From 97b079703350ec0f6625788fb380f1fa14d0e2c4 Mon Sep 17 00:00:00 2001
From: Peter Maydell <peter.maydell@linaro.org>
Date: Fri, 15 Jul 2016 14:57:27 +0100
Subject: [PATCH] linux-user: Fix errno for sendrecvmsg with large iovec length
The sendmsg and recvmsg syscalls use a different errno to indicate
an overlarge iovec length from readv and writev. Handle this
special case in do_sendrcvmsg_locked() to avoid getting the
default errno returned by lock_iovec().
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
---
linux-user/syscall.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 71f40e3ab8..9d18326467 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -3485,6 +3485,15 @@ static abi_long do_sendrecvmsg_locked(int fd, struct target_msghdr *msgp,
count = tswapal(msgp->msg_iovlen);
target_vec = tswapal(msgp->msg_iov);
+
+ if (count > IOV_MAX) {
+ /* sendrcvmsg returns a different errno for this condition than
+ * readv/writev, so we must catch it here before lock_iovec() does.
+ */
+ ret = -TARGET_EMSGSIZE;
+ goto out2;
+ }
+
vec = lock_iovec(send ? VERIFY_READ : VERIFY_WRITE,
target_vec, count, send);
if (vec == NULL) {
--
2.30.2