1 files changed, 26 insertions, 6 deletions

diff --git a/fs/erofs/decompress.c b/fs/erofs/decompress.c
index 2be3b844cf..e04e5c34a8 100644
--- a/fs/erofs/decompress.c
+++ b/fs/erofs/decompress.c
@@ -15,8 +15,8 @@ static int z_erofs_decompress_lz4(struct z_erofs_decompress_req *rq)
 	if (erofs_sb_has_lz4_0padding()) {
 		support_0padding = true;
 
-		while (!src[inputmargin & ~PAGE_MASK])
-			if (!(++inputmargin & ~PAGE_MASK))
+		while (!src[inputmargin & (erofs_blksiz() - 1)])
+			if (!(++inputmargin & (erofs_blksiz() - 1)))
 				break;
 
 		if (inputmargin >= rq->inputsize)
@@ -40,6 +40,9 @@ static int z_erofs_decompress_lz4(struct z_erofs_decompress_req *rq)
 					  rq->decodedlength);
 
 	if (ret != (int)rq->decodedlength) {
+		erofs_err("failed to %s decompress %d in[%u, %u] out[%u]",
+			  rq->partial_decoding ? "partial" : "full",
+			  ret, rq->inputsize, inputmargin, rq->decodedlength);
 		ret = -EIO;
 		goto out;
 	}
@@ -58,13 +61,30 @@ out:
 
 int z_erofs_decompress(struct z_erofs_decompress_req *rq)
 {
-	if (rq->alg == Z_EROFS_COMPRESSION_SHIFTED) {
-		if (rq->inputsize != EROFS_BLKSIZ)
+	if (rq->alg == Z_EROFS_COMPRESSION_INTERLACED) {
+		unsigned int count, rightpart, skip;
+
+		/* XXX: should support inputsize >= erofs_blksiz() later */
+		if (rq->inputsize > erofs_blksiz())
 			return -EFSCORRUPTED;
 
-		DBG_BUGON(rq->decodedlength > EROFS_BLKSIZ);
-		DBG_BUGON(rq->decodedlength < rq->decodedskip);
+		if (rq->decodedlength > erofs_blksiz())
+			return -EFSCORRUPTED;
+
+		if (rq->decodedlength < rq->decodedskip)
+			return -EFSCORRUPTED;
 
+		count = rq->decodedlength - rq->decodedskip;
+		skip = erofs_blkoff(rq->interlaced_offset + rq->decodedskip);
+		rightpart = min(erofs_blksiz() - skip, count);
+		memcpy(rq->out, rq->in + skip, rightpart);
+		memcpy(rq->out + rightpart, rq->in, count - rightpart);
+		return 0;
+	} else if (rq->alg == Z_EROFS_COMPRESSION_SHIFTED) {
+		if (rq->decodedlength > rq->inputsize)
+			return -EFSCORRUPTED;
+
+		DBG_BUGON(rq->decodedlength < rq->decodedskip);
 		memcpy(rq->out, rq->in + rq->decodedskip,
 		       rq->decodedlength - rq->decodedskip);
 		return 0;