3:19 a.m.
From: BiaoXiang Ye <yebiaoxiang(a)huawei.com>
Using monotonic timer instead of detecting a jump backwards
as suggested by Jano and Daniel, thanks for suggestions.
BiaoXiang Ye (2):
rpc: avoid crash when system time jump back
rpc: introduce macro MILLISECONDS_PER_SECOND
src/rpc/virkeepalive.c | 35 +++++++++++++++++++----------------
1 file changed, 19 insertions(+), 16 deletions(-)
--
2.23.0
3:19 a.m.
New subject: [PATCH v2 1/2] rpc: avoid crash when system time jump back
From: BiaoXiang Ye <yebiaoxiang(a)huawei.com>
Setting the system time backward would lead to a
multiplication overflow in function virKeepAliveStart.
The function virKeepAliveTimerInternal got the same bug too.
Backtrace below:
#0 0x0000ffffae898470 in raise () from /usr/lib64/libc.so.6
#1 0x0000ffffae89981c in abort () from /usr/lib64/libc.so.6
#2 0x0000ffffaf9a36a8 in __mulvsi3 () from /usr/lib64/libvirt.so.0
#3 0x0000ffffaf8fd9e8 in virKeepAliveStart (ka=0xaaaaf954ce10, interval=interval
entry=0,
count=count entry=0) at ../../src/rpc/virkeepalive.c:283
#4 0x0000ffffaf908560 in virNetServerClientStartKeepAlive (client=0xaaaaf954cbe0)
at ../../src/rpc/virnetserverclient.c:1628
#5 0x0000aaaac57eb6dc in remoteDispatchConnectSupportsFeature (server=0xaaaaf95309d0,
msg=0xaaaaf9549d90, ret=0xffff8c007fc0, args=0xffff8c002e70, rerr=0xffff9ea054a0,
client=0xaaaaf954cbe0) at ../../src/remote/remote_daemon_dispatch.c:5063
#6 remoteDispatchConnectSupportsFeatureHelper (server=0xaaaaf95309d0,
client=0xaaaaf954cbe0,
msg=0xaaaaf9549d90, rerr=0xffff9ea054a0, args=0xffff8c002e70, ret=0xffff8c007fc0)
at ./remote/remote_daemon_dispatch_stubs.h:3503
#7 0x0000ffffaf9053a4 in virNetServerProgramDispatchCall(msg=0xaaaaf9549d90,
client=0xaaaaf954cbe0,
server=0x0, prog=0xaaaaf953a170) at ../../src/rpc/virnetserverprogram.c:451
#8 virNetServerProgramDispatch (prog=0xaaaaf953a170, server=0x0, server
entry=0xaaaaf95309d0,
client=0xaaaaf954cbe0, msg=0xaaaaf9549d90) at
../../src/rpc/virnetserverprogram.c:306
#9 0x0000ffffaf90a6bc in virNetServerProcessMsg (msg=<optimized out>,
prog=<optimized out>,
client=<optimized out>, srv=0xaaaaf95309d0) at
../../src/rpc/virnetserver.c:137
#10 virNetServerHandleJob (jobOpaque=0xaaaaf950df80, opaque=0xaaaaf95309d0)
at ../../src/rpc/virnetserver.c:154
#11 0x0000ffffaf812e14 in virThreadPoolWorker (opaque=<optimized out>)
at ../../src/util/virthreadpool.c:163
#12 0x0000ffffaf81237c in virThreadHelper (data=<optimized out>) at
../../src/util/virthread.c:246
#13 0x0000ffffaea327ac in ?? () from /usr/lib64/libpthread.so.0
#14 0x0000ffffae93747c in ?? () from /usr/lib64/libc.so.6
(gdb) frame 3
#3 0x0000ffffaf8fd9e8 in virKeepAliveStart (ka=0xaaaaf954ce10, interval=interval
entry=0,
count=count entry=0) at ../../src/rpc/virkeepalive.c:283
283 timeout = ka->interval - delay;
(gdb) list
278 now = time(NULL);
279 delay = now - ka->lastPacketReceived; <='delay' got a negative
value
280 if (delay > ka->interval)
281 timeout = 0;
282 else
283 timeout = ka->interval - delay;
284 ka->intervalStart = now - (ka->interval - timeout);
285 ka->timer = virEventAddTimeout(timeout * 1000, virKeepAliveTimer, <=
multiplication overflow
286 ka, virObjectFreeCallback);
287 if (ka->timer < 0)
(gdb) p now
$2 = 18288001
(gdb) p ka->lastPacketReceived
$3 = 1609430405
Signed-off-by: BiaoXiang Ye <yebiaoxiang(a)huawei.com>
---
src/rpc/virkeepalive.c | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)
diff --git a/src/rpc/virkeepalive.c b/src/rpc/virkeepalive.c
index 860b91b6b1..786f9038ef 100644
--- a/src/rpc/virkeepalive.c
+++ b/src/rpc/virkeepalive.c
@@ -31,7 +31,7 @@
#include "virprobe.h"
#define VIR_FROM_THIS VIR_FROM_RPC
-
+#define MICROSEC_PER_SEC (1000 * 1000)
VIR_LOG_INIT("rpc.keepalive");
struct _virKeepAlive {
@@ -40,8 +40,8 @@ struct _virKeepAlive {
int interval;
unsigned int count;
unsigned int countToDeath;
- time_t lastPacketReceived;
- time_t intervalStart;
+ gint64 lastPacketReceived;
+ gint64 intervalStart;
int timer;
virKeepAliveSendFunc sendCB;
@@ -113,7 +113,7 @@ static bool
virKeepAliveTimerInternal(virKeepAlivePtr ka,
virNetMessagePtr *msg)
{
- time_t now = time(NULL);
+ gint64 now = g_get_monotonic_time() / MICROSEC_PER_SEC;
int timeval;
if (ka->interval <= 0 || ka->intervalStart == 0)
@@ -231,9 +231,9 @@ virKeepAliveStart(virKeepAlivePtr ka,
unsigned int count)
{
int ret = -1;
- time_t delay;
+ gint64 delay;
int timeout;
- time_t now;
+ gint64 now;
virObjectLock(ka);
@@ -270,7 +270,7 @@ virKeepAliveStart(virKeepAlivePtr ka,
"ka=%p client=%p interval=%d count=%u",
ka, ka->client, interval, count);
- now = time(NULL);
+ now = g_get_monotonic_time() / MICROSEC_PER_SEC;
delay = now - ka->lastPacketReceived;
if (delay > ka->interval)
timeout = 0;
@@ -375,7 +375,8 @@ virKeepAliveCheckMessage(virKeepAlivePtr ka,
virObjectLock(ka);
ka->countToDeath = ka->count;
- ka->lastPacketReceived = ka->intervalStart = time(NULL);
+ ka->intervalStart = g_get_monotonic_time() / MICROSEC_PER_SEC;
+ ka->lastPacketReceived = ka->intervalStart;
if (msg->header.prog == KEEPALIVE_PROGRAM &&
msg->header.vers == KEEPALIVE_PROTOCOL_VERSION &&
--
2.23.0
4:06 p.m.
New subject: [PATCH v2 1/2] rpc: avoid crash when system time jump back
On Tue, 9 Feb 2021 09:19:47 +0000
BiaoxiangYe <yebiaoxiang(a)huawei.com> wrote:
From: BiaoXiang Ye <yebiaoxiang(a)huawei.com>
Setting the system time backward would lead to a
multiplication overflow in function virKeepAliveStart.
The function virKeepAliveTimerInternal got the same bug too.
Backtrace below:
#0 0x0000ffffae898470 in raise () from /usr/lib64/libc.so.6
#1 0x0000ffffae89981c in abort () from /usr/lib64/libc.so.6
#2 0x0000ffffaf9a36a8 in __mulvsi3 () from /usr/lib64/libvirt.so.0
#3 0x0000ffffaf8fd9e8 in virKeepAliveStart (ka=0xaaaaf954ce10,
interval=interval entry=0, count=count entry=0) at
../../src/rpc/virkeepalive.c:283 #4 0x0000ffffaf908560 in
virNetServerClientStartKeepAlive (client=0xaaaaf954cbe0) at
../../src/rpc/virnetserverclient.c:1628 #5 0x0000aaaac57eb6dc in
remoteDispatchConnectSupportsFeature (server=0xaaaaf95309d0,
msg=0xaaaaf9549d90, ret=0xffff8c007fc0, args=0xffff8c002e70,
rerr=0xffff9ea054a0, client=0xaaaaf954cbe0) at
../../src/remote/remote_daemon_dispatch.c:5063 #6
remoteDispatchConnectSupportsFeatureHelper (server=0xaaaaf95309d0,
client=0xaaaaf954cbe0, msg=0xaaaaf9549d90, rerr=0xffff9ea054a0,
args=0xffff8c002e70, ret=0xffff8c007fc0) at
./remote/remote_daemon_dispatch_stubs.h:3503 #7 0x0000ffffaf9053a4
in virNetServerProgramDispatchCall(msg=0xaaaaf9549d90,
client=0xaaaaf954cbe0, server=0x0, prog=0xaaaaf953a170) at
../../src/rpc/virnetserverprogram.c:451 #8
virNetServerProgramDispatch (prog=0xaaaaf953a170, server=0x0, server
entry=0xaaaaf95309d0, client=0xaaaaf954cbe0, msg=0xaaaaf9549d90) at
../../src/rpc/virnetserverprogram.c:306 #9 0x0000ffffaf90a6bc in
virNetServerProcessMsg (msg=<optimized out>, prog=<optimized out>,
client=<optimized out>, srv=0xaaaaf95309d0) at
../../src/rpc/virnetserver.c:137 #10 virNetServerHandleJob
(jobOpaque=0xaaaaf950df80, opaque=0xaaaaf95309d0) at
../../src/rpc/virnetserver.c:154 #11 0x0000ffffaf812e14 in
virThreadPoolWorker (opaque=<optimized out>) at
../../src/util/virthreadpool.c:163 #12 0x0000ffffaf81237c in
virThreadHelper (data=<optimized out>) at
../../src/util/virthread.c:246 #13 0x0000ffffaea327ac in ?? () from
/usr/lib64/libpthread.so.0 #14 0x0000ffffae93747c in ?? () from
/usr/lib64/libc.so.6 (gdb) frame 3 #3 0x0000ffffaf8fd9e8 in
virKeepAliveStart (ka=0xaaaaf954ce10, interval=interval entry=0,
count=count entry=0) at ../../src/rpc/virkeepalive.c:283 283
timeout = ka->interval - delay; (gdb) list 278 now = time(NULL);
279 delay = now - ka->lastPacketReceived; <='delay' got a negative
value 280 if (delay > ka->interval) 281 timeout = 0; 282
else 283 timeout = ka->interval - delay; 284
ka->intervalStart = now - (ka->interval - timeout); 285 ka->timer
= virEventAddTimeout(timeout * 1000, virKeepAliveTimer, <=
multiplication overflow 286 ka,
virObjectFreeCallback); 287 if (ka->timer < 0) (gdb) p now $2 =
18288001 (gdb) p ka->lastPacketReceived
$3 = 1609430405
Signed-off-by: BiaoXiang Ye <yebiaoxiang(a)huawei.com>
---
src/rpc/virkeepalive.c | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)
diff --git a/src/rpc/virkeepalive.c b/src/rpc/virkeepalive.c
index 860b91b6b1..786f9038ef 100644
--- a/src/rpc/virkeepalive.c
+++ b/src/rpc/virkeepalive.c
@@ -31,7 +31,7 @@
#include "virprobe.h"
#define VIR_FROM_THIS VIR_FROM_RPC
-
+#define MICROSEC_PER_SEC (1000 * 1000)
FYI, glib provides G_USEC_PER_SEC which you could use here instead of
defining your own.
Reviewed-by: Jonathon Jongsma <jjongsma(a)redhat.com>
VIR_LOG_INIT("rpc.keepalive");
struct _virKeepAlive {
@@ -40,8 +40,8 @@ struct _virKeepAlive {
int interval;
unsigned int count;
unsigned int countToDeath;
- time_t lastPacketReceived;
- time_t intervalStart;
+ gint64 lastPacketReceived;
+ gint64 intervalStart;
int timer;
virKeepAliveSendFunc sendCB;
@@ -113,7 +113,7 @@ static bool
virKeepAliveTimerInternal(virKeepAlivePtr ka,
virNetMessagePtr *msg)
{
- time_t now = time(NULL);
+ gint64 now = g_get_monotonic_time() / MICROSEC_PER_SEC;
int timeval;
if (ka->interval <= 0 || ka->intervalStart == 0)
@@ -231,9 +231,9 @@ virKeepAliveStart(virKeepAlivePtr ka,
unsigned int count)
{
int ret = -1;
- time_t delay;
+ gint64 delay;
int timeout;
- time_t now;
+ gint64 now;
virObjectLock(ka);
@@ -270,7 +270,7 @@ virKeepAliveStart(virKeepAlivePtr ka,
"ka=%p client=%p interval=%d count=%u",
ka, ka->client, interval, count);
- now = time(NULL);
+ now = g_get_monotonic_time() / MICROSEC_PER_SEC;
delay = now - ka->lastPacketReceived;
if (delay > ka->interval)
timeout = 0;
@@ -375,7 +375,8 @@ virKeepAliveCheckMessage(virKeepAlivePtr ka,
virObjectLock(ka);
ka->countToDeath = ka->count;
- ka->lastPacketReceived = ka->intervalStart = time(NULL);
+ ka->intervalStart = g_get_monotonic_time() / MICROSEC_PER_SEC;
+ ka->lastPacketReceived = ka->intervalStart;
if (msg->header.prog == KEEPALIVE_PROGRAM &&
msg->header.vers == KEEPALIVE_PROTOCOL_VERSION &&
3:19 a.m.
New subject: [PATCH v2 2/2] rpc: introduce macro MILLISECONDS_PER_SECOND
From: BiaoXiang Ye <yebiaoxiang(a)huawei.com>
Use macro instead of magic number, keep the style consistent
with MICROSEC_PER_SEC.
Signed-off-by: BiaoXiang Ye <yebiaoxiang(a)huawei.com>
---
src/rpc/virkeepalive.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/src/rpc/virkeepalive.c b/src/rpc/virkeepalive.c
index 786f9038ef..baea2e6478 100644
--- a/src/rpc/virkeepalive.c
+++ b/src/rpc/virkeepalive.c
@@ -32,6 +32,7 @@
#define VIR_FROM_THIS VIR_FROM_RPC
#define MICROSEC_PER_SEC (1000 * 1000)
+#define MILLISECONDS_PER_SECOND (1000)
VIR_LOG_INIT("rpc.keepalive");
struct _virKeepAlive {
@@ -121,7 +122,7 @@ virKeepAliveTimerInternal(virKeepAlivePtr ka,
if (now - ka->intervalStart < ka->interval) {
timeval = ka->interval - (now - ka->intervalStart);
- virEventUpdateTimeout(ka->timer, timeval * 1000);
+ virEventUpdateTimeout(ka->timer, timeval * MILLISECONDS_PER_SECOND);
return false;
}
@@ -141,7 +142,7 @@ virKeepAliveTimerInternal(virKeepAlivePtr ka,
ka->countToDeath--;
ka->intervalStart = now;
*msg = virKeepAliveMessage(ka, KEEPALIVE_PROC_PING);
- virEventUpdateTimeout(ka->timer, ka->interval * 1000);
+ virEventUpdateTimeout(ka->timer, ka->interval * MILLISECONDS_PER_SECOND);
return false;
}
}
@@ -250,7 +251,7 @@ virKeepAliveStart(virKeepAlivePtr ka,
goto cleanup;
}
/* Guard against overflow */
- if (interval > INT_MAX / 1000) {
+ if (interval > INT_MAX / MILLISECONDS_PER_SECOND) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("keepalive interval %d too large"), interval);
goto cleanup;
@@ -277,7 +278,8 @@ virKeepAliveStart(virKeepAlivePtr ka,
else
timeout = ka->interval - delay;
ka->intervalStart = now - (ka->interval - timeout);
- ka->timer = virEventAddTimeout(timeout * 1000, virKeepAliveTimer,
+ ka->timer = virEventAddTimeout(timeout * MILLISECONDS_PER_SECOND,
+ virKeepAliveTimer,
ka, virObjectFreeCallback);
if (ka->timer < 0)
goto cleanup;
@@ -327,8 +329,8 @@ virKeepAliveTimeout(virKeepAlivePtr ka)
if (timeout < 0)
timeout = 0;
/* Guard against overflow */
- if (timeout > INT_MAX / 1000)
- timeout = INT_MAX / 1000;
+ if (timeout > INT_MAX / MILLISECONDS_PER_SECOND)
+ timeout = INT_MAX / MILLISECONDS_PER_SECOND;
}
virObjectUnlock(ka);
@@ -336,7 +338,7 @@ virKeepAliveTimeout(virKeepAlivePtr ka)
if (timeout < 0)
return -1;
else
- return timeout * 1000;
+ return timeout * MILLISECONDS_PER_SECOND;
}
@@ -403,7 +405,7 @@ virKeepAliveCheckMessage(virKeepAlivePtr ka,
}
if (ka->timer >= 0)
- virEventUpdateTimeout(ka->timer, ka->interval * 1000);
+ virEventUpdateTimeout(ka->timer, ka->interval * MILLISECONDS_PER_SECOND);
virObjectUnlock(ka);
--
2.23.0
7:54 a.m.
New subject: [PATCH v2 2/2] rpc: introduce macro MILLISECONDS_PER_SECOND
On Tue, Feb 09, 2021 at 09:19:48 +0000, BiaoxiangYe wrote:
From: BiaoXiang Ye <yebiaoxiang(a)huawei.com>
Use macro instead of magic number, keep the style consistent
with MICROSEC_PER_SEC.
I'm not sure where's the magic in converting seconds to milliseconds or
microseconds to seconds. However, I can see it's a bit easier to spot
we're converting seconds and milliseconds rather than milliseconds and
microseconds, for example.
Signed-off-by: BiaoXiang Ye <yebiaoxiang(a)huawei.com>
---
src/rpc/virkeepalive.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/src/rpc/virkeepalive.c b/src/rpc/virkeepalive.c
index 786f9038ef..baea2e6478 100644
--- a/src/rpc/virkeepalive.c
+++ b/src/rpc/virkeepalive.c
@@ -32,6 +32,7 @@
#define VIR_FROM_THIS VIR_FROM_RPC
#define MICROSEC_PER_SEC (1000 * 1000)
+#define MILLISECONDS_PER_SECOND (1000)
VIR_LOG_INIT("rpc.keepalive");
Please, keep the empty line above VIR_LOG_INIT.
MICROSEC_PER_SEC vs MILLISECONDS_PER_SECOND definitely don't use
consistent style. Ideally you could use G_USEC_PER_SEC as Jonathon
suggested, but I'm afraid there's no corresponding G_MSEC_PER_SEC to be
used in this patch. I guess G_USEC_PER_SEC and VIR_MSEC_PER_SEC could
be usable as a workaround... Or just use numbers instead of both macros,
they are quite clear anyway.
Jirka
1373
days inactive
1374
days old
4 comments
3 participants
participants (3)
-
BiaoxiangYe -
Jiri Denemark -
Jonathon Jongsma