[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] [PATCH v2 13/19] linux-user: pause() should not pause if si
From: |
Peter Maydell |
Subject: |
[Qemu-devel] [PATCH v2 13/19] linux-user: pause() should not pause if signal pending |
Date: |
Fri, 27 May 2016 15:51:55 +0100 |
From: Timothy E Baldwin <address@hidden>
Fix races between signal handling and the pause syscall by
reimplementing it using block_signals() and sigsuspend().
(Using safe_syscall(pause) would also work, except that the
pause syscall doesn't exist on all architectures.)
Signed-off-by: Timothy Edward Baldwin <address@hidden>
Message-id: address@hidden
[PMM: tweaked commit message]
Reviewed-by: Peter Maydell <address@hidden>
Signed-off-by: Peter Maydell <address@hidden>
---
linux-user/syscall.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 5a34642..3fc9c8a 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -6418,7 +6418,10 @@ abi_long do_syscall(void *cpu_env, int num, abi_long
arg1,
#endif
#ifdef TARGET_NR_pause /* not on alpha */
case TARGET_NR_pause:
- ret = get_errno(pause());
+ if (!block_signals()) {
+ sigsuspend(&((TaskState *)cpu->opaque)->signal_mask);
+ }
+ ret = -TARGET_EINTR;
break;
#endif
#ifdef TARGET_NR_utime
--
1.9.1
- [Qemu-devel] [PATCH v2 00/19] linux-user: fix various signal race conditions, Peter Maydell, 2016/05/27
- [Qemu-devel] [PATCH v2 16/19] linux-user: Restart fork() if signals pending, Peter Maydell, 2016/05/27
- [Qemu-devel] [PATCH v2 18/19] linux-user: Avoid possible misalignment in host_to_target_siginfo(), Peter Maydell, 2016/05/27
- [Qemu-devel] [PATCH v2 14/19] linux-user: Restart exit() if signal pending, Peter Maydell, 2016/05/27
- [Qemu-devel] [PATCH v2 11/19] linux-user: Queue synchronous signals separately, Peter Maydell, 2016/05/27
- [Qemu-devel] [PATCH v2 12/19] linux-user: Block signals during sigaction() handling, Peter Maydell, 2016/05/27
- [Qemu-devel] [PATCH v2 13/19] linux-user: pause() should not pause if signal pending,
Peter Maydell <=
- [Qemu-devel] [PATCH v2 03/19] linux-user: Fix stray tab-indent, Peter Maydell, 2016/05/27
- [Qemu-devel] [PATCH v2 09/19] linux-user: Remove redundant gdb_queuesig(), Peter Maydell, 2016/05/27
- [Qemu-devel] [PATCH v2 08/19] linux-user: Remove redundant default action check in queue_signal(), Peter Maydell, 2016/05/27
- [Qemu-devel] [PATCH v2 10/19] linux-user: Remove real-time signal queuing, Peter Maydell, 2016/05/27
- [Qemu-devel] [PATCH v2 06/19] linux-user: Use safe_syscall for sigsuspend syscalls, Peter Maydell, 2016/05/27
- [Qemu-devel] [PATCH v2 05/19] linux-user: Define macro for size of host kernel sigset_t, Peter Maydell, 2016/05/27
- [Qemu-devel] [PATCH v2 07/19] linux-user: Fix race between multiple signals, Peter Maydell, 2016/05/27
- [Qemu-devel] [PATCH v2 02/19] linux-user: Move handle_pending_signal() to avoid need for declaration, Peter Maydell, 2016/05/27
- [Qemu-devel] [PATCH v2 01/19] linux-user: Factor out handle_signal code from process_pending_signals(), Peter Maydell, 2016/05/27
- [Qemu-devel] [PATCH v2 04/19] linux-user: Factor out uses of do_sigprocmask() from sigreturn code, Peter Maydell, 2016/05/27