Do not return a valid signal number in one domain
when given an invalid signal number in the other domain.
Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
---
linux-user/signal.c | 72 ++++++++++++++++++++++++---------------------
1 file changed, 38 insertions(+), 34 deletions(-)
diff --git a/linux-user/signal.c b/linux-user/signal.c
index 73f40699ad..9d16e3c8c5 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -45,9 +45,8 @@ abi_ulong default_sigreturn;
abi_ulong default_rt_sigreturn;
/*
- * System includes define _NSIG as SIGRTMAX + 1,
- * but qemu (like the kernel) defines TARGET_NSIG as TARGET_SIGRTMAX
- * and the first signal is SIGHUP defined as 1
+ * System includes define _NSIG as SIGRTMAX + 1, but qemu (like the kernel)
+ * defines TARGET_NSIG as TARGET_SIGRTMAX and the first signal is 1.
* Signal number 0 is reserved for use as kill(pid, 0), to test whether
* a process exists without sending it a signal.
*/
@@ -58,7 +57,6 @@ static uint8_t host_to_target_signal_table[_NSIG] = {
#define MAKE_SIG_ENTRY(sig) [sig] = TARGET_##sig,
MAKE_SIGNAL_LIST
#undef MAKE_SIG_ENTRY
- /* next signals stay the same */
};
static uint8_t target_to_host_signal_table[TARGET_NSIG + 1];
@@ -66,18 +64,24 @@ static uint8_t target_to_host_signal_table[TARGET_NSIG + 1];
/* valid sig is between 1 and _NSIG - 1 */
int host_to_target_signal(int sig)
{
- if (sig < 1 || sig >= _NSIG) {
+ if (sig < 1) {
return sig;
}
+ if (sig >= _NSIG) {
+ return TARGET_NSIG + 1;
+ }
return host_to_target_signal_table[sig];
}
/* valid sig is between 1 and TARGET_NSIG */
int target_to_host_signal(int sig)
{
- if (sig < 1 || sig > TARGET_NSIG) {
+ if (sig < 1) {
return sig;
}
+ if (sig > TARGET_NSIG) {
+ return _NSIG;
+ }
return target_to_host_signal_table[sig];
}
@@ -508,48 +512,48 @@ static int core_dump_signal(int sig)
static void signal_table_init(void)
{
- int host_sig, target_sig, count;
+ int hsig, tsig, count;
/*
* Signals are supported starting from TARGET_SIGRTMIN and going up
- * until we run out of host realtime signals.
- * glibc at least uses only the lower 2 rt signals and probably
- * nobody's using the upper ones.
- * it's why SIGRTMIN (34) is generally greater than __SIGRTMIN (32)
- * To fix this properly we need to do manual signal delivery multiplexed
- * over a single host signal.
+ * until we run out of host realtime signals. Glibc uses the lower 2
+ * RT signals and (hopefully) nobody uses the upper ones.
+ * This is why SIGRTMIN (34) is generally greater than __SIGRTMIN (32).
+ * To fix this properly we would need to do manual signal delivery
+ * multiplexed over a single host signal.
* Attempts for configure "missing" signals via sigaction will be
* silently ignored.
*/
- for (host_sig = SIGRTMIN; host_sig <= SIGRTMAX; host_sig++) {
- target_sig = host_sig - SIGRTMIN + TARGET_SIGRTMIN;
- if (target_sig <= TARGET_NSIG) {
- host_to_target_signal_table[host_sig] = target_sig;
+ for (hsig = SIGRTMIN; hsig <= SIGRTMAX; hsig++) {
+ tsig = hsig - SIGRTMIN + TARGET_SIGRTMIN;
+ if (tsig <= TARGET_NSIG) {
+ host_to_target_signal_table[hsig] = tsig;
}
}
- /* generate signal conversion tables */
- for (target_sig = 1; target_sig <= TARGET_NSIG; target_sig++) {
- target_to_host_signal_table[target_sig] = _NSIG; /* poison */
- }
- for (host_sig = 1; host_sig < _NSIG; host_sig++) {
- if (host_to_target_signal_table[host_sig] == 0) {
- host_to_target_signal_table[host_sig] = host_sig;
- }
- target_sig = host_to_target_signal_table[host_sig];
- if (target_sig <= TARGET_NSIG) {
- target_to_host_signal_table[target_sig] = host_sig;
+ /* Invert the mapping that has already been assigned. */
+ for (hsig = 1; hsig < _NSIG; hsig++) {
+ tsig = host_to_target_signal_table[hsig];
+ if (tsig) {
+ assert(target_to_host_signal_table[tsig] == 0);
+ target_to_host_signal_table[tsig] = hsig;
}
}
- if (trace_event_get_state_backends(TRACE_SIGNAL_TABLE_INIT)) {
- for (target_sig = 1, count = 0; target_sig <= TARGET_NSIG;
target_sig++) {
- if (target_to_host_signal_table[target_sig] == _NSIG) {
- count++;
- }
+ /* Map everything else out-of-bounds. */
+ for (hsig = 1; hsig < _NSIG; hsig++) {
+ if (host_to_target_signal_table[hsig] == 0) {
+ host_to_target_signal_table[hsig] = TARGET_NSIG + 1;
}
- trace_signal_table_init(count);
}
+ for (count = 0, tsig = 1; tsig <= TARGET_NSIG; tsig++) {
+ if (target_to_host_signal_table[tsig] == 0) {
+ target_to_host_signal_table[tsig] = _NSIG;
+ count++;
+ }
+ }
+
+ trace_signal_table_init(count);
}
void signal_init(void)
--
2.34.1
