timerfd: Make timerfd_settime() time namespace aware

timerfd_settime() accepts an absolute value of the expiration time if TFD_TIMER_ABSTIME is specified. This value is in the task's time namespace and has to be converted to the host's time namespace. Co-developed-by: Dmitry Safonov <[email protected]> Signed-off-by: Andrei Vagin <[email protected]> Signed-off-by: Dmitry Safonov <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
bignaux · Jan 14, 2020 · 6cd889d · 6cd889d
1 parent 89dd8ee
commit 6cd889d
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/fs/timerfd.c b/fs/timerfd.c
@@ -26,6 +26,7 @@
 #include <linux/syscalls.h>
 #include <linux/compat.h>
 #include <linux/rcupdate.h>
+#include <linux/time_namespace.h>
 
 struct timerfd_ctx {
 	union {
@@ -196,6 +197,8 @@ static int timerfd_setup(struct timerfd_ctx *ctx, int flags,
 	}
 
 	if (texp != 0) {
+		if (flags & TFD_TIMER_ABSTIME)
+			texp = timens_ktime_to_host(clockid, texp);
 		if (isalarm(ctx)) {
 			if (flags & TFD_TIMER_ABSTIME)
 				alarm_start(&ctx->t.alarm, texp);