linux-kernel - [PATCH] timer_list: Use printk format instead of open-coded symbol lookup

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 4 Nov 2020 17:34:01 +0100
From:   Helge Deller <deller@....de>
To:     Thomas Gleixner <tglx@...utronix.de>,
        John Stultz <john.stultz@...aro.org>,
        Stephen Boyd <sboyd@...nel.org>, linux-kernel@...r.kernel.org
Cc:     linux-parisc@...r.kernel.org
Subject: [PATCH] timer_list: Use printk format instead of open-coded symbol
 lookup

Use the "%ps" printk format string to resolve symbol names.

This works on all platforms, including ia64, ppc64 and parisc64 on which
one needs to dereference pointers to function descriptors instead of
function pointers.

Signed-off-by: Helge Deller <deller@....de>

diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c
index acb326f5f50a..6939140ab7c5 100644
--- a/kernel/time/timer_list.c
+++ b/kernel/time/timer_list.c
@@ -42,24 +42,11 @@ static void SEQ_printf(struct seq_file *m, const char *fmt, ...)
 	va_end(args);
 }

-static void print_name_offset(struct seq_file *m, void *sym)
-{
-	char symname[KSYM_NAME_LEN];
-
-	if (lookup_symbol_name((unsigned long)sym, symname) < 0)
-		SEQ_printf(m, "<%pK>", sym);
-	else
-		SEQ_printf(m, "%s", symname);
-}
-
 static void
 print_timer(struct seq_file *m, struct hrtimer *taddr, struct hrtimer *timer,
 	    int idx, u64 now)
 {
-	SEQ_printf(m, " #%d: ", idx);
-	print_name_offset(m, taddr);
-	SEQ_printf(m, ", ");
-	print_name_offset(m, timer->function);
+	SEQ_printf(m, " #%d: <%pK>, %ps", idx, taddr, timer->function);
 	SEQ_printf(m, ", S:%02x", timer->state);
 	SEQ_printf(m, "\n");
 	SEQ_printf(m, " # expires at %Lu-%Lu nsecs [in %Ld to %Ld nsecs]\n",
@@ -116,9 +103,7 @@ print_base(struct seq_file *m, struct hrtimer_clock_base *base, u64 now)

 	SEQ_printf(m, "  .resolution: %u nsecs\n", hrtimer_resolution);

-	SEQ_printf(m,   "  .get_time:   ");
-	print_name_offset(m, base->get_time);
-	SEQ_printf(m,   "\n");
+	SEQ_printf(m,   "  .get_time:   %ps\n", base->get_time);
 #ifdef CONFIG_HIGH_RES_TIMERS
 	SEQ_printf(m, "  .offset:     %Lu nsecs\n",
 		   (unsigned long long) ktime_to_ns(base->offset));
@@ -218,42 +203,29 @@ print_tickdevice(struct seq_file *m, struct tick_device *td, int cpu)
 	SEQ_printf(m, " next_event:     %Ld nsecs\n",
 		   (unsigned long long) ktime_to_ns(dev->next_event));

-	SEQ_printf(m, " set_next_event: ");
-	print_name_offset(m, dev->set_next_event);
-	SEQ_printf(m, "\n");
+	SEQ_printf(m, " set_next_event: %ps\n", dev->set_next_event);

-	if (dev->set_state_shutdown) {
-		SEQ_printf(m, " shutdown: ");
-		print_name_offset(m, dev->set_state_shutdown);
-		SEQ_printf(m, "\n");
-	}
+	if (dev->set_state_shutdown)
+		SEQ_printf(m, " shutdown:       %ps\n",
+			dev->set_state_shutdown);

-	if (dev->set_state_periodic) {
-		SEQ_printf(m, " periodic: ");
-		print_name_offset(m, dev->set_state_periodic);
-		SEQ_printf(m, "\n");
-	}
+	if (dev->set_state_periodic)
+		SEQ_printf(m, " periodic:       %ps\n",
+			dev->set_state_periodic);

-	if (dev->set_state_oneshot) {
-		SEQ_printf(m, " oneshot:  ");
-		print_name_offset(m, dev->set_state_oneshot);
-		SEQ_printf(m, "\n");
-	}
+	if (dev->set_state_oneshot)
+		SEQ_printf(m, " oneshot:        %ps\n",
+			dev->set_state_oneshot);

-	if (dev->set_state_oneshot_stopped) {
-		SEQ_printf(m, " oneshot stopped: ");
-		print_name_offset(m, dev->set_state_oneshot_stopped);
-		SEQ_printf(m, "\n");
-	}
+	if (dev->set_state_oneshot_stopped)
+		SEQ_printf(m, " oneshot stopped: %ps\n",
+			dev->set_state_oneshot_stopped);

-	if (dev->tick_resume) {
-		SEQ_printf(m, " resume:   ");
-		print_name_offset(m, dev->tick_resume);
-		SEQ_printf(m, "\n");
-	}
+	if (dev->tick_resume)
+		SEQ_printf(m, " resume:         %ps\n",
+			dev->tick_resume);

-	SEQ_printf(m, " event_handler:  ");
-	print_name_offset(m, dev->event_handler);
+	SEQ_printf(m, " event_handler:  %ps\n", dev->event_handler);
 	SEQ_printf(m, "\n");
 	SEQ_printf(m, " retries:        %lu\n", dev->retries);
 	SEQ_printf(m, "\n");