From: Herbert Xu herbert@gondor.apana.org.au
commit c195d66a8a75c60515819b101975f38b7ec6577f upstream.
The iwd daemon uses libell which sets up the skcipher operation with two separate control messages. As the first control message is sent without MSG_MORE, it is interpreted as an empty request.
While libell should be fixed to use MSG_MORE where appropriate, this patch works around the bug in the kernel so that existing binaries continue to work.
We will print a warning however.
A separate issue is that the new kernel code no longer allows the control message to be sent twice within the same request. This restriction is obviously incompatible with what iwd was doing (first setting an IV and then sending the real control message). This patch changes the kernel so that this is explicitly allowed.
Reported-by: Caleb Jorden caljorden@hotmail.com Fixes: f3c802a1f300 ("crypto: algif_aead - Only wake up when...") Cc: stable@vger.kernel.org Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- crypto/af_alg.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-)
--- a/crypto/af_alg.c +++ b/crypto/af_alg.c @@ -16,6 +16,7 @@ #include <linux/module.h> #include <linux/net.h> #include <linux/rwsem.h> +#include <linux/sched.h> #include <linux/sched/signal.h> #include <linux/security.h>
@@ -847,9 +848,15 @@ int af_alg_sendmsg(struct socket *sock, }
lock_sock(sk); - if (ctx->init && (init || !ctx->more)) { - err = -EINVAL; - goto unlock; + if (ctx->init && !ctx->more) { + if (ctx->used) { + err = -EINVAL; + goto unlock; + } + + pr_info_once( + "%s sent an empty control message without MSG_MORE.\n", + current->comm); } ctx->init = true;