lkml.org 
[lkml]   [2019]   [Jul]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[patch 3/5] lib/vdso/32: Provide legacy syscall fallbacks
To address the regression which causes seccomp to deny applications the
access to clock_gettime64() and clock_getres64() syscalls because they
are not enabled in the existing filters.

That trips over the fact that 32bit VDSOs use the new clock_gettime64() and
clock_getres64() syscalls in the fallback path.

Implement a __cvdso_clock_get*time32() variants which invokes the legacy
32bit syscalls when the architecture requests it.

The conditional can go away once all architectures are converted.

Fixes: 00b26474c2f1 ("lib/vdso: Provide generic VDSO implementation")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
lib/vdso/gettimeofday.c | 46 +++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 45 insertions(+), 1 deletion(-)

--- a/lib/vdso/gettimeofday.c
+++ b/lib/vdso/gettimeofday.c
@@ -117,6 +117,8 @@ static __maybe_unused int
return 0;
}

+#ifndef VDSO_HAS_32BIT_FALLBACK
+
static __maybe_unused int
__cvdso_clock_gettime32(clockid_t clock, struct old_timespec32 *res)
{
@@ -132,10 +134,29 @@ static __maybe_unused int
res->tv_sec = ts.tv_sec;
res->tv_nsec = ts.tv_nsec;
}
-
return ret;
}

+#else
+
+static __maybe_unused int
+__cvdso_clock_gettime32(clockid_t clock, struct old_timespec32 *res)
+{
+ struct __kernel_timespec ts;
+ int ret;
+
+ ret = __cvdso_clock_gettime_common(clock, &ts);
+
+ if (likely(!ret)) {
+ res->tv_sec = ts.tv_sec;
+ res->tv_nsec = ts.tv_nsec;
+ return 0;
+ }
+ return clock_gettime32_fallback(clock, res);
+}
+
+#endif
+
static __maybe_unused int
__cvdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz)
{
@@ -225,6 +246,8 @@ int __cvdso_clock_getres(clockid_t clock
return 0;
}

+#ifndef VDSO_HAS_32BIT_FALLBACK
+
static __maybe_unused int
__cvdso_clock_getres_time32(clockid_t clock, struct old_timespec32 *res)
{
@@ -241,4 +264,25 @@ static __maybe_unused int
}
return ret;
}
+
+#else
+
+static __maybe_unused int
+__cvdso_clock_getres_time32(clockid_t clock, struct old_timespec32 *res)
+{
+ struct __kernel_timespec ts;
+ int ret;
+
+ ret = __cvdso_clock_getres_common(clock, &ts);
+
+ if (likely(!ret)) {
+ res->tv_sec = ts.tv_sec;
+ res->tv_nsec = ts.tv_nsec;
+ return 0;
+ }
+
+ return clock_getres32_fallback(clock, res);
+}
+#endif
+
#endif /* VDSO_HAS_CLOCK_GETRES */

\
 
 \ /
  Last update: 2019-07-28 15:24    [W:0.174 / U:13.460 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site