From ccdb40048b2972f10bdc944913c0e0ee26b5d1f2 Mon Sep 17 00:00:00 2001 From: Albin Tonnerre Date: Fri, 23 Apr 2010 13:17:58 -0400 Subject: [PATCH] lib: fix the use of LZO to decompress initramfs images This patch fixes 2 issues with the LZO decompressor: - It doesn't handle the case where a block isn't compressed at all. In this case, calling lzo1x_decompress_safe will fail, so we need to just use memcpy() instead (the upstream LZO code does something similar) - Since commit 54291362d2a5738e1b0495df2abcb9e6b0563a3f ("initramfs: add missing decompressor error check") , the decompressor return code is checked in the init/initramfs.c The LZO decompressor didn't return the expected value, causing the initramfs code to falsely believe a decompression error occured Signed-off-by: Albin Tonnerre Tested-by: bert schulze Cc: "H. Peter Anvin" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/decompress_unlzo.c | 22 +++++++++++++++------- 1 file changed, 15 insertions(+), 7 deletions(-) diff --git a/lib/decompress_unlzo.c b/lib/decompress_unlzo.c index db521f4..bcb3a4b 100644 --- a/lib/decompress_unlzo.c +++ b/lib/decompress_unlzo.c @@ -97,7 +97,7 @@ STATIC inline int INIT unlzo(u8 *input, int in_len, u32 src_len, dst_len; size_t tmp; u8 *in_buf, *in_buf_save, *out_buf; - int obytes_processed = 0; + int ret = -1; set_error_fn(error_fn); @@ -174,15 +174,22 @@ STATIC inline int INIT unlzo(u8 *input, int in_len, /* decompress */ tmp = dst_len; - r = lzo1x_decompress_safe((u8 *) in_buf, src_len, + + /* When the input data is not compressed at all, + * lzo1x_decompress_safe will fail, so call memcpy() + * instead */ + if (unlikely(dst_len == src_len)) + memcpy(out_buf, in_buf, src_len); + else { + r = lzo1x_decompress_safe((u8 *) in_buf, src_len, out_buf, &tmp); - if (r != LZO_E_OK || dst_len != tmp) { - error("Compressed data violation"); - goto exit_2; + if (r != LZO_E_OK || dst_len != tmp) { + error("Compressed data violation"); + goto exit_2; + } } - obytes_processed += dst_len; if (flush) flush(out_buf, dst_len); if (output) @@ -196,6 +203,7 @@ STATIC inline int INIT unlzo(u8 *input, int in_len, in_buf += src_len; } + ret = 0; exit_2: if (!input) free(in_buf); @@ -203,7 +211,7 @@ exit_1: if (!output) free(out_buf); exit: - return obytes_processed; + return ret; } #define decompress unlzo -- 1.8.2.3