summaryrefslogtreecommitdiff
path: root/src/lib/lzma.c
diff options
context:
space:
mode:
authorHung-Te Lin <hungte@chromium.org>2013-01-31 12:14:46 +0800
committerRonald G. Minnich <rminnich@gmail.com>2013-02-01 06:15:49 +0100
commitd51557ade2a9f29cbb4e0f38d5a4920b42486168 (patch)
tree970bb9b9100e021bd7f626210e24fc65c7af3d23 /src/lib/lzma.c
parent05dccae75df4ed0c6a75867a89cf1a4055507e28 (diff)
downloadcoreboot-d51557ade2a9f29cbb4e0f38d5a4920b42486168.tar.xz
lib: Prevent unaligned memory access and fix endianess in LZMA decode library.
LZMA decode library used to retrieve output size by: outSize = *(UInt32 *)(src + LZMA_PROPERTIES_SIZE); 'src' is aligned but LZMA_PROPERTIES_SIZE may refer to an unaligned address like src+5, and using that as integer pointer may fail on platforms like ARM. Also this will fail on systems using big-endian (outSize was encoded in little-endian). To fix this, reconstruct outSize in little-endian way. Change-Id: If678e735cb270c3e5e29f36f1fad318096bf7d59 Signed-off-by: Hung-Te Lin <hungte@chromium.org> Reviewed-on: http://review.coreboot.org/2246 Tested-by: build bot (Jenkins) Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Diffstat (limited to 'src/lib/lzma.c')
-rw-r--r--src/lib/lzma.c8
1 files changed, 7 insertions, 1 deletions
diff --git a/src/lib/lzma.c b/src/lib/lzma.c
index f0b88c12e2..cd60b3f3b2 100644
--- a/src/lib/lzma.c
+++ b/src/lib/lzma.c
@@ -29,9 +29,15 @@ unsigned long ulzma(unsigned char * src, unsigned char * dst)
#endif
/* in pre-ram, it must go on the stack */
unsigned char scratchpad[15980];
+ unsigned char *cp;
memcpy(properties, src, LZMA_PROPERTIES_SIZE);
- outSize = *(UInt32 *)(src + LZMA_PROPERTIES_SIZE);
+ /* The outSize in LZMA stream is a 64bit integer stored in little-endian
+ * (ref: lzma.cc@LZMACompress: put_64). To prevent accessing by
+ * unaligned memory address and to load in correct endianess, read each
+ * byte and re-costruct. */
+ cp = src + LZMA_PROPERTIES_SIZE;
+ outSize = cp[3] << 24 | cp[2] << 16 | cp[1] << 8 | cp[0];
if (LzmaDecodeProperties(&state.Properties, properties, LZMA_PROPERTIES_SIZE) != LZMA_RESULT_OK) {
printk(BIOS_WARNING, "lzma: Incorrect stream properties.\n");
return 0;