-tools/unsquash-4.c b/squashfs-tools/unsquash-4.c
index 8475835..aa23a84 100644
--- a/squashfs-tools/unsquash-4.c
+++ b/squashfs-tools/unsquash-4.c
@@ -2,7 +2,7 @@
* Unsquash a squashfs filesystem. This is a highly compressed read only
* filesystem.
*
- * Copyright (c) 2009, 2010, 2011, 2012, 2013, 2019
+ * Copyright (c) 2009, 2010, 2011, 2012, 2013, 2019, 2021
* Phillip Lougher <phillip@squashfs.org.uk>
*
* This program is free software; you can redistribute it and/or
@@ -349,6 +349,13 @@ static struct dir *squashfs_opendir(unsigned int block_start, unsigned int offse
memcpy(dire->name, directory_table + bytes,
dire->size + 1);
dire->name[dire->size + 1] = '\0';
+
+ /* check name for invalid characters (i.e /, ., ..) */
+ if(check_name(dire->name, dire->size + 1) == FALSE) {
+ ERROR("File system corrupted: invalid characters in name\n");
+ goto corrupted;
+ }
+
TRACE("squashfs_opendir: directory entry %s, inode "
"%d:%d, type %d\n", dire->name,
dirh.start_block, dire->offset, dire->type);
diff --git a/squashfs-tools/unsquashfs.c b/squashfs-tools/unsquashfs.c
index 727f1d5..f1c3552 100644
--- a/squashfs-tools/unsquashfs.c
+++ b/squashfs-tools/unsquashfs.c
@@ -2610,8 +2610,8 @@ int parse_number(char *start, int *res)
#define VERSION() \
- printf("unsquashfs version 4.4 (2019/08/29)\n");\
- printf("copyright (C) 2019 Phillip Lougher "\
+ printf("unsquashfs version 4.4-git (2021/01/17)\n");\
+ printf("copyright (C) 2021 Phillip Lougher "\
"<phillip@squashfs.org.uk>\n\n");\
printf("This program is free software; you can redistribute it and/or"\
"\n");\
diff --git a/squashfs-tools/unsquashfs.h b/squashfs-tools/unsquashfs.h
index 934618b..db1da7a 100644
--- a/squashfs-tools/unsquashfs.h
+++ b/squashfs-tools/unsquashfs.h
@@ -4,7 +4,7 @@
* Unsquash a squashfs filesystem. This is a highly compressed read only
* filesystem.
*
- * Copyright (c) 2009, 2010, 2013, 2014, 2019
+ * Copyright (c) 2009, 2010, 2013, 2014, 2019, 2021
* Phillip Lougher <phillip@squashfs.org.uk>
*
* This program is free software; you can redistribute it and/or
@@ -261,4 +261,7 @@ extern int read_ids(int, long long, long long, unsigned int **);
/* unsquash-34.c */
extern long long *alloc_index_table(int);
+
+/* unsquash-1234.c */
+extern int check_name(char *, int);
#endif
--
2.23.0

112
0006-CVE-2021-41072.patch Normal file
View File

@ -0,0 +1,112 @@
From 80b8441a37fcf8bf07dacf24d9d6c6459a0f6e36 Mon Sep 17 00:00:00 2001
From: Phillip Lougher <phillip@squashfs.org.uk>
Date: Sun, 12 Sep 2021 19:58:19 +0100
Subject: [PATCH] unsquashfs: use squashfs_closedir() to delete directory
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
---
squashfs-tools/unsquash-1.c | 3 +--
squashfs-tools/unsquash-1234.c | 11 +++++++++--
squashfs-tools/unsquash-2.c | 3 +--
squashfs-tools/unsquash-3.c | 3 +--
squashfs-tools/unsquash-4.c | 3 +--
squashfs-tools/unsquashfs.c | 7 -------
squashfs-tools/unsquashfs.h | 1 +
7 files changed, 14 insertions(+), 17 deletions(-)
--- a/squashfs-tools/unsquash-1.c
+++ b/squashfs-tools/unsquash-1.c
@@ -316,8 +316,7 @@ static struct dir *squashfs_opendir(unsi
return dir;
corrupted:
- free(dir->dirs);
- free(dir);
+ squashfs_closedir(dir);
return NULL;
}
--- a/squashfs-tools/unsquash-1234.c
+++ b/squashfs-tools/unsquash-1234.c
@@ -25,8 +25,8 @@
* unsquash-4.
*/
-#define TRUE 1
-#define FALSE 0
+#include "unsquashfs.h"
+
/*
* Check name for validity, name should not
* - be ".", "./", or
@@ -56,3 +56,10 @@ int check_name(char *name, int size)
return TRUE;
}
+
+
+void squashfs_closedir(struct dir *dir)
+{
+ free(dir->dirs);
+ free(dir);
+}
--- a/squashfs-tools/unsquash-2.c
+++ b/squashfs-tools/unsquash-2.c
@@ -417,8 +417,7 @@ static struct dir *squashfs_opendir(unsi
return dir;
corrupted:
- free(dir->dirs);
- free(dir);
+ squashfs_closedir(dir);
return NULL;
}
--- a/squashfs-tools/unsquash-3.c
+++ b/squashfs-tools/unsquash-3.c
@@ -444,8 +444,7 @@ static struct dir *squashfs_opendir(unsi
return dir;
corrupted:
- free(dir->dirs);
- free(dir);
+ squashfs_closedir(dir);
return NULL;
}
--- a/squashfs-tools/unsquash-4.c
+++ b/squashfs-tools/unsquash-4.c
@@ -380,8 +380,7 @@ static struct dir *squashfs_opendir(unsi
return dir;
corrupted:
- free(dir->dirs);
- free(dir);
+ squashfs_closedir(dir);
return NULL;
}
--- a/squashfs-tools/unsquashfs.c
+++ b/squashfs-tools/unsquashfs.c
@@ -1290,13 +1290,6 @@ unsigned int *offset, unsigned int *type
}
-void squashfs_closedir(struct dir *dir)
-{
- free(dir->dirs);
- free(dir);
-}
-
-
char *get_component(char *target, char **targname)
{
char *start;
--- a/squashfs-tools/unsquashfs.h
+++ b/squashfs-tools/unsquashfs.h
@@ -264,4 +264,5 @@ extern long long *alloc_index_table(int)
/* unsquash-1234.c */
extern int check_name(char *, int);
+extern void squashfs_closedir(struct dir *);
#endif

87
0007-CVE-2021-41072.patch Normal file
View File

@ -0,0 +1,87 @@
From 1993a4e7aeda04962bf26e84c15fba8b58837e10 Mon Sep 17 00:00:00 2001
From: Phillip Lougher <phillip@squashfs.org.uk>
Date: Sun, 12 Sep 2021 20:09:13 +0100
Subject: [PATCH] unsquashfs: dynamically allocate name
Dynamically allocate name rather than store it
directly in structure.
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
---
squashfs-tools/unsquash-1.c | 2 +-
squashfs-tools/unsquash-1234.c | 5 +++++
squashfs-tools/unsquash-2.c | 2 +-
squashfs-tools/unsquash-3.c | 2 +-
squashfs-tools/unsquash-4.c | 2 +-
squashfs-tools/unsquashfs.h | 2 +-
6 files changed, 10 insertions(+), 5 deletions(-)
--- a/squashfs-tools/unsquash-1.c
+++ b/squashfs-tools/unsquash-1.c
@@ -303,7 +303,7 @@ static struct dir *squashfs_opendir(unsi
"realloc failed!\n");
dir->dirs = new_dir;
}
- strcpy(dir->dirs[dir->dir_count].name, dire->name);
+ dir->dirs[dir->dir_count].name = strdup(dire->name);
dir->dirs[dir->dir_count].start_block =
dirh.start_block;
dir->dirs[dir->dir_count].offset = dire->offset;
--- a/squashfs-tools/unsquash-1234.c
+++ b/squashfs-tools/unsquash-1234.c
@@ -60,6 +60,11 @@ int check_name(char *name, int size)
void squashfs_closedir(struct dir *dir)
{
+ int i;
+
+ for(i = 0; i < dir->dir_count; i++)
+ free(dir->dirs[i].name);
+
free(dir->dirs);
free(dir);
}
--- a/squashfs-tools/unsquash-2.c
+++ b/squashfs-tools/unsquash-2.c
@@ -404,7 +404,7 @@ static struct dir *squashfs_opendir(unsi
"realloc failed!\n");
dir->dirs = new_dir;
}
- strcpy(dir->dirs[dir->dir_count].name, dire->name);
+ dir->dirs[dir->dir_count].name = strdup(dire->name);
dir->dirs[dir->dir_count].start_block =
dirh.start_block;
dir->dirs[dir->dir_count].offset = dire->offset;
--- a/squashfs-tools/unsquash-3.c
+++ b/squashfs-tools/unsquash-3.c
@@ -431,7 +431,7 @@ static struct dir *squashfs_opendir(unsi
"realloc failed!\n");
dir->dirs = new_dir;
}
- strcpy(dir->dirs[dir->dir_count].name, dire->name);
+ dir->dirs[dir->dir_count].name = strdup(dire->name);
dir->dirs[dir->dir_count].start_block =
dirh.start_block;
dir->dirs[dir->dir_count].offset = dire->offset;
--- a/squashfs-tools/unsquash-4.c
+++ b/squashfs-tools/unsquash-4.c
@@ -367,7 +367,7 @@ static struct dir *squashfs_opendir(unsi
"realloc failed!\n");
dir->dirs = new_dir;
}
- strcpy(dir->dirs[dir->dir_count].name, dire->name);
+ dir->dirs[dir->dir_count].name = strdup(dire->name);
dir->dirs[dir->dir_count].start_block =
dirh.start_block;
dir->dirs[dir->dir_count].offset = dire->offset;
--- a/squashfs-tools/unsquashfs.h
+++ b/squashfs-tools/unsquashfs.h
@@ -165,7 +165,7 @@ struct queue {
#define DIR_ENT_SIZE 16
struct dir_ent {
- char name[SQUASHFS_NAME_LEN + 1];
+ char *name;
unsigned int start_block;
unsigned int offset;
unsigned int type;

306
0008-CVE-2021-41072.patch Normal file
View File

@ -0,0 +1,306 @@
From 9938154174756ee48a94ea0b076397a2944b028d Mon Sep 17 00:00:00 2001
From: Phillip Lougher <phillip@squashfs.org.uk>
Date: Sun, 12 Sep 2021 22:58:11 +0100
Subject: [PATCH] unsquashfs: use linked list to store directory names
This should bring higher performance, and it allows sorting
if necessary (1.x and 2.0 filesystems).
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
---
squashfs-tools/unsquash-1.c | 30 +++++++++++++++---------------
squashfs-tools/unsquash-1234.c | 12 ++++++++----
squashfs-tools/unsquash-2.c | 29 +++++++++++++++--------------
squashfs-tools/unsquash-3.c | 29 +++++++++++++++--------------
squashfs-tools/unsquash-4.c | 29 +++++++++++++++--------------
squashfs-tools/unsquashfs.c | 16 ++++++++++------
squashfs-tools/unsquashfs.h | 3 ++-
7 files changed, 80 insertions(+), 68 deletions(-)
--- a/squashfs-tools/unsquash-1.c
+++ b/squashfs-tools/unsquash-1.c
@@ -207,7 +207,7 @@ static struct dir *squashfs_opendir(unsi
long long start;
int bytes;
int dir_count, size;
- struct dir_ent *new_dir;
+ struct dir_ent *ent, *cur_ent = NULL;
struct dir *dir;
TRACE("squashfs_opendir: inode start block %d, offset %d\n",
@@ -220,7 +220,7 @@ static struct dir *squashfs_opendir(unsi
EXIT_UNSQUASH("squashfs_opendir: malloc failed!\n");
dir->dir_count = 0;
- dir->cur_entry = 0;
+ dir->cur_entry = NULL;
dir->mode = (*i)->mode;
dir->uid = (*i)->uid;
dir->guid = (*i)->gid;
@@ -295,19 +295,20 @@ static struct dir *squashfs_opendir(unsi
TRACE("squashfs_opendir: directory entry %s, inode "
"%d:%d, type %d\n", dire->name,
dirh.start_block, dire->offset, dire->type);
- if((dir->dir_count % DIR_ENT_SIZE) == 0) {
- new_dir = realloc(dir->dirs, (dir->dir_count +
- DIR_ENT_SIZE) * sizeof(struct dir_ent));
- if(new_dir == NULL)
- EXIT_UNSQUASH("squashfs_opendir: "
- "realloc failed!\n");
- dir->dirs = new_dir;
- }
- dir->dirs[dir->dir_count].name = strdup(dire->name);
- dir->dirs[dir->dir_count].start_block =
- dirh.start_block;
- dir->dirs[dir->dir_count].offset = dire->offset;
- dir->dirs[dir->dir_count].type = dire->type;
+ ent = malloc(sizeof(struct dir_ent));
+ if(ent == NULL)
+ MEM_ERROR();
+
+ ent->name = strdup(dire->name);
+ ent->start_block = dirh.start_block;
+ ent->offset = dire->offset;
+ ent->type = dire->type;
+ ent->next = NULL;
+ if(cur_ent == NULL)
+ dir->dirs = ent;
+ else
+ cur_ent->next = ent;
+ cur_ent = ent;
dir->dir_count ++;
bytes += dire->size + 1;
}
--- a/squashfs-tools/unsquash-1234.c
+++ b/squashfs-tools/unsquash-1234.c
@@ -60,11 +60,15 @@ int check_name(char *name, int size)
void squashfs_closedir(struct dir *dir)
{
- int i;
+ struct dir_ent *ent = dir->dirs;
- for(i = 0; i < dir->dir_count; i++)
- free(dir->dirs[i].name);
+ while(ent) {
+ struct dir_ent *tmp = ent;
+
+ ent = ent->next;
+ free(tmp->name);
+ free(tmp);
+ }
- free(dir->dirs);
free(dir);
}
--- a/squashfs-tools/unsquash-2.c
+++ b/squashfs-tools/unsquash-2.c
@@ -308,7 +308,7 @@ static struct dir *squashfs_opendir(unsi
long long start;
int bytes;
int dir_count, size;
- struct dir_ent *new_dir;
+ struct dir_ent *ent, *cur_ent = NULL;
struct dir *dir;
TRACE("squashfs_opendir: inode start block %d, offset %d\n",
@@ -321,7 +321,7 @@ static struct dir *squashfs_opendir(unsi
EXIT_UNSQUASH("squashfs_opendir: malloc failed!\n");
dir->dir_count = 0;
- dir->cur_entry = 0;
+ dir->cur_entry = NULL;
dir->mode = (*i)->mode;
dir->uid = (*i)->uid;
dir->guid = (*i)->gid;
@@ -396,19 +396,20 @@ static struct dir *squashfs_opendir(unsi
TRACE("squashfs_opendir: directory entry %s, inode "
"%d:%d, type %d\n", dire->name,
dirh.start_block, dire->offset, dire->type);
- if((dir->dir_count % DIR_ENT_SIZE) == 0) {
- new_dir = realloc(dir->dirs, (dir->dir_count +
- DIR_ENT_SIZE) * sizeof(struct dir_ent));
- if(new_dir == NULL)
- EXIT_UNSQUASH("squashfs_opendir: "
- "realloc failed!\n");
- dir->dirs = new_dir;
- }
- dir->dirs[dir->dir_count].name = strdup(dire->name);
- dir->dirs[dir->dir_count].start_block =
- dirh.start_block;
- dir->dirs[dir->dir_count].offset = dire->offset;
- dir->dirs[dir->dir_count].type = dire->type;
+ ent = malloc(sizeof(struct dir_ent));
+ if(ent == NULL)
+ MEM_ERROR();
+
+ ent->name = strdup(dire->name);
+ ent->start_block = dirh.start_block;
+ ent->offset = dire->offset;
+ ent->type = dire->type;
+ ent->next = NULL;
+ if(cur_ent == NULL)
+ dir->dirs = ent;
+ else
+ cur_ent->next = ent;
+ cur_ent = ent;
dir->dir_count ++;
bytes += dire->size + 1;
}
--- a/squashfs-tools/unsquash-3.c
+++ b/squashfs-tools/unsquash-3.c
@@ -334,7 +334,7 @@ static struct dir *squashfs_opendir(unsi
long long start;
int bytes;
int dir_count, size;
- struct dir_ent *new_dir;
+ struct dir_ent *ent, *cur_ent = NULL;
struct dir *dir;
TRACE("squashfs_opendir: inode start block %d, offset %d\n",
@@ -347,7 +347,7 @@ static struct dir *squashfs_opendir(unsi
EXIT_UNSQUASH("squashfs_opendir: malloc failed!\n");
dir->dir_count = 0;
- dir->cur_entry = 0;
+ dir->cur_entry = NULL;
dir->mode = (*i)->mode;
dir->uid = (*i)->uid;
dir->guid = (*i)->gid;
@@ -423,19 +423,20 @@ static struct dir *squashfs_opendir(unsi
TRACE("squashfs_opendir: directory entry %s, inode "
"%d:%d, type %d\n", dire->name,
dirh.start_block, dire->offset, dire->type);
- if((dir->dir_count % DIR_ENT_SIZE) == 0) {
- new_dir = realloc(dir->dirs, (dir->dir_count +
- DIR_ENT_SIZE) * sizeof(struct dir_ent));
- if(new_dir == NULL)
- EXIT_UNSQUASH("squashfs_opendir: "
- "realloc failed!\n");
- dir->dirs = new_dir;
- }
- dir->dirs[dir->dir_count].name = strdup(dire->name);
- dir->dirs[dir->dir_count].start_block =
- dirh.start_block;
- dir->dirs[dir->dir_count].offset = dire->offset;
- dir->dirs[dir->dir_count].type = dire->type;
+ ent = malloc(sizeof(struct dir_ent));
+ if(ent == NULL)
+ MEM_ERROR();
+
+ ent->name = strdup(dire->name);
+ ent->start_block = dirh.start_block;
+ ent->offset = dire->offset;
+ ent->type = dire->type;
+ ent->next = NULL;
+ if(cur_ent == NULL)
+ dir->dirs = ent;
+ else
+ cur_ent->next = ent;
+ cur_ent = ent;
dir->dir_count ++;
bytes += dire->size + 1;
}
--- a/squashfs-tools/unsquash-4.c
+++ b/squashfs-tools/unsquash-4.c
@@ -281,7 +281,7 @@ static struct dir *squashfs_opendir(unsi
long long start;
long long bytes;
int dir_count, size;
- struct dir_ent *new_dir;
+ struct dir_ent *ent, *cur_ent = NULL;
struct dir *dir;
TRACE("squashfs_opendir: inode start block %d, offset %d\n",
@@ -294,7 +294,7 @@ static struct dir *squashfs_opendir(unsi
EXIT_UNSQUASH("squashfs_opendir: malloc failed!\n");
dir->dir_count = 0;
- dir->cur_entry = 0;
+ dir->cur_entry = NULL;
dir->mode = (*i)->mode;
dir->uid = (*i)->uid;
dir->guid = (*i)->gid;
@@ -359,19 +359,20 @@ static struct dir *squashfs_opendir(unsi
TRACE("squashfs_opendir: directory entry %s, inode "
"%d:%d, type %d\n", dire->name,
dirh.start_block, dire->offset, dire->type);
- if((dir->dir_count % DIR_ENT_SIZE) == 0) {
- new_dir = realloc(dir->dirs, (dir->dir_count +
- DIR_ENT_SIZE) * sizeof(struct dir_ent));
- if(new_dir == NULL)
- EXIT_UNSQUASH("squashfs_opendir: "
- "realloc failed!\n");
- dir->dirs = new_dir;
- }
- dir->dirs[dir->dir_count].name = strdup(dire->name);
- dir->dirs[dir->dir_count].start_block =
- dirh.start_block;
- dir->dirs[dir->dir_count].offset = dire->offset;
- dir->dirs[dir->dir_count].type = dire->type;
+ ent = malloc(sizeof(struct dir_ent));
+ if(ent == NULL)
+ MEM_ERROR();
+
+ ent->name = strdup(dire->name);
+ ent->start_block = dirh.start_block;
+ ent->offset = dire->offset;
+ ent->type = dire->type;
+ ent->next = NULL;
+ if(cur_ent == NULL)
+ dir->dirs = ent;
+ else
+ cur_ent->next = ent;
+ cur_ent = ent;
dir->dir_count ++;
bytes += dire->size + 1;
}
--- a/squashfs-tools/unsquashfs.c
+++ b/squashfs-tools/unsquashfs.c
@@ -1277,14 +1277,18 @@ failed:
int squashfs_readdir(struct dir *dir, char **name, unsigned int *start_block,
unsigned int *offset, unsigned int *type)
{
- if(dir->cur_entry == dir->dir_count)
+ if(dir->cur_entry == NULL)
+ dir->cur_entry = dir->dirs;
+ else
+ dir->cur_entry = dir->cur_entry->next;
+
+ if(dir->cur_entry == NULL)
return FALSE;
- *name = dir->dirs[dir->cur_entry].name;
- *start_block = dir->dirs[dir->cur_entry].start_block;
- *offset = dir->dirs[dir->cur_entry].offset;
- *type = dir->dirs[dir->cur_entry].type;
- dir->cur_entry ++;
+ *name = dir->cur_entry->name;
+ *start_block = dir->cur_entry->start_block;
+ *offset = dir->cur_entry->offset;
+ *type = dir->cur_entry->type;
return TRUE;
}
--- a/squashfs-tools/unsquashfs.h
+++ b/squashfs-tools/unsquashfs.h
@@ -169,17 +169,18 @@ struct dir_ent {
unsigned int start_block;
unsigned int offset;
unsigned int type;
+ struct dir_ent *next;
};
struct dir {
int dir_count;
- int cur_entry;
unsigned int mode;
uid_t uid;
gid_t guid;
unsigned int mtime;
unsigned int xattr;
struct dir_ent *dirs;
+ struct dir_ent *cur_entry;
};
struct file_entry {

289
0009-CVE-2021-41072.patch Normal file
View File

@ -0,0 +1,289 @@
From e0485802ec72996c20026da320650d8362f555bd Mon Sep 17 00:00:00 2001
From: Phillip Lougher <phillip@squashfs.org.uk>
Date: Sun, 12 Sep 2021 23:50:06 +0100
Subject: [PATCH] Unsquashfs: additional write outside destination directory
exploit fix
An issue on github (https://github.com/plougher/squashfs-tools/issues/72)
showed how some specially crafted Squashfs filesystems containing
invalid file names (with '/' and '..') can cause Unsquashfs to write
files outside of the destination directory.
Since then it has been shown that specially crafted Squashfs filesystems
that contain a symbolic link pointing outside of the destination directory,
coupled with an identically named file within the same directory, can
cause Unsquashfs to write files outside of the destination directory.
Specifically the symbolic link produces a pathname pointing outside
of the destination directory, which is then followed when writing the
duplicate identically named file within the directory.
This commit fixes this exploit by explictly checking for duplicate
filenames within a directory. As directories in v2.1, v3.x, and v4.0
filesystems are sorted, this is achieved by checking for consecutively
identical filenames. Additionally directories are checked to
ensure they are sorted, to avoid attempts to evade the duplicate
check.
Version 1.x and 2.0 filesystems (where the directories were unsorted)
are sorted and then the above duplicate filename check is applied.
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
---
squashfs-tools/Makefile | 6 +-
squashfs-tools/unsquash-1.c | 6 ++
squashfs-tools/unsquash-12.c | 110 +++++++++++++++++++++++++++++++++
squashfs-tools/unsquash-1234.c | 21 +++++++
squashfs-tools/unsquash-2.c | 16 +++++
squashfs-tools/unsquash-3.c | 6 ++
squashfs-tools/unsquash-4.c | 6 ++
squashfs-tools/unsquashfs.h | 4 ++
8 files changed, 173 insertions(+), 2 deletions(-)
create mode 100644 squashfs-tools/unsquash-12.c
--- a/squashfs-tools/Makefile
+++ b/squashfs-tools/Makefile
@@ -156,8 +156,8 @@ MKSQUASHFS_OBJS = mksquashfs.o read_fs.o
caches-queues-lists.o
UNSQUASHFS_OBJS = unsquashfs.o unsquash-1.o unsquash-2.o unsquash-3.o \
- unsquash-4.o unsquash-123.o unsquash-34.o unsquash-1234.o swap.o \
- compressor.o unsquashfs_info.o
+ unsquash-4.o unsquash-123.o unsquash-34.o unsquash-1234.o unsquash-12.o \
+ swap.o compressor.o unsquashfs_info.o
CFLAGS ?= -O2
CFLAGS += $(EXTRA_CFLAGS) $(INCLUDEDIR) -D_FILE_OFFSET_BITS=64 \
@@ -353,6 +353,8 @@ unsquash-34.o: unsquashfs.h unsquash-34.
unsquash-1234.o: unsquash-1234.c
+unsquash-1234.o: unsquash-12.c
+
unsquashfs_xattr.o: unsquashfs_xattr.c unsquashfs.h squashfs_fs.h xattr.h
unsquashfs_info.o: unsquashfs.h squashfs_fs.h
--- a/squashfs-tools/unsquash-1.c
+++ b/squashfs-tools/unsquash-1.c
@@ -314,6 +314,12 @@ static struct dir *squashfs_opendir(unsi
}
}
+ /* check directory for duplicate names. Need to sort directory first */
+ sort_directory(dir);
+ if(check_directory(dir) == FALSE) {
+ ERROR("File system corrupted: directory has duplicate names\n");
+ goto corrupted;
+ }
return dir;
corrupted:
--- /dev/null
+++ b/squashfs-tools/unsquash-12.c
@@ -0,0 +1,110 @@
+/*
+ * Unsquash a squashfs filesystem. This is a highly compressed read only
+ * filesystem.
+ *
+ * Copyright (c) 2021
+ * Phillip Lougher <phillip@squashfs.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * unsquash-12.c
+ *
+ * Helper functions used by unsquash-1 and unsquash-2.
+ */
+
+#include "unsquashfs.h"
+
+/*
+ * Bottom up linked list merge sort.
+ *
+ */
+void sort_directory(struct dir *dir)
+{
+ struct dir_ent *cur, *l1, *l2, *next;
+ int len1, len2, stride = 1;
+
+ if(dir->dir_count < 2)
+ return;
+
+ /*
+ * We can consider our linked-list to be made up of stride length
+ * sublists. Eacn iteration around this loop merges adjacent
+ * stride length sublists into larger 2*stride sublists. We stop
+ * when stride becomes equal to the entire list.
+ *
+ * Initially stride = 1 (by definition a sublist of 1 is sorted), and
+ * these 1 element sublists are merged into 2 element sublists, which
+ * are then merged into 4 element sublists and so on.
+ */
+ do {
+ l2 = dir->dirs; /* head of current linked list */
+ cur = NULL; /* empty output list */
+
+ /*
+ * Iterate through the linked list, merging adjacent sublists.
+ * On each interation l2 points to the next sublist pair to be
+ * merged (if there's only one sublist left this is simply added
+ * to the output list)
+ */
+ while(l2) {
+ l1 = l2;
+ for(len1 = 0; l2 && len1 < stride; len1 ++, l2 = l2->next);
+ len2 = stride;
+
+ /*
+ * l1 points to first sublist.
+ * l2 points to second sublist.
+ * Merge them onto the output list
+ */
+ while(len1 && l2 && len2) {
+ if(strcmp(l1->name, l2->name) <= 0) {
+ next = l1;
+ l1 = l1->next;
+ len1 --;
+ } else {
+ next = l2;
+ l2 = l2->next;
+ len2 --;
+ }
+
+ if(cur) {
+ cur->next = next;
+ cur = next;
+ } else
+ dir->dirs = cur = next;
+ }
+ /*
+ * One sublist is now empty, copy the other one onto the
+ * output list
+ */
+ for(; len1; len1 --, l1 = l1->next) {
+ if(cur) {
+ cur->next = l1;
+ cur = l1;
+ } else
+ dir->dirs = cur = l1;
+ }
+ for(; l2 && len2; len2 --, l2 = l2->next) {
+ if(cur) {
+ cur->next = l2;
+ cur = l2;
+ } else
+ dir->dirs = cur = l2;
+ }
+ }
+ cur->next = NULL;
+ stride = stride << 1;
+ } while(stride < dir->dir_count);
+}
--- a/squashfs-tools/unsquash-1234.c
+++ b/squashfs-tools/unsquash-1234.c
@@ -72,3 +72,24 @@ void squashfs_closedir(struct dir *dir)
free(dir);
}
+
+
+/*
+ * Check directory for duplicate names. As the directory should be sorted,
+ * duplicates will be consecutive. Obviously we also need to check if the
+ * directory has been deliberately unsorted, to evade this check.
+ */
+int check_directory(struct dir *dir)
+{
+ int i;
+ struct dir_ent *ent;
+
+ if(dir->dir_count < 2)
+ return TRUE;
+
+ for(ent = dir->dirs, i = 0; i < dir->dir_count - 1; ent = ent->next, i++)
+ if(strcmp(ent->name, ent->next->name) >= 0)
+ return FALSE;
+
+ return TRUE;
+}
--- a/squashfs-tools/unsquash-2.c
+++ b/squashfs-tools/unsquash-2.c
@@ -29,6 +29,7 @@ static squashfs_fragment_entry_2 *fragme
static unsigned int *uid_table, *guid_table;
static char *inode_table, *directory_table;
static squashfs_operations ops;
+static int needs_sorting = FALSE;
static void read_block_list(unsigned int *block_list, char *block_ptr, int blocks)
{
@@ -415,6 +416,17 @@ static struct dir *squashfs_opendir(unsi
}
}
+ if(needs_sorting)
+ sort_directory(dir);
+
+ /* check directory for duplicate names and sorting */
+ if(check_directory(dir) == FALSE) {
+ if(needs_sorting)
+ ERROR("File system corrupted: directory has duplicate names\n");
+ else
+ ERROR("File system corrupted: directory has duplicate names or is unsorted\n");
+ goto corrupted;
+ }
return dir;
corrupted:
--- a/squashfs-tools/unsquash-3.c
+++ b/squashfs-tools/unsquash-3.c
@@ -442,6 +442,12 @@ static struct dir *squashfs_opendir(unsi
}
}
+ /* check directory for duplicate names and sorting */
+ if(check_directory(dir) == FALSE) {
+ ERROR("File system corrupted: directory has duplicate names or is unsorted\n");
+ goto corrupted;
+ }
+
return dir;
corrupted:
--- a/squashfs-tools/unsquash-4.c
+++ b/squashfs-tools/unsquash-4.c
@@ -378,6 +378,12 @@ static struct dir *squashfs_opendir(unsi
}
}
+ /* check directory for duplicate names and sorting */
+ if(check_directory(dir) == FALSE) {
+ ERROR("File system corrupted: directory has duplicate names or is unsorted\n");
+ goto corrupted;
+ }
+
return dir;
corrupted:
--- a/squashfs-tools/unsquashfs.h
+++ b/squashfs-tools/unsquashfs.h
@@ -266,4 +266,8 @@ extern long long *alloc_index_table(int)
/* unsquash-1234.c */
extern int check_name(char *, int);
extern void squashfs_closedir(struct dir *);
+extern int check_directory(struct dir *);
+
+/* unsquash-12.c */
+extern void sort_directory(struct dir *);
#endif

21
0010-CVE-2021-41072.patch Normal file
View File

@ -0,0 +1,21 @@
From 19fcc9365dcdb2c22d232d42d11012940df64b7c Mon Sep 17 00:00:00 2001
From: Phillip Lougher <phillip@squashfs.org.uk>
Date: Tue, 14 Sep 2021 05:41:27 +0100
Subject: [PATCH] Unsquashfs: Add makefile entry for unsquash-12.o
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
---
squashfs-tools/Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/squashfs-tools/Makefile
+++ b/squashfs-tools/Makefile
@@ -353,7 +353,7 @@ unsquash-34.o: unsquashfs.h unsquash-34.
unsquash-1234.o: unsquash-1234.c
-unsquash-1234.o: unsquash-12.c
+unsquash-12.o: unsquash-12.c unsquashfs.h
unsquashfs_xattr.o: unsquashfs_xattr.c unsquashfs.h squashfs_fs.h xattr.h

11
squashfs-tools.spec
View File

@ -1,6 +1,6 @@
Name: squashfs-tools Name: squashfs-tools
Version: 4.4 Version: 4.4
Release: 4 Release: 5
Summary: Utility for the squashfs filesystems Summary: Utility for the squashfs filesystems
License: GPLv2+ License: GPLv2+
URL: http://squashfs.sourceforge.net/ URL: http://squashfs.sourceforge.net/
@ -11,6 +11,12 @@ Patch1: 0001-Fix-typos-update-URLs-in-squashfs-tools-Makefile.patch
Patch2: 0002-Support-creating-sockets-in-unsquashfs.patch Patch2: 0002-Support-creating-sockets-in-unsquashfs.patch
Patch3: 0003-squashfs-tools-fix-build-failure-against-gcc-10.patch Patch3: 0003-squashfs-tools-fix-build-failure-against-gcc-10.patch
Patch4: 0004-xattr-Initialize-header-to-avoid-valgrind-warning.patch Patch4: 0004-xattr-Initialize-header-to-avoid-valgrind-warning.patch
Patch5: 0005-CVE-2021-40153.patch
Patch6: 0006-CVE-2021-41072.patch
Patch7: 0007-CVE-2021-41072.patch
Patch8: 0008-CVE-2021-41072.patch
Patch9: 0009-CVE-2021-41072.patch
Patch10: 0010-CVE-2021-41072.patch
BuildRequires: zlib-devel xz-devel libzstd-devel BuildRequires: zlib-devel xz-devel libzstd-devel
BuildRequires: lzo-devel libattr-devel lz4-devel gcc BuildRequires: lzo-devel libattr-devel lz4-devel gcc
@ -41,6 +47,9 @@ install -D -m 755 squashfs-tools/unsquashfs %{buildroot}%{_sbindir}/unsquashfs
%changelog %changelog
* Tue Nov 9 2021 yanglongkang <yanglongkang@huawei.com> - 4.4-5
- Fix CVE-2021-41053 CVE-2021-41072
* Fri Jul 30 2021 chenyanpanHW <chenyanpan@huawei.com> - 4.4-4 * Fri Jul 30 2021 chenyanpanHW <chenyanpan@huawei.com> - 4.4-4
- DESC: delete -S git from %autosetup, and delete BuildRequires git - DESC: delete -S git from %autosetup, and delete BuildRequires git