On 7/7/23 22:15, Richard Henderson wrote:
On 7/7/23 14:19, Helge Deller wrote:
The accept4() syscall takes two flags only: SOCK_NONBLOCK and
SOCK_CLOEXEC.
Even the real Linux kernel returns -EINVAL if any other bits
have been set.
Change the implementation of accept4() to recognize those two values
only, instead of using the fcntl_flags_tbl[] bitmask translation.
Beside this correction in behaviour, it actually fixes the accept4()
emulation for hppa, mips and alpha targets for which SOCK_NONBLOCK is
different than TARGET_SOCK_NONBLOCK.
I noticed this wrong behaviour with the testcase of the debian lwt package
which failed (by timeout while hanging in the read() syscall) in qemu but
succeeded on real hardware.
Signed-off-by: Helge Deller <del...@gmx.de>
---
linux-user/syscall.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 3f1e8e7ad9..9e9317237d 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -3440,7 +3440,18 @@ static abi_long do_accept4(int fd, abi_ulong target_addr,
abi_long ret;
int host_flags;
- host_flags = target_to_host_bitmask(flags, fcntl_flags_tbl);
+ host_flags = 0;
+#if defined(SOCK_NONBLOCK)
+ if (flags & ~(TARGET_SOCK_CLOEXEC | TARGET_SOCK_NONBLOCK)) {
+ return -TARGET_EINVAL;
+ }
+ if (flags & TARGET_SOCK_NONBLOCK) {
+ host_flags |= SOCK_NONBLOCK;
+ }
+#endif
Can we avoid the ifdef?
I don't know. There are multiple such SOCK_NONBLOCK checks in the code.
Anyway, surely the TARGET bit check should not be protected by the #ifdef.
Ok.
Helge
