diff options
| -rw-r--r-- | ChangeLog | 12 | ||||
| -rw-r--r-- | nscd/netgroupcache.c | 42 |
2 files changed, 41 insertions, 13 deletions
@@ -1,3 +1,15 @@ +2018-08-28 Florian Weimer <fweimer@redhat.com> + + [BZ #23520] + nscd: Fix use-after-free in addgetnetgrentX and its callers. + * nscd/netgroupcache.c + (addgetnetgrentX): Add tofreep parameter. Do not free + heap-allocated buffer. + (addinnetgrX): Free buffer allocated bt addgetnetgrentX. + (addgetnetgrentX_ignore): New function. + (addgetnetgrent): Call it. + (readdgetnetgrent): Likewise. + 2018-08-28 Rajalakshmi Srinivasaraghavan <raji@linux.vnet.ibm.com> * string/memmem.c: Use memcmp for first match. diff --git a/nscd/netgroupcache.c b/nscd/netgroupcache.c index 2b35389..87059fb 100644 --- a/nscd/netgroupcache.c +++ b/nscd/netgroupcache.c @@ -113,7 +113,8 @@ do_notfound (struct database_dyn *db, int fd, request_header *req, static time_t addgetnetgrentX (struct database_dyn *db, int fd, request_header *req, const char *key, uid_t uid, struct hashentry *he, - struct datahead *dh, struct dataset **resultp) + struct datahead *dh, struct dataset **resultp, + void **tofreep) { if (__glibc_unlikely (debug_level > 0)) { @@ -139,6 +140,7 @@ addgetnetgrentX (struct database_dyn *db, int fd, request_header *req, size_t group_len = strlen (key) + 1; struct name_list *first_needed = alloca (sizeof (struct name_list) + group_len); + *tofreep = NULL; if (netgroup_database == NULL && __nss_database_lookup ("netgroup", NULL, NULL, &netgroup_database)) @@ -151,6 +153,7 @@ addgetnetgrentX (struct database_dyn *db, int fd, request_header *req, memset (&data, '\0', sizeof (data)); buffer = xmalloc (buflen); + *tofreep = buffer; first_needed->next = first_needed; memcpy (first_needed->name, key, group_len); data.needed_groups = first_needed; @@ -439,8 +442,6 @@ addgetnetgrentX (struct database_dyn *db, int fd, request_header *req, } out: - free (buffer); - *resultp = dataset; return timeout; @@ -477,8 +478,12 @@ addinnetgrX (struct database_dyn *db, int fd, request_header *req, group, group_len, db, uid); time_t timeout; + void *tofree; if (result != NULL) - timeout = result->head.timeout; + { + timeout = result->head.timeout; + tofree = NULL; + } else { request_header req_get = @@ -487,7 +492,7 @@ addinnetgrX (struct database_dyn *db, int fd, request_header *req, .key_len = group_len }; timeout = addgetnetgrentX (db, -1, &req_get, group, uid, NULL, NULL, - &result); + &result, &tofree); } struct indataset @@ -560,7 +565,7 @@ addinnetgrX (struct database_dyn *db, int fd, request_header *req, ++dh->nreloads; if (cacheable) pthread_rwlock_unlock (&db->lock); - return timeout; + goto out; } if (he == NULL) @@ -596,17 +601,30 @@ addinnetgrX (struct database_dyn *db, int fd, request_header *req, dh->usable = false; } + out: + free (tofree); return timeout; } +static time_t +addgetnetgrentX_ignore (struct database_dyn *db, int fd, request_header *req, + const char *key, uid_t uid, struct hashentry *he, + struct datahead *dh) +{ + struct dataset *ignore; + void *tofree; + time_t timeout = addgetnetgrentX (db, fd, req, key, uid, he, dh, + &ignore, &tofree); + free (tofree); + return timeout; +} + void addgetnetgrent (struct database_dyn *db, int fd, request_header *req, void *key, uid_t uid) { - struct dataset *ignore; - - addgetnetgrentX (db, fd, req, key, uid, NULL, NULL, &ignore); + addgetnetgrentX_ignore (db, fd, req, key, uid, NULL, NULL); } @@ -619,10 +637,8 @@ readdgetnetgrent (struct database_dyn *db, struct hashentry *he, .type = GETNETGRENT, .key_len = he->len }; - struct dataset *ignore; - - return addgetnetgrentX (db, -1, &req, db->data + he->key, he->owner, he, dh, - &ignore); + return addgetnetgrentX_ignore + (db, -1, &req, db->data + he->key, he->owner, he, dh); } |