diff options
Diffstat (limited to 'nscd')
| -rw-r--r-- | nscd/grpcache.c | 33 |
1 files changed, 25 insertions, 8 deletions
diff --git a/nscd/grpcache.c b/nscd/grpcache.c index d09badf..f0dad4d 100644 --- a/nscd/grpcache.c +++ b/nscd/grpcache.c @@ -177,7 +177,8 @@ cache_addgr (struct database_dyn *db, int fd, request_header *req, char *cp; const size_t key_len = strlen (key); const size_t buf_len = 3 * sizeof (grp->gr_gid) + key_len + 1; - char *buf = alloca (buf_len); + size_t alloca_used = 0; + char *buf = alloca_account (buf_len, alloca_used); ssize_t n; size_t cnt; @@ -189,7 +190,7 @@ cache_addgr (struct database_dyn *db, int fd, request_header *req, /* Determine the length of all members. */ while (grp->gr_mem[gr_mem_cnt]) ++gr_mem_cnt; - gr_mem_len = (uint32_t *) alloca (gr_mem_cnt * sizeof (uint32_t)); + gr_mem_len = alloca_account (gr_mem_cnt * sizeof (uint32_t), alloca_used); for (gr_mem_cnt = 0; grp->gr_mem[gr_mem_cnt]; ++gr_mem_cnt) { gr_mem_len[gr_mem_cnt] = strlen (grp->gr_mem[gr_mem_cnt]) + 1; @@ -204,7 +205,8 @@ cache_addgr (struct database_dyn *db, int fd, request_header *req, change. Allocate memory on the cache since it is likely discarded anyway. If it turns out to be necessary to have a new record we can still allocate real memory. */ - bool alloca_used = false; + bool dataset_temporary = false; + bool dataset_malloced = false; dataset = NULL; if (he == NULL) @@ -215,10 +217,20 @@ cache_addgr (struct database_dyn *db, int fd, request_header *req, /* We cannot permanently add the result in the moment. But we can provide the result as is. Store the data in some temporary memory. */ - dataset = (struct dataset *) alloca (total + n); + if (! __libc_use_alloca (alloca_used + total + n)) + { + dataset = malloc (total + n); + /* Perhaps we should log a message that we were unable + to allocate memory for a large request. */ + if (dataset == NULL) + goto out; + dataset_malloced = true; + } + else + dataset = alloca_account (total + n, alloca_used); /* We cannot add this record to the permanent database. */ - alloca_used = true; + dataset_temporary = true; } dataset->head.allocsize = total + n; @@ -272,6 +284,11 @@ cache_addgr (struct database_dyn *db, int fd, request_header *req, allocated on the stack and need not be freed. */ dh->timeout = dataset->head.timeout; ++dh->nreloads; + + /* If the new record was allocated via malloc, then we must free + it here. */ + if (dataset_malloced) + free (dataset); } else { @@ -287,7 +304,7 @@ cache_addgr (struct database_dyn *db, int fd, request_header *req, key_copy = (char *) newp + (key_copy - (char *) dataset); dataset = memcpy (newp, dataset, total + n); - alloca_used = false; + dataset_temporary = false; } /* Mark the old record as obsolete. */ @@ -302,7 +319,7 @@ cache_addgr (struct database_dyn *db, int fd, request_header *req, assert (fd != -1); #ifdef HAVE_SENDFILE - if (__builtin_expect (db->mmap_used, 1) && !alloca_used) + if (__builtin_expect (db->mmap_used, 1) && ! dataset_temporary) { assert (db->wr_fd != -1); assert ((char *) &dataset->resp > (char *) db->data); @@ -329,7 +346,7 @@ cache_addgr (struct database_dyn *db, int fd, request_header *req, /* Add the record to the database. But only if it has not been stored on the stack. */ - if (! alloca_used) + if (! dataset_temporary) { /* If necessary, we also propagate the data to disk. */ if (db->persistent) |