[PATCH 4.14 008/173] net/tls: Set count of SG entries if sk_alloc_sg returns -ENOSPC
From: Greg Kroah-Hartman
Date: Mon Sep 24 2018 - 08:13:01 EST
4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Vakul Garg <vakul.garg@xxxxxxx>
[ Upstream commit 52ea992cfac357b73180d5c051dca43bc8d20c2a ]
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: 3c4d7559159b ("tls: kernel TLS support")
Signed-off-by: Vakul Garg <vakul.garg@xxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/tls/tls_sw.c | 6 ++++++
1 file changed, 6 insertions(+)
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -170,6 +170,9 @@ static int alloc_encrypted_sg(struct soc
rc = alloc_sg(sk, len, ctx->sg_encrypted_data,
&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;
}
@@ -183,6 +186,9 @@ static int alloc_plaintext_sg(struct soc
&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;
}