diff options
Diffstat (limited to 'poky/meta/recipes-bsp/u-boot/files/0001-fs-squashfs-Use-kcalloc-when-relevant.patch')
| -rw-r--r-- | poky/meta/recipes-bsp/u-boot/files/0001-fs-squashfs-Use-kcalloc-when-relevant.patch | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/poky/meta/recipes-bsp/u-boot/files/0001-fs-squashfs-Use-kcalloc-when-relevant.patch b/poky/meta/recipes-bsp/u-boot/files/0001-fs-squashfs-Use-kcalloc-when-relevant.patch new file mode 100644 index 0000000000..70fdbb1031 --- /dev/null +++ b/poky/meta/recipes-bsp/u-boot/files/0001-fs-squashfs-Use-kcalloc-when-relevant.patch @@ -0,0 +1,64 @@ +From 50d4b8b9effcf9dc9e5a90034de2f0003fb063f0 Mon Sep 17 00:00:00 2001 +From: Miquel Raynal <miquel.raynal@bootlin.com> +Date: Mon, 27 Jun 2022 12:20:03 +0200 +Subject: [PATCH] fs/squashfs: Use kcalloc when relevant + +A crafted squashfs image could embed a huge number of empty metadata +blocks in order to make the amount of malloc()'d memory overflow and be +much smaller than expected. Because of this flaw, any random code +positioned at the right location in the squashfs image could be memcpy'd +from the squashfs structures into U-Boot code location while trying to +access the rearmost blocks, before being executed. + +In order to prevent this vulnerability from being exploited in eg. a +secure boot environment, let's add a check over the amount of data +that is going to be allocated. Such a check could look like: + +if (!elem_size || n > SIZE_MAX / elem_size) + return NULL; + +The right way to do it would be to enhance the calloc() implementation +but this is quite an impacting change for such a small fix. Another +solution would be to add the check before the malloc call in the +squashfs implementation, but this does not look right. So for now, let's +use the kcalloc() compatibility function from Linux, which has this +check. + +Fixes: c5100613037 ("fs/squashfs: new filesystem") +Reported-by: Tatsuhiko Yasumatsu <Tatsuhiko.Yasumatsu@sony.com> +Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> +Tested-by: Tatsuhiko Yasumatsu <Tatsuhiko.Yasumatsu@sony.com> + +Upstream-Status: Backport [7f7fb9937c6cb49dd35153bd6708872b390b0a44] +CVE: CVE-2022-33967 + +Signed-off-by: Sakib Sajal <sakib.sajal@windriver.com> +--- + fs/squashfs/sqfs.c | 4 +++- + 1 file changed, 3 insertions(+), 1 deletion(-) + +diff --git a/fs/squashfs/sqfs.c b/fs/squashfs/sqfs.c +index e2d91c654c..10e63afbce 100644 +--- a/fs/squashfs/sqfs.c ++++ b/fs/squashfs/sqfs.c +@@ -13,6 +13,7 @@ + #include <linux/types.h> + #include <linux/byteorder/little_endian.h> + #include <linux/byteorder/generic.h> ++#include <linux/compat.h> + #include <memalign.h> + #include <stdlib.h> + #include <string.h> +@@ -725,7 +726,8 @@ static int sqfs_read_inode_table(unsigned char **inode_table) + goto free_itb; + } + +- *inode_table = malloc(metablks_count * SQFS_METADATA_BLOCK_SIZE); ++ *inode_table = kcalloc(metablks_count, SQFS_METADATA_BLOCK_SIZE, ++ GFP_KERNEL); + if (!*inode_table) { + ret = -ENOMEM; + goto free_itb; +-- +2.33.0 + |