2015-04-16 12:10:58

by Krzysztof Kolasa

[permalink] [raw]
Subject: [RESEND PATCH v3] lz4: fix system halted at boot kernel x86_64 compressed lz4

Decompression process ends with an error when loading 64bit lz4 kernel:

Decoding failed
-- System halted

This condition is not needed for 64bit kernel from the last
commit d5e7cafd69da ("LZ4 : fix the data abort issue")

if( ... ||
(op + COPYLENGTH) > oend)
goto _output_error

macro LZ4_SECURE_COPY() tests op and does not copy any data
when op exceeds the value, decompression process is continued.

added by analogy to lz4_uncompress_unknownoutputsize(...)

Signed-off-by: Krzysztof Kolasa <[email protected]>
---
lib/lz4/lz4_decompress.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/lib/lz4/lz4_decompress.c b/lib/lz4/lz4_decompress.c
index 26cc602..6d940c7 100644
--- a/lib/lz4/lz4_decompress.c
+++ b/lib/lz4/lz4_decompress.c
@@ -140,8 +140,12 @@ static int lz4_uncompress(const char *source, char *dest, int osize)
/* Error: request to write beyond destination buffer */
if (cpy > oend)
goto _output_error;
+#if LZ4_ARCH64
+ if ((ref + COPYLENGTH) > oend)
+#else
if ((ref + COPYLENGTH) > oend ||
(op + COPYLENGTH) > oend)
+#endif
goto _output_error;
LZ4_SECURECOPY(ref, op, (oend - COPYLENGTH));
while (op < cpy)
@@ -266,7 +270,13 @@ static int lz4_uncompress_unknownoutputsize(const char *source, char *dest,
if (cpy > oend - COPYLENGTH) {
if (cpy > oend)
goto _output_error; /* write outside of buf */
-
+#if LZ4_ARCH64
+ if ((ref + COPYLENGTH) > oend)
+#else
+ if ((ref + COPYLENGTH) > oend ||
+ (op + COPYLENGTH) > oend)
+#endif
+ goto _output_error;
LZ4_SECURECOPY(ref, op, (oend - COPYLENGTH));
while (op < cpy)
*op++ = *ref++;
--
2.4.0.rc2.dirty