6:58 a.m.
From: BiaoXiang Ye <yebiaoxiang(a)huawei.com>
use G_USEC_PER_SEC instead of self-defining macro
v2:
- using monotonic timer instead of detecting a jump backwards
BiaoXiang Ye (1):
rpc: avoid crash when system time jump back
src/rpc/virkeepalive.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)
--
2.23.0
6:58 a.m.
New subject: [PATCH v3 1/1] 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 | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)
diff --git a/src/rpc/virkeepalive.c b/src/rpc/virkeepalive.c
index 860b91b6b1..119427eb03 100644
--- a/src/rpc/virkeepalive.c
+++ b/src/rpc/virkeepalive.c
@@ -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() / G_USEC_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() / G_USEC_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() / G_USEC_PER_SEC;
+ ka->lastPacketReceived = ka->intervalStart;
if (msg->header.prog == KEEPALIVE_PROGRAM &&
msg->header.vers == KEEPALIVE_PROTOCOL_VERSION &&
--
2.23.0
6:54 p.m.
On a Wednesday in 2021, BiaoxiangYe wrote:
From: BiaoXiang Ye <yebiaoxiang(a)huawei.com>
use G_USEC_PER_SEC instead of self-defining macro
v2:
- using monotonic timer instead of detecting a jump backwards
BiaoXiang Ye (1):
rpc: avoid crash when system time jump back
src/rpc/virkeepalive.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)
Reviewed-by: Ján Tomko <jtomko(a)redhat.com>
and pushed.
Jano
1307
days inactive
1314
days old
2 comments
2 participants
participants (2)
-
BiaoxiangYe -
Ján Tomko