github/falco
1
0
Fork 0
mirror of https://github.com/falcosecurity/falco.git synced 2025-09-19 08:54:47 +00:00
Code Issues Projects Releases Wiki Activity

fix(userspace/falco): timer_delete() workaround due to bug in older GLIBC

Browse Source 
Workaround for older GLIBC versions (< 2.35), where calling timer_delete()
with an invalid timer ID not returned by timer_create() causes a segfault because of
a bug in GLIBC (https://sourceware.org/bugzilla/show_bug.cgi?id=28257).

Signed-off-by: Melissa Kilby <melissa.kilby.oss@gmail.com>
This commit is contained in:
Melissa Kilby
2023-10-04 04:24:34 +00:00
committed by poiana
parent e6d71d2e8e
commit d4a4de9055
1 changed files with 24 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

28
userspace/falco/stats_writer.cpp
View File

@@ -34,6 +34,10 @@ limitations under the License.
// check that this value changed since their last observation.
static std::atomic<stats_writer::ticker_t> s_timer((stats_writer::ticker_t) 0);
static timer_t s_timerid;
// note: Workaround for older GLIBC versions (< 2.35), where calling timer_delete()
// with an invalid timer ID not returned by timer_create() causes a segfault because of
// a bug in GLIBC (https://sourceware.org/bugzilla/show_bug.cgi?id=28257).
bool s_timerid_exists = false;
static void timer_handler(int signum)
{
@@ -60,18 +64,31 @@ bool stats_writer::init_ticker(uint32_t interval_msec, std::string &err)
sev.sigev_value.sival_ptr = &s_timerid;
#ifndef __EMSCRIPTEN__
// delete any previously set timer
timer_delete(s_timerid);
if (timer_create(CLOCK_MONOTONIC, &sev, &s_timerid) == -1) {
if (s_timerid_exists)
{
if (timer_delete(s_timerid) == -1)
{
err = std::string("Could not delete previous timer: ") + strerror(errno);
return false;
}
s_timerid_exists = false;
}
if (timer_create(CLOCK_MONOTONIC, &sev, &s_timerid) == -1)
{
err = std::string("Could not create periodic timer: ") + strerror(errno);
return false;
}
s_timerid_exists = true;
#endif
timer.it_value.tv_sec = interval_msec / 1000;
timer.it_value.tv_nsec = (interval_msec % 1000) * 1000 * 1000;
timer.it_interval = timer.it_value;
#ifndef __EMSCRIPTEN__
if (timer_settime(s_timerid, 0, &timer, NULL) == -1) {
if (timer_settime(s_timerid, 0, &timer, NULL) == -1)
{
err = std::string("Could not set up periodic timer: ") + strerror(errno);
return false;
}
@@ -134,7 +151,10 @@ stats_writer::~stats_writer()
}
// delete timerID and reset timer
#ifndef __EMSCRIPTEN__
timer_delete(s_timerid);
if (s_timerid_exists)
{
timer_delete(s_timerid);
}
#endif
}
}