From: Ziyang Xuan william.xuanziyang@huawei.com
[ Upstream commit 9381fe8c849cfbe50245ac01fc077554f6eaa0e2 ]
The memory size of tls_ctx->rx.iv for AES128-CCM is 12 setting in tls_set_sw_offload(). The return value of crypto_aead_ivsize() for "ccm(aes)" is 16. So memcpy() require 16 bytes from 12 bytes memory space will trigger slab-out-of-bounds bug as following:
================================================================== BUG: KASAN: slab-out-of-bounds in decrypt_internal+0x385/0xc40 [tls] Read of size 16 at addr ffff888114e84e60 by task tls/10911
Call Trace: <TASK> dump_stack_lvl+0x34/0x44 print_report.cold+0x5e/0x5db ? decrypt_internal+0x385/0xc40 [tls] kasan_report+0xab/0x120 ? decrypt_internal+0x385/0xc40 [tls] kasan_check_range+0xf9/0x1e0 memcpy+0x20/0x60 decrypt_internal+0x385/0xc40 [tls] ? tls_get_rec+0x2e0/0x2e0 [tls] ? process_rx_list+0x1a5/0x420 [tls] ? tls_setup_from_iter.constprop.0+0x2e0/0x2e0 [tls] decrypt_skb_update+0x9d/0x400 [tls] tls_sw_recvmsg+0x3c8/0xb50 [tls]
Allocated by task 10911: kasan_save_stack+0x1e/0x40 __kasan_kmalloc+0x81/0xa0 tls_set_sw_offload+0x2eb/0xa20 [tls] tls_setsockopt+0x68c/0x700 [tls] __sys_setsockopt+0xfe/0x1b0
Replace the crypto_aead_ivsize() with prot->iv_size + prot->salt_size when memcpy() iv value in TLS_1_3_VERSION scenario.
Fixes: f295b3ae9f59 ("net/tls: Add support of AES128-CCM based ciphers") Signed-off-by: Ziyang Xuan william.xuanziyang@huawei.com Reviewed-by: Jakub Kicinski kuba@kernel.org Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/tls/tls_sw.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index bd96ec26f4f9..794ef3b3d7d4 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -1483,7 +1483,7 @@ static int decrypt_internal(struct sock *sk, struct sk_buff *skb, if (prot->version == TLS_1_3_VERSION || prot->cipher_type == TLS_CIPHER_CHACHA20_POLY1305) memcpy(iv + iv_offset, tls_ctx->rx.iv, - crypto_aead_ivsize(ctx->aead_recv)); + prot->iv_size + prot->salt_size); else memcpy(iv + iv_offset, tls_ctx->rx.iv, prot->salt_size);