[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PATCH 3/4] linux-user: fix TARGET_NSIG and _NSIG uses
From: |
Laurent Vivier |
Subject: |
[PATCH 3/4] linux-user: fix TARGET_NSIG and _NSIG uses |
Date: |
Sat, 1 Feb 2020 13:27:45 +0100 |
Valid signal numbers are between 1 (SIGHUP) and SIGRTMAX.
System includes define _NSIG to SIGRTMAX + 1, but
QEMU (like kernel) defines TARGET_NSIG to TARGET_SIGRTMAX.
Fix all the checks involving the signal range.
Signed-off-by: Laurent Vivier <address@hidden>
---
linux-user/signal.c | 51 ++++++++++++++++++++++++++++++++-------------
1 file changed, 37 insertions(+), 14 deletions(-)
diff --git a/linux-user/signal.c b/linux-user/signal.c
index f42a2e1a82a5..3491f0a7ecb1 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -30,6 +30,15 @@ static struct target_sigaction sigact_table[TARGET_NSIG];
static void host_signal_handler(int host_signum, siginfo_t *info,
void *puc);
+
+/*
+ * 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
+ * Signal number 0 is reserved for use as kill(pid, 0), to test whether
+ * a process exists without sending it a signal.
+ */
+QEMU_BUILD_BUG_ON(__SIGRTMAX + 1 != _NSIG);
static uint8_t host_to_target_signal_table[_NSIG] = {
[SIGHUP] = TARGET_SIGHUP,
[SIGINT] = TARGET_SIGINT,
@@ -67,19 +76,24 @@ static uint8_t host_to_target_signal_table[_NSIG] = {
[SIGSYS] = TARGET_SIGSYS,
/* next signals stay the same */
};
-static uint8_t target_to_host_signal_table[_NSIG];
+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 < 0 || sig >= _NSIG)
+ if (sig < 1 || sig >= _NSIG) {
return sig;
+ }
return host_to_target_signal_table[sig];
}
+/* valid sig is between 1 and TARGET_NSIG */
int target_to_host_signal(int sig)
{
- if (sig < 0 || sig >= _NSIG)
+ if (sig < 1 || sig > TARGET_NSIG) {
return sig;
+ }
return target_to_host_signal_table[sig];
}
@@ -100,11 +114,15 @@ static inline int target_sigismember(const
target_sigset_t *set, int signum)
void host_to_target_sigset_internal(target_sigset_t *d,
const sigset_t *s)
{
- int i;
+ int i, j;
target_sigemptyset(d);
- for (i = 1; i <= TARGET_NSIG; i++) {
+ for (i = 1; i < _NSIG; i++) {
+ j = host_to_target_signal(i);
+ if (j < 1 || j > TARGET_NSIG) {
+ continue;
+ }
if (sigismember(s, i)) {
- target_sigaddset(d, host_to_target_signal(i));
+ target_sigaddset(d, j);
}
}
}
@@ -122,11 +140,15 @@ void host_to_target_sigset(target_sigset_t *d, const
sigset_t *s)
void target_to_host_sigset_internal(sigset_t *d,
const target_sigset_t *s)
{
- int i;
+ int i, j;
sigemptyset(d);
for (i = 1; i <= TARGET_NSIG; i++) {
+ j = target_to_host_signal(i);
+ if (j < 1 || j >= _NSIG) {
+ continue;
+ }
if (target_sigismember(s, i)) {
- sigaddset(d, target_to_host_signal(i));
+ sigaddset(d, j);
}
}
}
@@ -488,13 +510,14 @@ static void signal_table_init(void)
host_to_target_signal_table[__SIGRTMAX] = __SIGRTMIN;
/* generate signal conversion tables */
- for(i = 1; i < _NSIG; i++) {
- if (host_to_target_signal_table[i] == 0)
+ for (i = 1; i < _NSIG; i++) {
+ if (host_to_target_signal_table[i] == 0) {
host_to_target_signal_table[i] = i;
- }
- for(i = 1; i < _NSIG; i++) {
+ }
j = host_to_target_signal_table[i];
- target_to_host_signal_table[j] = i;
+ if (j <= TARGET_NSIG) {
+ target_to_host_signal_table[j] = i;
+ }
}
}
@@ -517,7 +540,7 @@ void signal_init(void)
act.sa_sigaction = host_signal_handler;
for(i = 1; i <= TARGET_NSIG; i++) {
#ifdef TARGET_GPROF
- if (i == SIGPROF) {
+ if (i == TARGET_SIGPROF) {
continue;
}
#endif
--
2.24.1
- [PATCH 0/4] linux-user: fix use of SIGRTMIN, Laurent Vivier, 2020/02/01
- [PATCH 1/4] linux-user: add missing TARGET_SIGRTMIN for hppa, Laurent Vivier, 2020/02/01
- [PATCH 3/4] linux-user: fix TARGET_NSIG and _NSIG uses,
Laurent Vivier <=
- [PATCH 4/4] linux-user: fix use of SIGRTMIN, Laurent Vivier, 2020/02/01
- [PATCH 2/4] linux-user: cleanup signal.c, Laurent Vivier, 2020/02/01
- RE: [PATCH 0/4] linux-user: fix use of SIGRTMIN, Taylor Simpson, 2020/02/03
- Re: [PATCH 0/4] linux-user: fix use of SIGRTMIN, Josh Kunz, 2020/02/03