1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
|
/*
CCpp.cpp - the hook for C/C++ crashing program
Copyright (C) 2009 Zdenek Prikryl (zprikryl@redhat.com)
Copyright (C) 2009 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.
*/
#include "abrtlib.h"
#include "DebugDump.h"
#include "ABRTException.h"
#include <syslog.h>
#include <string>
#define FILENAME_EXECUTABLE "executable"
#define FILENAME_CMDLINE "cmdline"
#define FILENAME_COREDUMP "coredump"
#define VAR_RUN_PID_FILE VAR_RUN"/abrt.pid"
static char* get_executable(pid_t pid)
{
char buf[PATH_MAX + 1];
int len;
snprintf(buf, sizeof(buf), "/proc/%u/exe", (int)pid);
len = readlink(buf, buf, sizeof(buf)-1);
if (len >= 0)
{
buf[len] = '\0';
return xstrdup(buf);
}
return NULL;
}
// taken from kernel
#define COMMAND_LINE_SIZE 2048
static char* get_cmdline(pid_t pid)
{
char path[PATH_MAX];
char cmdline[COMMAND_LINE_SIZE];
snprintf(path, sizeof(path), "/proc/%u/cmdline", (int)pid);
int dst = 0;
int fd = open(path, O_RDONLY);
if (fd >= 0)
{
int len = read(fd, cmdline, sizeof(cmdline) - 1);
if (len >= 0)
{
int src = 0;
while (src < len)
{
char ch = cmdline[src++];
if (ch == '\0')
{
cmdline[dst++] = ' ';
}
/* TODO: maybe just ch >= ' '? */
else if (isspace(ch) || (isascii(ch) && !iscntrl(ch)))
{
cmdline[dst++] = ch;
}
}
}
close(fd);
}
cmdline[dst] = '\0';
return xstrdup(cmdline);
}
static int daemon_is_ok()
{
char pid[sizeof(pid_t)*3 + 2];
char path[PATH_MAX];
struct stat buff;
int fd = open(VAR_RUN_PID_FILE, O_RDONLY);
if (fd < 0)
{
return 0;
}
int len = read(fd, pid, sizeof(pid)-1);
close(fd);
if (len <= 0)
return 0;
pid[len] = '\0';
*strchrnul(pid, '\n') = '\0';
/* paranoia: we don't want to check /proc//stat or /proc///stat */
if (pid[0] == '\0' || pid[0] == '/')
return 0;
/* TODO: maybe readlink and check that it is "xxx/abrt"? */
snprintf(path, sizeof(path), "/proc/%s/stat", pid);
if (stat(path, &buff) == -1)
{
return 0;
}
return 1;
}
int main(int argc, char** argv)
{
const char* program_name = argv[0];
if (argc < 4)
{
error_msg_and_die("Usage: %s: <dddir> <pid> <signal> <uid>", program_name);
}
openlog("abrt", 0, LOG_DAEMON);
logmode = LOGMODE_SYSLOG;
const char* dddir = argv[1];
pid_t pid = atoi(argv[2]);
const char* signal_str = argv[3];
int signal = atoi(argv[3]);
uid_t uid = atoi(argv[4]);
if (signal != SIGQUIT
&& signal != SIGILL
&& signal != SIGABRT
&& signal != SIGFPE
&& signal != SIGSEGV
) {
/* not an error, exit silently */
return 0;
}
if (pid <= 0 || uid < 0)
{
error_msg_and_die("pid '%s' or uid '%s' are bogus", argv[2], argv[4]);
}
if (!daemon_is_ok())
{
/* not an error, exit with exitcode 0 */
log("abrt daemon is not running. If it crashed, "
"/proc/sys/kernel/core_pattern contains a stale value, "
"consider resetting it to 'core'"
);
return 0;
}
try
{
char* executable;
char* cmdline;
executable = get_executable(pid);
cmdline = get_cmdline(pid);
if (executable == NULL || cmdline == NULL)
{
error_msg_and_die("can not get proc info for pid %u", (int)pid);
}
if (strstr(executable, "/abrt"))
{
/* free(executable); - why bother? */
/* free(cmdline); */
error_msg_and_die("pid %u is '%s', not dumping it to avoid abrt recursion",
(int)pid, executable);
}
char path[PATH_MAX];
snprintf(path, sizeof(path), "%s/ccpp-%ld-%u", dddir, (long)time(NULL), (int)pid);
CDebugDump dd;
dd.Create(path, uid);
dd.SaveText(FILENAME_ANALYZER, "CCpp");
dd.SaveText(FILENAME_EXECUTABLE, executable);
dd.SaveText(FILENAME_CMDLINE, cmdline);
dd.SaveText(FILENAME_REASON, std::string("Process was terminated by signal ") + signal_str);
snprintf(path + strlen(path), sizeof(path), "/%s", FILENAME_COREDUMP);
int fd;
/* We need coredumps to be readable by all, because
* process producing backtraces is run under the same UID
* as the crashed process.
* Thus 644, not 600 */
fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
if (fd < 0)
{
dd.Delete();
dd.Close();
perror_msg_and_die("can't open '%s'", path);
}
if (copyfd_eof(STDIN_FILENO, fd) < 0)
{
/* close(fd); - why bother? */
dd.Delete();
dd.Close();
/* copyfd_eof logs the error including errno string,
* but it does not log file name */
error_msg_and_die("error saving coredump to %s", path);
}
/* close(fd); - why bother? */
/* free(executable); */
/* free(cmdline); */
dd.Close();
log("saved core dump of pid %u to %s", (int)pid, path);
}
catch (CABRTException& e)
{
error_msg_and_die("%s", e.what().c_str());
}
catch (std::exception& e)
{
error_msg_and_die("%s", e.what());
}
return 0;
}
|