Merge branch 'tls-fixes'

Jakub Kicinski says:

====================
tls: rx: strp: fix inline crypto offload

The local strparser version I added to TLS does not preserve
decryption status, which breaks inline crypto (NIC offload).
====================

Signed-off-by: David S. Miller <[email protected]>

Author: davem330

include/linux/skbuff.h

@@ -1587,6 +1587,16 @@ static inline void skb_copy_hash(struct sk_buff *to, const struct sk_buff *from)
 	to->l4_hash = from->l4_hash;
 };
 
+static inline int skb_cmp_decrypted(const struct sk_buff *skb1,
+				    const struct sk_buff *skb2)
+{
+#ifdef CONFIG_TLS_DEVICE
+	return skb2->decrypted - skb1->decrypted;
+#else
+	return 0;
+#endif
+}
+
 static inline void skb_copy_decrypted(struct sk_buff *to,
 				      const struct sk_buff *from)
 {

include/net/tls.h

@@ -126,6 +126,7 @@ struct tls_strparser {
 	u32 mark : 8;
 	u32 stopped : 1;
 	u32 copy_mode : 1;
+	u32 mixed_decrypted : 1;
 	u32 msg_ready : 1;
 
 	struct strp_msg stm;

net/tls/tls.h

@@ -167,6 +167,11 @@ static inline bool tls_strp_msg_ready(struct tls_sw_context_rx *ctx)
 	return ctx->strp.msg_ready;
 }
 
+static inline bool tls_strp_msg_mixed_decrypted(struct tls_sw_context_rx *ctx)
+{
+	return ctx->strp.mixed_decrypted;
+}
+
 #ifdef CONFIG_TLS_DEVICE
 int tls_device_init(void);
 void tls_device_cleanup(void);

net/tls/tls_device.c

@@ -1007,20 +1007,14 @@ int tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx)
 	struct tls_sw_context_rx *sw_ctx = tls_sw_ctx_rx(tls_ctx);
 	struct sk_buff *skb = tls_strp_msg(sw_ctx);
 	struct strp_msg *rxm = strp_msg(skb);
-	int is_decrypted = skb->decrypted;
-	int is_encrypted = !is_decrypted;
-	struct sk_buff *skb_iter;
-	int left;
-
-	left = rxm->full_len - skb->len;
-	/* Check if all the data is decrypted already */
-	skb_iter = skb_shinfo(skb)->frag_list;
-	while (skb_iter && left > 0) {
-		is_decrypted &= skb_iter->decrypted;
-		is_encrypted &= !skb_iter->decrypted;
-
-		left -= skb_iter->len;
-		skb_iter = skb_iter->next;
+	int is_decrypted, is_encrypted;
+
+	if (!tls_strp_msg_mixed_decrypted(sw_ctx)) {
+		is_decrypted = skb->decrypted;
+		is_encrypted = !is_decrypted;
+	} else {
+		is_decrypted = 0;
+		is_encrypted = 0;
 	}
 
 	trace_tls_device_decrypted(sk, tcp_sk(sk)->copied_seq - rxm->full_len,

net/tls/tls_strp.c

@@ -29,34 +29,50 @@ static void tls_strp_anchor_free(struct tls_strparser *strp)
 	struct skb_shared_info *shinfo = skb_shinfo(strp->anchor);
 
 	DEBUG_NET_WARN_ON_ONCE(atomic_read(&shinfo->dataref) != 1);
-	shinfo->frag_list = NULL;
+	if (!strp->copy_mode)
+		shinfo->frag_list = NULL;
 	consume_skb(strp->anchor);
 	strp->anchor = NULL;
 }
 
-/* Create a new skb with the contents of input copied to its page frags */
-static struct sk_buff *tls_strp_msg_make_copy(struct tls_strparser *strp)
+static struct sk_buff *
+tls_strp_skb_copy(struct tls_strparser *strp, struct sk_buff *in_skb,
+		  int offset, int len)
 {
-	struct strp_msg *rxm;
 	struct sk_buff *skb;
-	int i, err, offset;
+	int i, err;
 
-	skb = alloc_skb_with_frags(0, strp->stm.full_len, TLS_PAGE_ORDER,
+	skb = alloc_skb_with_frags(0, len, TLS_PAGE_ORDER,
 				   &err, strp->sk->sk_allocation);
 	if (!skb)
 		return NULL;
 
-	offset = strp->stm.offset;
 	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
 		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
 
-		WARN_ON_ONCE(skb_copy_bits(strp->anchor, offset,
+		WARN_ON_ONCE(skb_copy_bits(in_skb, offset,
 					   skb_frag_address(frag),
 					   skb_frag_size(frag)));
 		offset += skb_frag_size(frag);
 	}
 
-	skb_copy_header(skb, strp->anchor);
+	skb->len = len;
+	skb->data_len = len;
+	skb_copy_header(skb, in_skb);
+	return skb;
+}
+
+/* Create a new skb with the contents of input copied to its page frags */
+static struct sk_buff *tls_strp_msg_make_copy(struct tls_strparser *strp)
+{
+	struct strp_msg *rxm;
+	struct sk_buff *skb;
+
+	skb = tls_strp_skb_copy(strp, strp->anchor, strp->stm.offset,
+				strp->stm.full_len);
+	if (!skb)
+		return NULL;
+
 	rxm = strp_msg(skb);
 	rxm->offset = 0;
 	return skb;
@@ -180,22 +196,22 @@ static void tls_strp_flush_anchor_copy(struct tls_strparser *strp)
 	for (i = 0; i < shinfo->nr_frags; i++)
 		__skb_frag_unref(&shinfo->frags[i], false);
 	shinfo->nr_frags = 0;
+	if (strp->copy_mode) {
+		kfree_skb_list(shinfo->frag_list);
+		shinfo->frag_list = NULL;
+	}
 	strp->copy_mode = 0;
+	strp->mixed_decrypted = 0;
 }
 
-static int tls_strp_copyin(read_descriptor_t *desc, struct sk_buff *in_skb,
-			   unsigned int offset, size_t in_len)
+static int tls_strp_copyin_frag(struct tls_strparser *strp, struct sk_buff *skb,
+				struct sk_buff *in_skb, unsigned int offset,
+				size_t in_len)
 {
-	struct tls_strparser *strp = (struct tls_strparser *)desc->arg.data;
-	struct sk_buff *skb;
-	skb_frag_t *frag;
 	size_t len, chunk;
+	skb_frag_t *frag;
 	int sz;
 
-	if (strp->msg_ready)
-		return 0;
-
-	skb = strp->anchor;
 	frag = &skb_shinfo(skb)->frags[skb->len / PAGE_SIZE];
 
 	len = in_len;
@@ -208,19 +224,26 @@ static int tls_strp_copyin(read_descriptor_t *desc, struct sk_buff *in_skb,
 					   skb_frag_size(frag),
 					   chunk));
 
-		sz = tls_rx_msg_size(strp, strp->anchor);
-		if (sz < 0) {
-			desc->error = sz;
-			return 0;
-		}
-
-		/* We may have over-read, sz == 0 is guaranteed under-read */
-		if (sz > 0)
-			chunk =	min_t(size_t, chunk, sz - skb->len);
-
 		skb->len += chunk;
 		skb->data_len += chunk;
 		skb_frag_size_add(frag, chunk);
+
+		sz = tls_rx_msg_size(strp, skb);
+		if (sz < 0)
+			return sz;
+
+		/* We may have over-read, sz == 0 is guaranteed under-read */
+		if (unlikely(sz && sz < skb->len)) {
+			int over = skb->len - sz;
+
+			WARN_ON_ONCE(over > chunk);
+			skb->len -= over;
+			skb->data_len -= over;
+			skb_frag_size_add(frag, -over);
+
+			chunk -= over;
+		}
+
 		frag++;
 		len -= chunk;
 		offset += chunk;
@@ -247,15 +270,99 @@ static int tls_strp_copyin(read_descriptor_t *desc, struct sk_buff *in_skb,
 		offset += chunk;
 	}
 
-	if (strp->stm.full_len == skb->len) {
+read_done:
+	return in_len - len;
+}
+
+static int tls_strp_copyin_skb(struct tls_strparser *strp, struct sk_buff *skb,
+			       struct sk_buff *in_skb, unsigned int offset,
+			       size_t in_len)
+{
+	struct sk_buff *nskb, *first, *last;
+	struct skb_shared_info *shinfo;
+	size_t chunk;
+	int sz;
+
+	if (strp->stm.full_len)
+		chunk = strp->stm.full_len - skb->len;
+	else
+		chunk = TLS_MAX_PAYLOAD_SIZE + PAGE_SIZE;
+	chunk = min(chunk, in_len);
+
+	nskb = tls_strp_skb_copy(strp, in_skb, offset, chunk);
+	if (!nskb)
+		return -ENOMEM;
+
+	shinfo = skb_shinfo(skb);
+	if (!shinfo->frag_list) {
+		shinfo->frag_list = nskb;
+		nskb->prev = nskb;
+	} else {
+		first = shinfo->frag_list;
+		last = first->prev;
+		last->next = nskb;
+		first->prev = nskb;
+	}
+
+	skb->len += chunk;
+	skb->data_len += chunk;
+
+	if (!strp->stm.full_len) {
+		sz = tls_rx_msg_size(strp, skb);
+		if (sz < 0)
+			return sz;
+
+		/* We may have over-read, sz == 0 is guaranteed under-read */
+		if (unlikely(sz && sz < skb->len)) {
+			int over = skb->len - sz;
+
+			WARN_ON_ONCE(over > chunk);
+			skb->len -= over;
+			skb->data_len -= over;
+			__pskb_trim(nskb, nskb->len - over);
+
+			chunk -= over;
+		}
+
+		strp->stm.full_len = sz;
+	}
+
+	return chunk;
+}
+
+static int tls_strp_copyin(read_descriptor_t *desc, struct sk_buff *in_skb,
+			   unsigned int offset, size_t in_len)
+{
+	struct tls_strparser *strp = (struct tls_strparser *)desc->arg.data;
+	struct sk_buff *skb;
+	int ret;
+
+	if (strp->msg_ready)
+		return 0;
+
+	skb = strp->anchor;
+	if (!skb->len)
+		skb_copy_decrypted(skb, in_skb);
+	else
+		strp->mixed_decrypted |= !!skb_cmp_decrypted(skb, in_skb);
+
+	if (IS_ENABLED(CONFIG_TLS_DEVICE) && strp->mixed_decrypted)
+		ret = tls_strp_copyin_skb(strp, skb, in_skb, offset, in_len);
+	else
+		ret = tls_strp_copyin_frag(strp, skb, in_skb, offset, in_len);
+	if (ret < 0) {
+		desc->error = ret;
+		ret = 0;
+	}
+
+	if (strp->stm.full_len && strp->stm.full_len == skb->len) {
 		desc->count = 0;
 
 		strp->msg_ready = 1;
 		tls_rx_msg_ready(strp);
 	}
 
-read_done:
-	return in_len - len;
+	return ret;
 }
 
 static int tls_strp_read_copyin(struct tls_strparser *strp)
@@ -315,22 +422,28 @@ static int tls_strp_read_copy(struct tls_strparser *strp, bool qshort)
 	return 0;
 }
 
-static bool tls_strp_check_no_dup(struct tls_strparser *strp)
+static bool tls_strp_check_queue_ok(struct tls_strparser *strp)
 {
 	unsigned int len = strp->stm.offset + strp->stm.full_len;
-	struct sk_buff *skb;
+	struct sk_buff *first, *skb;
 	u32 seq;
 
-	skb = skb_shinfo(strp->anchor)->frag_list;
-	seq = TCP_SKB_CB(skb)->seq;
+	first = skb_shinfo(strp->anchor)->frag_list;
+	skb = first;
+	seq = TCP_SKB_CB(first)->seq;
 
+	/* Make sure there's no duplicate data in the queue,
+	 * and the decrypted status matches.
+	 */
 	while (skb->len < len) {
 		seq += skb->len;
 		len -= skb->len;
 		skb = skb->next;
 
 		if (TCP_SKB_CB(skb)->seq != seq)
 			return false;
+		if (skb_cmp_decrypted(first, skb))
+			return false;
 	}
 
 	return true;
@@ -411,7 +524,7 @@ static int tls_strp_read_sock(struct tls_strparser *strp)
 			return tls_strp_read_copy(strp, true);
 	}
 
-	if (!tls_strp_check_no_dup(strp))
+	if (!tls_strp_check_queue_ok(strp))
 		return tls_strp_read_copy(strp, false);
 
 	strp->msg_ready = 1;

net/tls/tls_sw.c

@@ -2304,10 +2304,14 @@ static void tls_data_ready(struct sock *sk)
 	struct tls_context *tls_ctx = tls_get_ctx(sk);
 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
 	struct sk_psock *psock;
+	gfp_t alloc_save;
 
 	trace_sk_data_ready(sk);
 
+	alloc_save = sk->sk_allocation;
+	sk->sk_allocation = GFP_ATOMIC;
 	tls_strp_data_ready(&ctx->strp);
+	sk->sk_allocation = alloc_save;
 
 	psock = sk_psock_get(sk);
 	if (psock) {