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/*
Copyright (C) 2010 ABRT team
Copyright (C) 2010 RedHat Inc
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
Authors:
Anton Arapov <anton@redhat.com>
Arjan van de Ven <arjan@linux.intel.com>
*/
#include <syslog.h>
#include <asm/unistd.h> /* __NR_syslog */
#include <glib.h>
#include "abrtlib.h"
#include "abrt_exception.h"
#include "comm_layer_inner.h"
#include "KerneloopsSysLog.h"
#include "KerneloopsScanner.h"
// TODO: https://fedorahosted.org/abrt/ticket/78
static int scan_dmesg(GList **oopsList)
{
VERB1 log("Scanning dmesg");
/* syslog(3) - read the last len bytes from the log buffer
* (non-destructively), but dont read more than was written
* into the buffer since the last"clear ring buffer" cmd.
* Returns the number of bytes read.
*/
char *buffer = (char*)xzalloc(16*1024);
syscall(__NR_syslog, 3, buffer, 16*1024 - 1); /* always NUL terminated */
int cnt_FoundOopses = extract_oopses(oopsList, buffer, strlen(buffer));
free(buffer);
return cnt_FoundOopses;
}
/* "dumpoops" tool uses these two functions too */
extern "C" {
int scan_syslog_file(GList **oopsList, const char *filename, time_t *last_changed_p)
{
VERB1 log("Scanning syslog file '%s'", filename);
char *buffer;
struct stat statb;
int fd;
int cnt_FoundOopses;
ssize_t sz;
fd = open(filename, O_RDONLY);
if (fd < 0)
return 0;
statb.st_size = 0; /* paranoia */
if (fstat(fd, &statb) != 0 || statb.st_size < 1)
{
close(fd);
return 0;
}
if (last_changed_p != NULL)
{
if (*last_changed_p == statb.st_mtime)
{
VERB1 log("Syslog file '%s' hasn't changed since last scan, skipping", filename);
close(fd);
return 0;
}
*last_changed_p = statb.st_mtime;
}
/*
* In theory we have a race here, since someone could spew
* to /var/log/messages before we read it in... we try to
* deal with it by reading at most 10kbytes extra. If there's
* more than that.. any oops will be in dmesg anyway.
* Do not try to allocate an absurd amount of memory; ignore
* older log messages because they are unlikely to have
* sufficiently recent data to be useful. 32MB is more
* than enough; it's not worth looping through more log
* if the log is larger than that.
*/
sz = statb.st_size + 10*1024;
if (statb.st_size > (32*1024*1024 - 10*1024))
{
xlseek(fd, statb.st_size - (32*1024*1024 - 10*1024), SEEK_SET);
sz = 32*1024*1024;
}
buffer = (char*)xzalloc(sz);
sz = full_read(fd, buffer, sz);
close(fd);
cnt_FoundOopses = 0;
if (sz > 0)
cnt_FoundOopses = extract_oopses(oopsList, buffer, sz);
free(buffer);
return cnt_FoundOopses;
}
/* returns number of errors */
int save_oops_to_debug_dump(GList **oopsList)
{
unsigned countdown = 16; /* do not report hundreds of oopses */
unsigned idx = g_list_length(*oopsList);
time_t t = time(NULL);
pid_t my_pid = getpid();
VERB1 log("Saving %u oopses as crash dump dirs", idx >= countdown ? countdown-1 : idx);
char tainted[2] = {'x', '\0'};
/* once tainted flag is set to 1, only restart can reset the flag to 0 */
int tainted_fd = open("/proc/sys/kernel/tainted", O_RDONLY);
if (tainted_fd >= 0)
{
/* contain only 0 or 1 */
if (read(tainted_fd, &tainted, 1) != 1)
error_msg("Unable to read one byte from /proc/sys/kernel/tainted");
close(tainted_fd);
}
else
error_msg("/proc/sys/kernel/tainted does not exist");
int errors = 0;
while (idx != 0 && --countdown != 0)
{
char path[sizeof(DEBUG_DUMPS_DIR"/kerneloops-%lu-%lu-%lu") + 3 * sizeof(long)*3];
sprintf(path, DEBUG_DUMPS_DIR"/kerneloops-%lu-%lu-%lu", (long)t, (long)my_pid, (long)idx);
char *first_line = (char*)g_list_nth_data(*oopsList,--idx);
char *second_line = (char*)strchr(first_line, '\n'); /* never NULL */
*second_line++ = '\0';
struct dump_dir *dd = dd_create(path, /*uid:*/ 0);
if (dd)
{
dd_save_text(dd, FILENAME_ANALYZER, "Kerneloops");
dd_save_text(dd, FILENAME_EXECUTABLE, "kernel");
dd_save_text(dd, FILENAME_KERNEL, first_line);
dd_save_text(dd, FILENAME_CMDLINE, "not_applicable");
dd_save_text(dd, FILENAME_BACKTRACE, second_line);
/* Optional, makes generated bz more informative */
strchrnul(second_line, '\n')[0] = '\0';
dd_save_text(dd, FILENAME_REASON, second_line);
if (tainted[0] == '1')
dd_save_text(dd, FILENAME_TAINTED, tainted);
dd_close(dd);
}
else
errors++;
}
return errors;
}
} /* extern "C" */
CKerneloopsScanner::CKerneloopsScanner()
{
int cnt_FoundOopses;
m_syslog_last_change = 0;
/* Scan dmesg, on first call only */
GList *oopsList = NULL;
cnt_FoundOopses = scan_dmesg(&oopsList);
if (cnt_FoundOopses > 0)
{
int errors = save_oops_to_debug_dump(&oopsList);
if (errors > 0)
log("%d errors while dumping oopses", errors);
}
}
void CKerneloopsScanner::Run(const char *pActionDir, const char *pArgs, int force)
{
const char *syslog_file = "/var/log/messages";
map_plugin_settings_t::const_iterator it = m_pSettings.find("SysLogFile");
if (it != m_pSettings.end())
syslog_file = it->second.c_str();
GList *oopsList = NULL;
int cnt_FoundOopses = scan_syslog_file(&oopsList, syslog_file, &m_syslog_last_change);
if (cnt_FoundOopses > 0)
{
int errors = save_oops_to_debug_dump(&oopsList);
if (errors > 0)
log("%d errors while dumping oopses", errors);
/*
* This marker in syslog file prevents us from
* re-parsing old oopses (any oops before it is
* ignored by scan_syslog_file()). The only problem
* is that we can't be sure here that syslog_file
* is the file where syslog(xxx) stuff ends up.
*/
openlog("abrt", 0, LOG_KERN);
syslog(LOG_WARNING,
"Kerneloops: Reported %u kernel oopses to Abrt",
cnt_FoundOopses);
closelog();
}
for (GList *li = oopsList; li != NULL; li = g_list_next(li))
free((char*)li->data);
g_list_free(oopsList);
}
PLUGIN_INFO(ACTION,
CKerneloopsScanner,
"KerneloopsScanner",
"0.0.1",
_("Periodically scans for and saves kernel oopses"),
"anton@redhat.com",
"http://people.redhat.com/aarapov",
"");
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