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.g...@nxp.com> --- Changes since v1: - Added 'Fixes:' tag. - Marking that patch applies to both 'net-next' & 'net' branches - Resending after correcting system time. - No code changes as such net/tls/tls_sw.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index be4f2e990f9f..2dad3dc7be60 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -263,6 +263,9 @@ 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; } @@ -276,6 +279,9 @@ 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; } -- 2.13.6