diff options
| -rw-r--r-- | ChangeLog | 6 | ||||
| -rw-r--r-- | nscd/nscd_helper.c | 59 |
2 files changed, 35 insertions, 30 deletions
@@ -1,3 +1,9 @@ +2007-08-28 Ulrich Drepper <drepper@redhat.com> + + * nscd/nscd_helper.c (get_mapping): Avoid the pread call, just go + ahead and map the file. This should always be correct and we can + catch problems later. + 2007-08-28 Jakub Jelinek <jakub@redhat.com> * libio/bits/stdio2.h (__fread_chk, __fread_unlocked_chk): New diff --git a/nscd/nscd_helper.c b/nscd/nscd_helper.c index 50146a0..780878d 100644 --- a/nscd/nscd_helper.c +++ b/nscd/nscd_helper.c @@ -286,45 +286,44 @@ get_mapping (request_type type, const char *key, || __builtin_expect (st.st_size < sizeof (struct database_pers_head), 0)) goto out_close; - struct database_pers_head head; - if (__builtin_expect (TEMP_FAILURE_RETRY (__pread (mapfd, &head, - sizeof (head), 0)) - != sizeof (head), 0)) - goto out_close; - - if (__builtin_expect (head.version != DB_VERSION, 0) - || __builtin_expect (head.header_size != sizeof (head), 0) - /* This really should not happen but who knows, maybe the update - thread got stuck. */ - || __builtin_expect (! head.nscd_certainly_running - && head.timestamp + MAPPING_TIMEOUT < time (NULL), - 0)) - goto out_close; - - size_t size = (sizeof (head) + roundup (head.module * sizeof (ref_t), ALIGN) - + head.data_size); - - if (__builtin_expect (st.st_size < size, 0)) - goto out_close; - /* The file is large enough, map it now. */ - void *mapping = __mmap (NULL, size, PROT_READ, MAP_SHARED, mapfd, 0); + void *mapping = __mmap (NULL, st.st_size, PROT_READ, MAP_SHARED, mapfd, 0); if (__builtin_expect (mapping != MAP_FAILED, 1)) { - /* Allocate a record for the mapping. */ - struct mapped_database *newp = malloc (sizeof (*newp)); - if (newp == NULL) + /* Check whether the database is correct and up-to-date. */ + struct database_pers_head *head = mapping; + + if (__builtin_expect (head->version != DB_VERSION, 0) + || __builtin_expect (head->header_size != sizeof (*head), 0) + /* This really should not happen but who knows, maybe the update + thread got stuck. */ + || __builtin_expect (! head->nscd_certainly_running + && (head->timestamp + MAPPING_TIMEOUT + < time (NULL)), 0)) { - /* Ugh, after all we went through the memory allocation failed. */ - __munmap (mapping, size); + out_unmap: + __munmap (mapping, st.st_size); goto out_close; } + size_t size = (sizeof (*head) + roundup (head->module * sizeof (ref_t), + ALIGN) + + head->data_size); + + if (__builtin_expect (st.st_size < size, 0)) + goto out_unmap; + + /* Allocate a record for the mapping. */ + struct mapped_database *newp = malloc (sizeof (*newp)); + if (newp == NULL) + /* Ugh, after all we went through the memory allocation failed. */ + goto out_unmap; + newp->head = mapping; - newp->data = ((char *) mapping + head.header_size - + roundup (head.module * sizeof (ref_t), ALIGN)); + newp->data = ((char *) mapping + head->header_size + + roundup (head->module * sizeof (ref_t), ALIGN)); newp->mapsize = size; - newp->datasize = head.data_size; + newp->datasize = head->data_size; /* Set counter to 1 to show it is usable. */ newp->counter = 1; |