| From 39a759494f734c4cdc3e2b919671bfb3134b41ae Mon Sep 17 00:00:00 2001 |
| From: Paul Emge <paulemge@forallsecure.com> |
| Date: Mon, 8 Jul 2019 16:37:03 -0700 |
| Subject: [PATCH 1/9] CVE-2019-13103: disk: stop infinite recursion in DOS |
| Partitions |
| |
| part_get_info_extended and print_partition_extended can recurse infinitely |
| while parsing a self-referential filesystem or one with a silly number of |
| extended partitions. This patch adds a limit to the number of recursive |
| partitions. |
| |
| Signed-off-by: Paul Emge <paulemge@forallsecure.com> |
| |
| Upstream-Status: Backport[http://git.denx.de/?p=u-boot.git;a=commit; |
| h=232e2f4fd9a24bf08215ddc8c53ccadffc841fb5] |
| |
| CVE: CVE-2019-13103 |
| |
| Signed-off-by: Meng Li <Meng.Li@windriver.com> |
| --- |
| disk/part_dos.c | 18 ++++++++++++++++++ |
| 1 file changed, 18 insertions(+) |
| |
| diff --git a/disk/part_dos.c b/disk/part_dos.c |
| index 936cee0d36..aae9d95906 100644 |
| --- a/disk/part_dos.c |
| +++ b/disk/part_dos.c |
| @@ -23,6 +23,10 @@ |
| |
| #define DOS_PART_DEFAULT_SECTOR 512 |
| |
| +/* should this be configurable? It looks like it's not very common at all |
| + * to use large numbers of partitions */ |
| +#define MAX_EXT_PARTS 256 |
| + |
| /* Convert char[4] in little endian format to the host format integer |
| */ |
| static inline unsigned int le32_to_int(unsigned char *le32) |
| @@ -126,6 +130,13 @@ static void print_partition_extended(struct blk_desc *dev_desc, |
| dos_partition_t *pt; |
| int i; |
| |
| + /* set a maximum recursion level */ |
| + if (part_num > MAX_EXT_PARTS) |
| + { |
| + printf("** Nested DOS partitions detected, stopping **\n"); |
| + return; |
| + } |
| + |
| if (blk_dread(dev_desc, ext_part_sector, 1, (ulong *)buffer) != 1) { |
| printf ("** Can't read partition table on %d:" LBAFU " **\n", |
| dev_desc->devnum, ext_part_sector); |
| @@ -191,6 +202,13 @@ static int part_get_info_extended(struct blk_desc *dev_desc, |
| int i; |
| int dos_type; |
| |
| + /* set a maximum recursion level */ |
| + if (part_num > MAX_EXT_PARTS) |
| + { |
| + printf("** Nested DOS partitions detected, stopping **\n"); |
| + return -1; |
| + } |
| + |
| if (blk_dread(dev_desc, ext_part_sector, 1, (ulong *)buffer) != 1) { |
| printf ("** Can't read partition table on %d:" LBAFU " **\n", |
| dev_desc->devnum, ext_part_sector); |
| -- |
| 2.17.1 |
| |