1 files changed, 108 insertions, 98 deletions

diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 85e848007f91..ebc13ebebddf 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -2378,35 +2378,51 @@ static inline void smb2_sg_set_buf(struct scatterlist *sg, const void *buf,
 	sg_set_page(sg, virt_to_page(buf), buflen, offset_in_page(buf));
 }
 
-/* Assumes:
- * rqst->rq_iov[0]  is transform header
- * rqst->rq_iov[1+] data to be encrypted/decrypted
+/* Assumes the first rqst has a transform header as the first iov.
+ * I.e.
+ * rqst[0].rq_iov[0]  is transform header
+ * rqst[0].rq_iov[1+] data to be encrypted/decrypted
+ * rqst[1+].rq_iov[0+] data to be encrypted/decrypted
  */
 static struct scatterlist *
-init_sg(struct smb_rqst *rqst, u8 *sign)
+init_sg(int num_rqst, struct smb_rqst *rqst, u8 *sign)
 {
-	unsigned int sg_len = rqst->rq_nvec + rqst->rq_npages + 1;
-	unsigned int assoc_data_len = sizeof(struct smb2_transform_hdr) - 20;
+	unsigned int sg_len;
 	struct scatterlist *sg;
 	unsigned int i;
 	unsigned int j;
+	unsigned int idx = 0;
+	int skip;
+
+	sg_len = 1;
+	for (i = 0; i < num_rqst; i++)
+		sg_len += rqst[i].rq_nvec + rqst[i].rq_npages;
 
 	sg = kmalloc_array(sg_len, sizeof(struct scatterlist), GFP_KERNEL);
 	if (!sg)
 		return NULL;
 
 	sg_init_table(sg, sg_len);
-	smb2_sg_set_buf(&sg[0], rqst->rq_iov[0].iov_base + 20, assoc_data_len);
-	for (i = 1; i < rqst->rq_nvec; i++)
-		smb2_sg_set_buf(&sg[i], rqst->rq_iov[i].iov_base,
-						rqst->rq_iov[i].iov_len);
-	for (j = 0; i < sg_len - 1; i++, j++) {
-		unsigned int len, offset;
+	for (i = 0; i < num_rqst; i++) {
+		for (j = 0; j < rqst[i].rq_nvec; j++) {
+			/*
+			 * The first rqst has a transform header where the
+			 * first 20 bytes are not part of the encrypted blob
+			 */
+			skip = (i == 0) && (j == 0) ? 20 : 0;
+			smb2_sg_set_buf(&sg[idx++],
+					rqst[i].rq_iov[j].iov_base + skip,
+					rqst[i].rq_iov[j].iov_len - skip);
+		}
+
+		for (j = 0; j < rqst[i].rq_npages; j++) {
+			unsigned int len, offset;
 
-		rqst_page_get_length(rqst, j, &len, &offset);
-		sg_set_page(&sg[i], rqst->rq_pages[j], len, offset);
+			rqst_page_get_length(&rqst[i], j, &len, &offset);
+			sg_set_page(&sg[idx++], rqst[i].rq_pages[j], len, offset);
+		}
 	}
-	smb2_sg_set_buf(&sg[sg_len - 1], sign, SMB2_SIGNATURE_SIZE);
+	smb2_sg_set_buf(&sg[idx], sign, SMB2_SIGNATURE_SIZE);
 	return sg;
 }
 
@@ -2438,10 +2454,11 @@ smb2_get_enc_key(struct TCP_Server_Info *server, __u64 ses_id, int enc, u8 *key)
  * untouched.
  */
 static int
-crypt_message(struct TCP_Server_Info *server, struct smb_rqst *rqst, int enc)
+crypt_message(struct TCP_Server_Info *server, int num_rqst,
+	      struct smb_rqst *rqst, int enc)
 {
 	struct smb2_transform_hdr *tr_hdr =
-			(struct smb2_transform_hdr *)rqst->rq_iov[0].iov_base;
+		(struct smb2_transform_hdr *)rqst[0].rq_iov[0].iov_base;
 	unsigned int assoc_data_len = sizeof(struct smb2_transform_hdr) - 20;
 	int rc = 0;
 	struct scatterlist *sg;
@@ -2492,7 +2509,7 @@ crypt_message(struct TCP_Server_Info *server, struct smb_rqst *rqst, int enc)
 		crypt_len += SMB2_SIGNATURE_SIZE;
 	}
 
-	sg = init_sg(rqst, sign);
+	sg = init_sg(num_rqst, rqst, sign);
 	if (!sg) {
 		cifs_dbg(VFS, "%s: Failed to init sg", __func__);
 		rc = -ENOMEM;
@@ -2529,103 +2546,98 @@ free_req:
 	return rc;
 }
 
+void
+smb3_free_compound_rqst(int num_rqst, struct smb_rqst *rqst)
+{
+	int i, j;
+
+	for (i = 0; i < num_rqst; i++) {
+		if (rqst[i].rq_pages) {
+			for (j = rqst[i].rq_npages - 1; j >= 0; j--)
+				put_page(rqst[i].rq_pages[j]);
+			kfree(rqst[i].rq_pages);
+		}
+	}
+}
+
+/*
+ * This function will initialize new_rq and encrypt the content.
+ * The first entry, new_rq[0], only contains a single iov which contains
+ * a smb2_transform_hdr and is pre-allocated by the caller.
+ * This function then populates new_rq[1+] with the content from olq_rq[0+].
+ *
+ * The end result is an array of smb_rqst structures where the first structure
+ * only contains a single iov for the transform header which we then can pass
+ * to crypt_message().
+ *
+ * new_rq[0].rq_iov[0] :  smb2_transform_hdr pre-allocated by the caller
+ * new_rq[1+].rq_iov[*] == old_rq[0+].rq_iov[*] : SMB2/3 requests
+ */
 static int
-smb3_init_transform_rq(struct TCP_Server_Info *server, struct smb_rqst *new_rq,
-		       struct smb_rqst *old_rq)
+smb3_init_transform_rq(struct TCP_Server_Info *server, int num_rqst,
+		       struct smb_rqst *new_rq, struct smb_rqst *old_rq)
 {
-	struct kvec *iov;
 	struct page **pages;
-	struct smb2_transform_hdr *tr_hdr;
-	unsigned int npages = old_rq->rq_npages;
-	unsigned int orig_len;
-	int i;
+	struct smb2_transform_hdr *tr_hdr = new_rq[0].rq_iov[0].iov_base;
+	unsigned int npages;
+	unsigned int orig_len = 0;
+	int i, j;
 	int rc = -ENOMEM;
 
-	pages = kmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
-	if (!pages)
-		return rc;
-
-	new_rq->rq_pages = pages;
-	new_rq->rq_offset = old_rq->rq_offset;
-	new_rq->rq_npages = old_rq->rq_npages;
-	new_rq->rq_pagesz = old_rq->rq_pagesz;
-	new_rq->rq_tailsz = old_rq->rq_tailsz;
-
-	for (i = 0; i < npages; i++) {
-		pages[i] = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
-		if (!pages[i])
-			goto err_free_pages;
-	}
-
-	iov = kmalloc_array(old_rq->rq_nvec + 1, sizeof(struct kvec),
-			    GFP_KERNEL);
-	if (!iov)
-		goto err_free_pages;
+	for (i = 1; i < num_rqst; i++) {
+		npages = old_rq[i - 1].rq_npages;
+		pages = kmalloc_array(npages, sizeof(struct page *),
+				      GFP_KERNEL);
+		if (!pages)
+			goto err_free;
+
+		new_rq[i].rq_pages = pages;
+		new_rq[i].rq_npages = npages;
+		new_rq[i].rq_offset = old_rq[i - 1].rq_offset;
+		new_rq[i].rq_pagesz = old_rq[i - 1].rq_pagesz;
+		new_rq[i].rq_tailsz = old_rq[i - 1].rq_tailsz;
+		new_rq[i].rq_iov = old_rq[i - 1].rq_iov;
+		new_rq[i].rq_nvec = old_rq[i - 1].rq_nvec;
+
+		orig_len += smb_rqst_len(server, &old_rq[i - 1]);
+
+		for (j = 0; j < npages; j++) {
+			pages[j] = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
+			if (!pages[j])
+				goto err_free;
+		}
 
-	/* copy all iovs from the old */
-	memcpy(&iov[1], &old_rq->rq_iov[0],
-				sizeof(struct kvec) * old_rq->rq_nvec);
+		/* copy pages form the old */
+		for (j = 0; j < npages; j++) {
+			char *dst, *src;
+			unsigned int offset, len;
 
-	new_rq->rq_iov = iov;
-	new_rq->rq_nvec = old_rq->rq_nvec + 1;
+			rqst_page_get_length(&new_rq[i], j, &len, &offset);
 
-	tr_hdr = kmalloc(sizeof(struct smb2_transform_hdr), GFP_KERNEL);
-	if (!tr_hdr)
-		goto err_free_iov;
+			dst = (char *) kmap(new_rq[i].rq_pages[j]) + offset;
+			src = (char *) kmap(old_rq[i - 1].rq_pages[j]) + offset;
 
-	orig_len = smb_rqst_len(server, old_rq);
+			memcpy(dst, src, len);
+			kunmap(new_rq[i].rq_pages[j]);
+			kunmap(old_rq[i - 1].rq_pages[j]);
+		}
+	}
 
-	/* fill the 2nd iov with a transform header */
+	/* fill the 1st iov with a transform header */
 	fill_transform_hdr(tr_hdr, orig_len, old_rq);
-	new_rq->rq_iov[0].iov_base = tr_hdr;
-	new_rq->rq_iov[0].iov_len = sizeof(struct smb2_transform_hdr);
-
-	/* copy pages form the old */
-	for (i = 0; i < npages; i++) {
-		char *dst, *src;
-		unsigned int offset, len;
-
-		rqst_page_get_length(new_rq, i, &len, &offset);
 
-		dst = (char *) kmap(new_rq->rq_pages[i]) + offset;
-		src = (char *) kmap(old_rq->rq_pages[i]) + offset;
-
-		memcpy(dst, src, len);
-		kunmap(new_rq->rq_pages[i]);
-		kunmap(old_rq->rq_pages[i]);
-	}
-
-	rc = crypt_message(server, new_rq, 1);
+	rc = crypt_message(server, num_rqst, new_rq, 1);
 	cifs_dbg(FYI, "encrypt message returned %d", rc);
 	if (rc)
-		goto err_free_tr_hdr;
+		goto err_free;
 
 	return rc;
 
-err_free_tr_hdr:
-	kfree(tr_hdr);
-err_free_iov:
-	kfree(iov);
-err_free_pages:
-	for (i = i - 1; i >= 0; i--)
-		put_page(pages[i]);
-	kfree(pages);
+err_free:
+	smb3_free_compound_rqst(num_rqst - 1, &new_rq[1]);
 	return rc;
 }
 
-static void
-smb3_free_transform_rq(struct smb_rqst *rqst)
-{
-	int i = rqst->rq_npages - 1;
-
-	for (; i >= 0; i--)
-		put_page(rqst->rq_pages[i]);
-	kfree(rqst->rq_pages);
-	/* free transform header */
-	kfree(rqst->rq_iov[0].iov_base);
-	kfree(rqst->rq_iov);
-}
-
 static int
 smb3_is_transform_hdr(void *buf)
 {
@@ -2655,7 +2667,7 @@ decrypt_raw_data(struct TCP_Server_Info *server, char *buf,
 	rqst.rq_pagesz = PAGE_SIZE;
 	rqst.rq_tailsz = (page_data_size % PAGE_SIZE) ? : PAGE_SIZE;
 
-	rc = crypt_message(server, &rqst, 0);
+	rc = crypt_message(server, 1, &rqst, 0);
 	cifs_dbg(FYI, "decrypt message returned %d\n", rc);
 
 	if (rc)
@@ -3302,7 +3314,6 @@ struct smb_version_operations smb30_operations = {
 	.fallocate = smb3_fallocate,
 	.enum_snapshots = smb3_enum_snapshots,
 	.init_transform_rq = smb3_init_transform_rq,
-	.free_transform_rq = smb3_free_transform_rq,
 	.is_transform_hdr = smb3_is_transform_hdr,
 	.receive_transform = smb3_receive_transform,
 	.get_dfs_refer = smb2_get_dfs_refer,
@@ -3408,7 +3419,6 @@ struct smb_version_operations smb311_operations = {
 	.fallocate = smb3_fallocate,
 	.enum_snapshots = smb3_enum_snapshots,
 	.init_transform_rq = smb3_init_transform_rq,
-	.free_transform_rq = smb3_free_transform_rq,
 	.is_transform_hdr = smb3_is_transform_hdr,
 	.receive_transform = smb3_receive_transform,
 	.get_dfs_refer = smb2_get_dfs_refer,