Commit 52ea992c authored Sep 06, 2018 by Vakul Garg Committed by David S. Miller Sep 09, 2018

net/tls: Set count of SG entries if sk_alloc_sg returns -ENOSPC



tls_sw_sendmsg() allocates plaintext and encrypted SG entries using
function sk_alloc_sg(). In case the number of SG entries hit
MAX_SKB_FRAGS, sk_alloc_sg() returns -ENOSPC and sets the variable for
current SG index to '0'. This leads to calling of function
tls_push_record() with 'sg_encrypted_num_elem = 0' and later causes
kernel crash. To fix this, set the number of SG elements to the number
of elements in plaintext/encrypted SG arrays in case sk_alloc_sg()
returns -ENOSPC.

Fixes: 3c4d7559 ("tls: kernel TLS support")
Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 0e1f4c76

net/tls/tls_sw.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -125,6 +125,9 @@ static int alloc_encrypted_sg(struct sock *sk, int len)
		&ctx->sg_encrypted_num_elem,
		&ctx->sg_encrypted_size, 0);

		if (rc == -ENOSPC)
		ctx->sg_encrypted_num_elem = ARRAY_SIZE(ctx->sg_encrypted_data);

		return rc;
		}

		@@ -138,6 +141,9 @@ static int alloc_plaintext_sg(struct sock *sk, int len)
		&ctx->sg_plaintext_num_elem, &ctx->sg_plaintext_size,
		tls_ctx->pending_open_record_frags);

		if (rc == -ENOSPC)
		ctx->sg_plaintext_num_elem = ARRAY_SIZE(ctx->sg_plaintext_data);

		return rc;
		}