[Qemu-devel] [PATCH] linux-user: pass correct host flags to accept4()

[Petar Jovanovic]

From: Petar Jovanovic <address@hidden>

Flags NONBLOCK and CLOEXEC can have different values on the host and the
guest, so set correct host values before calling accept4().

This fixes several issues with accept4 system call and user-mode of QEMU.

Signed-off-by: Petar Jovanovic <address@hidden>
---
 linux-user/syscall.c |   13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 2eac6d5..3447419 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -2062,9 +2062,18 @@ static abi_long do_accept4(int fd, abi_ulong target_addr,
     socklen_t addrlen;
     void *addr;
     abi_long ret;
+    int host_flags;
+
+    host_flags = flags & (~(TARGET_O_NONBLOCK | TARGET_O_CLOEXEC));
+    if (flags & TARGET_O_NONBLOCK) {
+        host_flags |= O_NONBLOCK;
+    }
+    if (flags & TARGET_O_CLOEXEC) {
+        host_flags |= O_CLOEXEC;
+    }
 
     if (target_addr == 0) {
-        return get_errno(accept4(fd, NULL, NULL, flags));
+        return get_errno(accept4(fd, NULL, NULL, host_flags));
     }
 
     /* linux returns EINVAL if addrlen pointer is invalid */
@@ -2080,7 +2089,7 @@ static abi_long do_accept4(int fd, abi_ulong target_addr,
 
     addr = alloca(addrlen);
 
-    ret = get_errno(accept4(fd, addr, &addrlen, flags));
+    ret = get_errno(accept4(fd, addr, &addrlen, host_flags));
     if (!is_error(ret)) {
         host_to_target_sockaddr(target_addr, addr, addrlen);
         if (put_user_u32(addrlen, target_addrlen_addr))
-- 
1.7.9.5