initrd: fix lz4 decompress with initrd

During testing initrd (>2G) support, find decompress/lz4 does not work
with initrd at all.

decompress_* should support:
1. inbuf[]/outbuf[] for kernel preboot.
2. inbuf[]/flush() for initramfs
3. fill()/flush() for initrd.

in the unlz4 does not handle case 3, as input len is passed as 0, and it
failed in first try.

Fix that add one extra if (fill) checking, and get out if EOF from the
fill().

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Kyungsik Lee <kyungsik.lee@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/lib/decompress_unlz4.c b/lib/decompress_unlz4.c
index 7d1e83caf8ad8512c3a0d39e4f5e5b5c39de619f..3ad7f3954dfd23b27a87380e75d384f3056d609a 100644 (file)
--- a/lib/decompress_unlz4.c
+++ b/lib/decompress_unlz4.c
@@ -83,13 +83,20 @@ STATIC inline int INIT unlz4(u8 *input, int in_len,
        if (posp)
                *posp = 0;
 
-       if (fill)
-               fill(inp, 4);
+       if (fill) {
+               size = fill(inp, 4);
+               if (size < 4) {
+                       error("data corrupted");
+                       goto exit_2;
+               }
+       }
 
        chunksize = get_unaligned_le32(inp);
        if (chunksize == ARCHIVE_MAGICNUMBER) {
-               inp += 4;
-               size -= 4;
+               if (!fill) {
+                       inp += 4;
+                       size -= 4;
+               }
        } else {
                error("invalid header");
                goto exit_2;
@@ -100,29 +107,44 @@ STATIC inline int INIT unlz4(u8 *input, int in_len,
 
        for (;;) {
 
-               if (fill)
-                       fill(inp, 4);
+               if (fill) {
+                       size = fill(inp, 4);
+                       if (size == 0)
+                               break;
+                       if (size < 4) {
+                               error("data corrupted");
+                               goto exit_2;
+                       }
+               }
 
                chunksize = get_unaligned_le32(inp);
                if (chunksize == ARCHIVE_MAGICNUMBER) {
-                       inp += 4;
-                       size -= 4;
+                       if (!fill) {
+                               inp += 4;
+                               size -= 4;
+                       }
                        if (posp)
                                *posp += 4;
                        continue;
                }
-               inp += 4;
-               size -= 4;
+
 
                if (posp)
                        *posp += 4;
 
-               if (fill) {
+               if (!fill) {
+                       inp += 4;
+                       size -= 4;
+               } else {
                        if (chunksize > lz4_compressbound(uncomp_chunksize)) {
                                error("chunk length is longer than allocated");
                                goto exit_2;
                        }
-                       fill(inp, chunksize);
+                       size = fill(inp, chunksize);
+                       if (size < chunksize) {
+                               error("data corrupted");
+                               goto exit_2;
+                       }
                }
 #ifdef PREBOOT
                if (out_len >= uncomp_chunksize) {
@@ -149,18 +171,17 @@ STATIC inline int INIT unlz4(u8 *input, int in_len,
                if (posp)
                        *posp += chunksize;
 
-               size -= chunksize;
+               if (!fill) {
+                       size -= chunksize;
 
-               if (size == 0)
-                       break;
-               else if (size < 0) {
-                       error("data corrupted");
-                       goto exit_2;
+                       if (size == 0)
+                               break;
+                       else if (size < 0) {
+                               error("data corrupted");
+                               goto exit_2;
+                       }
+                       inp += chunksize;
                }
-
-               inp += chunksize;
-               if (fill)
-                       inp = inp_start;
        }
 
        ret = 0;