Fix write-only use of a few variables

[elogind.git] / src / journal / coredump.c

diff --git a/src/journal/coredump.c b/src/journal/coredump.c
index 91528d3c816524af3e6aa379e7f5d9d1415a9600..733373b3071d16a70710aa19e9f034ae181bf729 100644 (file)
--- a/src/journal/coredump.c
+++ b/src/journal/coredump.c
@@ -32,11 +32,16 @@
 
 #include "log.h"
 #include "util.h"
 
 #include "log.h"
 #include "util.h"

+#include "macro.h"

 #include "mkdir.h"
 #include "special.h"
 #include "cgroup-util.h"
 
 #include "mkdir.h"
 #include "special.h"
 #include "cgroup-util.h"
 

-#define COREDUMP_MAX (24*1024*1024)
+/* Few programs have less than 3MiB resident */
+#define COREDUMP_MIN_START (3*1024*1024)
+/* Make sure to not make this larger than the maximum journal entry
+ * size. See ENTRY_SIZE_MAX in journald-native.c. */
+#define COREDUMP_MAX (767*1024*1024)

 
 enum {
         ARG_PID = 1,
 
 enum {
         ARG_PID = 1,


@@ -49,8 +54,7 @@ enum {
 };
 
 static int divert_coredump(void) {
 };
 
 static int divert_coredump(void) {

-        FILE *f;
-        int r;
+        _cleanup_fclose_ FILE *f = NULL;

 
         log_info("Detected coredump of the journal daemon itself, diverting coredump to /var/lib/systemd/coredump/.");
 
 
         log_info("Detected coredump of the journal daemon itself, diverting coredump to /var/lib/systemd/coredump/.");
 


@@ -70,19 +74,16 @@ static int divert_coredump(void) {
                 if (l <= 0) {
                         if (ferror(f)) {
                                 log_error("Failed to read coredump: %m");
                 if (l <= 0) {
                         if (ferror(f)) {
                                 log_error("Failed to read coredump: %m");

-                                r = -errno;
-                                goto finish;
+                                return -errno;

                         }
 
                         }
 

-                        r = 0;

                         break;
                 }
 
                 q = fwrite(buffer, 1, l, f);
                 if (q != l) {
                         log_error("Failed to write coredump: %m");
                         break;
                 }
 
                 q = fwrite(buffer, 1, l, f);
                 if (q != l) {
                         log_error("Failed to write coredump: %m");

-                        r = -errno;
-                        goto finish;
+                        return -errno;

                 }
         }
 
                 }
         }
 


@@ -90,25 +91,24 @@ static int divert_coredump(void) {
 
         if (ferror(f)) {
                 log_error("Failed to write coredump: %m");
 
         if (ferror(f)) {
                 log_error("Failed to write coredump: %m");

-                r = -errno;
+                return -errno;

         }
 
         }
 

-finish:
-        fclose(f);
-        return r;
+        return 0;

 }
 
 int main(int argc, char* argv[]) {
         int r, j = 0;
 }
 
 int main(int argc, char* argv[]) {
         int r, j = 0;

-        char *p = NULL;
+        char *t;

         ssize_t n;
         pid_t pid;
         uid_t uid;
         gid_t gid;
         struct iovec iovec[14];
         ssize_t n;
         pid_t pid;
         uid_t uid;
         gid_t gid;
         struct iovec iovec[14];

-        char *core_pid = NULL, *core_uid = NULL, *core_gid = NULL, *core_signal = NULL,
+        size_t coredump_bufsize, coredump_size;
+        _cleanup_free_ char *core_pid = NULL, *core_uid = NULL, *core_gid = NULL, *core_signal = NULL,

                 *core_timestamp = NULL, *core_comm = NULL, *core_exe = NULL, *core_unit = NULL,
                 *core_timestamp = NULL, *core_comm = NULL, *core_exe = NULL, *core_unit = NULL,

-                *core_session = NULL, *core_message = NULL, *core_cmdline = NULL, *t;
+                *core_session = NULL, *core_message = NULL, *core_cmdline = NULL, *coredump_data = NULL;

 
         prctl(PR_SET_DUMPABLE, 0);
 
 
         prctl(PR_SET_DUMPABLE, 0);
 


@@ -143,11 +143,8 @@ int main(int argc, char* argv[]) {
                 }
 
                 core_unit = strappend("COREDUMP_UNIT=", t);
                 }
 
                 core_unit = strappend("COREDUMP_UNIT=", t);

-                free(t);
-        } else if (cg_pid_get_user_unit(pid, &t) >= 0) {
+        } else if (cg_pid_get_user_unit(pid, &t) >= 0)

                 core_unit = strappend("COREDUMP_USER_UNIT=", t);
                 core_unit = strappend("COREDUMP_USER_UNIT=", t);

-                free(t);
-        }

 
         if (core_unit)
                 IOVEC_SET_STRING(iovec[j++], core_unit);
 
         if (core_unit)
                 IOVEC_SET_STRING(iovec[j++], core_unit);


@@ -240,42 +237,48 @@ int main(int argc, char* argv[]) {
                 goto finish;
         }
 
                 goto finish;
         }
 

-        p = malloc(9 + COREDUMP_MAX);
-        if (!p) {
-                r = log_oom();
-                goto finish;
+        coredump_bufsize = COREDUMP_MIN_START;
+        coredump_data = malloc(coredump_bufsize);
+        if (!coredump_data) {
+                log_warning("Failed to allocate memory for core, core will not be stored.");
+                goto finalize;

         }
 
         }
 

-        memcpy(p, "COREDUMP=", 9);
+        memcpy(coredump_data, "COREDUMP=", 9);
+        coredump_size = 9;

 
 

-        n = loop_read(STDIN_FILENO, p + 9, COREDUMP_MAX, false);
-        if (n < 0) {
-                log_error("Failed to read core dump data: %s", strerror(-n));
-                r = (int) n;
-                goto finish;
+        for (;;) {
+                n = loop_read(STDIN_FILENO, coredump_data + coredump_size,
+                              coredump_bufsize - coredump_size, false);
+                if (n < 0) {
+                        log_error("Failed to read core data: %s", strerror(-n));
+                        r = (int) n;
+                        goto finish;
+                } else if (n == 0)
+                        break;
+
+                coredump_size += n;
+
+                if (coredump_size > COREDUMP_MAX) {
+                        log_error("Core too large, core will not be stored.");
+                        goto finalize;
+                }
+
+                if (!GREEDY_REALLOC(coredump_data, coredump_bufsize, coredump_size + 1)) {
+                        log_warning("Failed to allocate memory for core, core will not be stored.");
+                        goto finalize;
+                }

         }
 
         }
 

-        iovec[j].iov_base = p;
-        iovec[j].iov_len = 9 + n;
+        iovec[j].iov_base = coredump_data;
+        iovec[j].iov_len = coredump_size;

         j++;
 
         j++;
 

+finalize:

         r = sd_journal_sendv(iovec, j);
         if (r < 0)
         r = sd_journal_sendv(iovec, j);
         if (r < 0)

-                log_error("Failed to send coredump: %s", strerror(-r));
+                log_error("Failed to log coredump: %s", strerror(-r));

 
 finish:
 
 finish:

-        free(p);
-        free(core_pid);
-        free(core_uid);
-        free(core_gid);
-        free(core_signal);
-        free(core_timestamp);
-        free(core_comm);
-        free(core_exe);
-        free(core_cmdline);
-        free(core_unit);
-        free(core_session);
-        free(core_message);
-

         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 }
         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 }