Blame SOURCES/0095-libblkid-fix-potential-bufer-overflows.patch

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From 55540ea3dfdc707dc998333fd0715549522464fb Mon Sep 17 00:00:00 2001
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From: Sebastian Krahmer <krahmer@suse.de>
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Date: Fri, 5 Dec 2014 10:06:42 +0100
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Subject: [PATCH 095/116] libblkid: fix potential bufer overflows
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While digging deeper into libblk probing, I found that some
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computations might wrap and allocate too few buffer space which then
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overflows. In particular on 32bit systems (chromebook) where size_t is
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32bit, this is problematic (for 64bit the result fits into the calloc
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size_t).
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Upstream: Upstream: https://github.com/karelzak/util-linux/commit/109df14fad4e9570e26950913ebace6c79289400
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Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=1392656
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Signed-off-by: Karel Zak <kzak@redhat.com>
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---
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 libblkid/src/partitions/gpt.c  | 12 ++++++++----
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 libblkid/src/probe.c           |  7 +++++++
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 libblkid/src/superblocks/zfs.c |  3 +++
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 3 files changed, 18 insertions(+), 4 deletions(-)
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diff --git a/libblkid/src/partitions/gpt.c b/libblkid/src/partitions/gpt.c
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index 6ab0dc6..e801ea3 100644
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--- a/libblkid/src/partitions/gpt.c
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+++ b/libblkid/src/partitions/gpt.c
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@@ -17,6 +17,7 @@
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 #include <stdlib.h>
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 #include <stdint.h>
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 #include <stddef.h>
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+#include <limits.h>
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 #include "partitions.h"
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 #include "crc32.h"
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@@ -266,14 +267,17 @@ static struct gpt_header *get_gpt_header(
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 		return NULL;
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 	}
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-	/* Size of blocks with GPT entries */
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-	esz = le32_to_cpu(h->num_partition_entries) *
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-			le32_to_cpu(h->sizeof_partition_entry);
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-	if (!esz) {
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+	if (le32_to_cpu(h->num_partition_entries) == 0 ||
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+	    le32_to_cpu(h->sizeof_partition_entry) == 0 ||
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+	    ULONG_MAX / le32_to_cpu(h->num_partition_entries) < le32_to_cpu(h->sizeof_partition_entry)) {
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 		DBG(LOWPROBE, blkid_debug("GPT entries undefined"));
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 		return NULL;
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 	}
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+	/* Size of blocks with GPT entries */
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+	esz = le32_to_cpu(h->num_partition_entries) *
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+			le32_to_cpu(h->sizeof_partition_entry);
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+
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 	/* The header seems valid, save it
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 	 * (we don't care about zeros in hdr->reserved2 area) */
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 	memcpy(hdr, h, sizeof(*h));
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diff --git a/libblkid/src/probe.c b/libblkid/src/probe.c
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index f9fab5b..9cf099a 100644
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--- a/libblkid/src/probe.c
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+++ b/libblkid/src/probe.c
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@@ -103,6 +103,7 @@
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 #include <inttypes.h>
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 #include <stdint.h>
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 #include <stdarg.h>
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+#include <limits.h>
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 #ifdef HAVE_LIBUUID
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 # include <uuid.h>
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@@ -565,6 +566,12 @@ unsigned char *blkid_probe_get_buffer(blkid_probe pr,
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 			return NULL;
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 		}
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+		/* someone trying to overflow some buffers? */
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+		if (len > ULONG_MAX - sizeof(struct blkid_bufinfo)) {
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+			errno = ENOMEM;
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+			return NULL;
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+		}
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+
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 		/* allocate info and space for data by why call */
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 		bf = calloc(1, sizeof(struct blkid_bufinfo) + len);
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 		if (!bf) {
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diff --git a/libblkid/src/superblocks/zfs.c b/libblkid/src/superblocks/zfs.c
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index 406ba2b..56ee472 100644
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--- a/libblkid/src/superblocks/zfs.c
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+++ b/libblkid/src/superblocks/zfs.c
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@@ -12,6 +12,7 @@
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 #include <errno.h>
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 #include <ctype.h>
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 #include <inttypes.h>
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+#include <limits.h>
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 #include "superblocks.h"
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@@ -108,6 +109,8 @@ static void zfs_extract_guid_name(blkid_probe pr, loff_t offset)
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 			nvs->nvs_type = be32_to_cpu(nvs->nvs_type);
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 			nvs->nvs_strlen = be32_to_cpu(nvs->nvs_strlen);
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+			if (nvs->nvs_strlen > UINT_MAX - sizeof(*nvs))
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+				break;
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 			avail -= nvs->nvs_strlen + sizeof(*nvs);
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 			nvdebug("nvstring: type %u string %*s\n", nvs->nvs_type,
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 				nvs->nvs_strlen, nvs->nvs_string);
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-- 
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2.9.3
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