coredump: when storing an incomplete coredump, add COREDUMP_TRUNCATED=yes

We logged about this, but did not attach information directly to the log
entry. It *would* be nice to log the full untruncated size, but afaict, to do
this, we would have to read the full data from the kernel. Doing this just to
log that information seems a bit excessive, in particular when the limit could
be set quite low. So for now let's just add a boolean field.

1 files changed, 19 insertions, 7 deletions

diff --git a/src/coredump/coredump.c b/src/coredump/coredump.c
index e38cc59a36..855f0e9330 100644
--- a/src/coredump/coredump.c
+++ b/src/coredump/coredump.c
@@ -324,7 +324,8 @@ static int save_external_coredump(
                 char **ret_filename,
                 int *ret_node_fd,
                 int *ret_data_fd,
-                uint64_t *ret_size) {
+                uint64_t *ret_size,
+                bool *truncated) {
 
         _cleanup_free_ char *fn = NULL, *tmp = NULL;
         _cleanup_close_ int fd = -1;
@@ -372,7 +373,9 @@ static int save_external_coredump(
         if (r < 0) {
                 log_error_errno(r, "Cannot store coredump of %s (%s): %m", context[CONTEXT_PID], context[CONTEXT_COMM]);
                 goto fail;
-        } else if (r == 1)
+        }
+        *truncated = r == 1;
+        if (*truncated)
                 log_struct(LOG_INFO,
                            LOG_MESSAGE("Core file was truncated to %zu bytes.", max_size),
                            "SIZE_LIMIT=%zu", max_size,
@@ -691,6 +694,8 @@ static int change_uid_gid(const char *context[]) {
         return drop_privileges(uid, gid, 0);
 }
 
+#define SUBMIT_COREDUMP_FIELDS 4
+
 static int submit_coredump(
                 const char *context[_CONTEXT_MAX],
                 struct iovec *iovec,
@@ -701,18 +706,20 @@ static int submit_coredump(
         _cleanup_close_ int coredump_fd = -1, coredump_node_fd = -1;
         _cleanup_free_ char *core_message = NULL, *filename = NULL, *coredump_data = NULL;
         uint64_t coredump_size = UINT64_MAX;
+        bool truncated = false;
         int r;
 
         assert(context);
         assert(iovec);
-        assert(n_iovec_allocated >= n_iovec + 3);
+        assert(n_iovec_allocated >= n_iovec + SUBMIT_COREDUMP_FIELDS);
         assert(input_fd >= 0);
 
         /* Vacuum before we write anything again */
         (void) coredump_vacuum(-1, arg_keep_free, arg_max_use);
 
         /* Always stream the coredump to disk, if that's possible */
-        r = save_external_coredump(context, input_fd, &filename, &coredump_node_fd, &coredump_fd, &coredump_size);
+        r = save_external_coredump(context, input_fd,
+                                   &filename, &coredump_node_fd, &coredump_fd, &coredump_size, &truncated);
         if (r < 0)
                 /* Skip whole core dumping part */
                 goto log;
@@ -770,6 +777,9 @@ log:
         if (core_message)
                 IOVEC_SET_STRING(iovec[n_iovec++], core_message);
 
+        if (truncated)
+                IOVEC_SET_STRING(iovec[n_iovec++], "COREDUMP_TRUNCATED=yes");
+
         /* Optionally store the entire coredump in the journal */
         if (arg_storage == COREDUMP_STORAGE_JOURNAL) {
                 if (coredump_size <= arg_journal_size_max) {
@@ -861,7 +871,7 @@ static int process_socket(int fd) {
                 ssize_t n;
                 ssize_t l;
 
-                if (!GREEDY_REALLOC(iovec, n_allocated, n_iovec + 3)) {
+                if (!GREEDY_REALLOC(iovec, n_allocated, n_iovec + SUBMIT_COREDUMP_FIELDS)) {
                         r = log_oom();
                         goto finish;
                 }
@@ -925,7 +935,7 @@ static int process_socket(int fd) {
                 n_iovec++;
         }
 
-        if (!GREEDY_REALLOC(iovec, n_allocated, n_iovec + 3)) {
+        if (!GREEDY_REALLOC(iovec, n_allocated, n_iovec + SUBMIT_COREDUMP_FIELDS)) {
                 r = log_oom();
                 goto finish;
         }
@@ -1027,6 +1037,7 @@ static int process_special_crash(const char *context[], int input_fd) {
         _cleanup_close_ int coredump_fd = -1, coredump_node_fd = -1;
         _cleanup_free_ char *filename = NULL;
         uint64_t coredump_size;
+        bool truncated;
         int r;
 
         assert(context);
@@ -1037,7 +1048,8 @@ static int process_special_crash(const char *context[], int input_fd) {
         if (arg_storage != COREDUMP_STORAGE_NONE)
                 arg_storage = COREDUMP_STORAGE_EXTERNAL;
 
-        r = save_external_coredump(context, input_fd, &filename, &coredump_node_fd, &coredump_fd, &coredump_size);
+        r = save_external_coredump(context, input_fd,
+                                   &filename, &coredump_node_fd, &coredump_fd, &coredump_size, &truncated);
         if (r < 0)
                 return r;