Fix sigset printing via print_sigset().
Replace print_sigset() with print_sigset_addr_len(),
which takes not only addr, but also len parameter.
This allows us to drop "do we need to print RT signals?" parameter,
and this fixes RT signals printing in many syscalls.
sys_epoll_pwait: print RT signals too, print sigmask size argument.
sys_sigprocmask: print_sigset -> print_sigset_addr_len(current_wordsize),
no change in functionality.
sys_sigpending: use print_sigset_addr_len(current_wordsize)
instead of open-coding it.
sys_rt_sigprocmask: use print_sigset_addr_len instead of open-coding it.
sys_rt_sigpending: ditto.
sys_rt_sigsuspend: ditto.
sys_rt_sigtimedwait: ditto.
do_signalfd: print_sigset -> print_sigset_addr_len. This fixes
RT signals printing (wasn't showing them before).
sys_ppoll: ditto.
copy_sigset_len() is folded into its only user, print_sigset_addr_len(),
and copy_sigset() is gone.
While at it, checked kernel sources and noted where kernel enforces
sigset_size == NSIG / 8 (== sizeof(kernel_sigset_t)),
and where it allows word-sized sigset_size ([rt_]sigpending).
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
diff --git a/signal.c b/signal.c
index 66ce613..d863e50 100644
--- a/signal.c
+++ b/signal.c
@@ -220,20 +220,6 @@
*(long *)s = l;
}
-static int
-copy_sigset_len(struct tcb *tcp, long addr, sigset_t *s, int len)
-{
- if (len > sizeof(*s))
- len = sizeof(*s);
- sigemptyset(s);
- if (umoven(tcp, addr, len, (char *)s) < 0)
- return -1;
- return 0;
-}
-
-/* Original sigset is unsigned long */
-#define copy_sigset(tcp, addr, s) copy_sigset_len(tcp, addr, s, sizeof(long))
-
static const char *
sprintsigmask(const char *str, sigset_t *mask, int rt)
/* set might include realtime sigs */
@@ -313,16 +299,28 @@
}
void
-print_sigset(struct tcb *tcp, long addr, int rt)
+print_sigset_addr_len(struct tcb *tcp, long addr, long len)
{
sigset_t ss;
- if (!addr)
+ if (!addr) {
tprints("NULL");
- else if (copy_sigset(tcp, addr, &ss) < 0)
+ return;
+ }
+ /* Here len is usually equals NSIG / 8 or current_wordsize.
+ * But we code this defensively:
+ */
+ if (len < 0) {
+ bad:
tprintf("%#lx", addr);
- else
- printsigmask(&ss, rt);
+ return;
+ }
+ if (len > NSIG / 8)
+ len = NSIG / 8;
+ sigemptyset(&ss);
+ if (umoven(tcp, addr, len, (char *)&ss) < 0)
+ goto bad;
+ printsigmask(&ss, /*rt:*/ 1);
}
#ifndef ILL_ILLOPC
@@ -1124,10 +1122,11 @@
#ifdef HAVE_SIGACTION
+/* "Old" sigprocmask, which operates with word-sized signal masks */
int
sys_sigprocmask(struct tcb *tcp)
{
-#ifdef ALPHA
+# ifdef ALPHA
sigset_t ss;
if (entering(tcp)) {
/*
@@ -1151,22 +1150,20 @@
tcp->auxstr = sprintsigmask("old mask ", &ss, 0);
return RVAL_HEX | RVAL_STR;
}
-#else /* !ALPHA */
+# else /* !ALPHA */
if (entering(tcp)) {
printxval(sigprocmaskcmds, tcp->u_arg[0], "SIG_???");
tprints(", ");
- print_sigset(tcp, tcp->u_arg[1], 0);
+ print_sigset_addr_len(tcp, tcp->u_arg[1], current_wordsize);
tprints(", ");
}
else {
- if (!tcp->u_arg[2])
- tprints("NULL");
- else if (syserror(tcp))
+ if (syserror(tcp))
tprintf("%#lx", tcp->u_arg[2]);
else
- print_sigset(tcp, tcp->u_arg[2], 0);
+ print_sigset_addr_len(tcp, tcp->u_arg[2], current_wordsize);
}
-#endif /* !ALPHA */
+# endif /* !ALPHA */
return 0;
}
@@ -1200,15 +1197,11 @@
int
sys_sigpending(struct tcb *tcp)
{
- sigset_t sigset;
-
if (exiting(tcp)) {
if (syserror(tcp))
tprintf("%#lx", tcp->u_arg[0]);
- else if (copy_sigset(tcp, tcp->u_arg[0], &sigset) < 0)
- tprints("[?]");
else
- printsigmask(&sigset, 0);
+ print_sigset_addr_len(tcp, tcp->u_arg[0], current_wordsize);
}
return 0;
}
@@ -1216,30 +1209,18 @@
int
sys_rt_sigprocmask(struct tcb *tcp)
{
- sigset_t sigset;
-
- /* Note: arg[3] is the length of the sigset. */
+ /* Note: arg[3] is the length of the sigset. Kernel requires NSIG / 8 */
if (entering(tcp)) {
printxval(sigprocmaskcmds, tcp->u_arg[0], "SIG_???");
tprints(", ");
- if (!tcp->u_arg[1])
- tprints("NULL, ");
- else if (copy_sigset_len(tcp, tcp->u_arg[1], &sigset, tcp->u_arg[3]) < 0)
- tprintf("%#lx, ", tcp->u_arg[1]);
- else {
- printsigmask(&sigset, 1);
- tprints(", ");
- }
+ print_sigset_addr_len(tcp, tcp->u_arg[1], tcp->u_arg[3]);
+ tprints(", ");
}
else {
- if (!tcp->u_arg[2])
- tprints("NULL");
- else if (syserror(tcp))
+ if (syserror(tcp))
tprintf("%#lx", tcp->u_arg[2]);
- else if (copy_sigset_len(tcp, tcp->u_arg[2], &sigset, tcp->u_arg[3]) < 0)
- tprints("[?]");
else
- printsigmask(&sigset, 1);
+ print_sigset_addr_len(tcp, tcp->u_arg[2], tcp->u_arg[3]);
tprintf(", %lu", tcp->u_arg[3]);
}
return 0;
@@ -1367,16 +1348,18 @@
int
sys_rt_sigpending(struct tcb *tcp)
{
- sigset_t sigset;
-
if (exiting(tcp)) {
+ /*
+ * One of the few syscalls where sigset size (arg[1])
+ * is allowed to be <= NSIG / 8, not strictly ==.
+ * This allows non-rt sigpending() syscall
+ * to reuse rt_sigpending() code in kernel.
+ */
if (syserror(tcp))
tprintf("%#lx", tcp->u_arg[0]);
- else if (copy_sigset_len(tcp, tcp->u_arg[0],
- &sigset, tcp->u_arg[1]) < 0)
- tprints("[?]");
else
- printsigmask(&sigset, 1);
+ print_sigset_addr_len(tcp, tcp->u_arg[0], tcp->u_arg[1]);
+ tprintf(", %lu", tcp->u_arg[1]);
}
return 0;
}
@@ -1385,11 +1368,9 @@
sys_rt_sigsuspend(struct tcb *tcp)
{
if (entering(tcp)) {
- sigset_t sigm;
- if (copy_sigset_len(tcp, tcp->u_arg[0], &sigm, tcp->u_arg[1]) < 0)
- tprints("[?]");
- else
- printsigmask(&sigm, 1);
+ /* NB: kernel requires arg[1] == NSIG / 8 */
+ print_sigset_addr_len(tcp, tcp->u_arg[0], tcp->u_arg[1]);
+ tprintf(", %lu", tcp->u_arg[1]);
}
return 0;
}
@@ -1424,14 +1405,9 @@
int sys_rt_sigtimedwait(struct tcb *tcp)
{
+ /* NB: kernel requires arg[3] == NSIG / 8 */
if (entering(tcp)) {
- sigset_t sigset;
-
- if (copy_sigset_len(tcp, tcp->u_arg[0],
- &sigset, tcp->u_arg[3]) < 0)
- tprints("[?]");
- else
- printsigmask(&sigset, 1);
+ print_sigset_addr_len(tcp, tcp->u_arg[0], tcp->u_arg[3]);
tprints(", ");
/* This is the only "return" parameter, */
if (tcp->u_arg[1] != 0)
@@ -1449,7 +1425,7 @@
return 0;
}
print_timespec(tcp, tcp->u_arg[2]);
- tprintf(", %d", (int) tcp->u_arg[3]);
+ tprintf(", %lu", tcp->u_arg[3]);
return 0;
};
@@ -1464,10 +1440,11 @@
static int
do_signalfd(struct tcb *tcp, int flags_arg)
{
+ /* NB: kernel requires arg[2] == NSIG / 8 */
if (entering(tcp)) {
printfd(tcp, tcp->u_arg[0]);
tprints(", ");
- print_sigset(tcp, tcp->u_arg[1], 1);
+ print_sigset_addr_len(tcp, tcp->u_arg[1], tcp->u_arg[2]);
tprintf(", %lu", tcp->u_arg[2]);
if (flags_arg >= 0) {
tprints(", ");