autofs-5.1.1 - properly handle errors in lookup_nss_mount From: Jeff Mahoney The 'result' variable is initialized to 0 and inconsistently set in the main while loop. If the map is expired, the strdup("ldap") fails, or we end up bailing on an sss source with an amd map, and we're processing the only map in the list or check_nss_result indicates that we should continue even when we have NSS_STATUS_SUCCESS, we'll return success when a failure has occured. Without this change, the end result is still a failure for the user. The caller attempting to traverse the map will eventually receive ELOOP once the kernel has reached its internal automount/link follow limit. We will have just wasted a bunch of time in the interim. This behavior was observed on a system that was affected by the missing map->age update fixed in the previous patch. --- daemon/lookup.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/daemon/lookup.c b/daemon/lookup.c index 0129f75..173f53e 100644 --- a/daemon/lookup.c +++ b/daemon/lookup.c @@ -1073,7 +1073,7 @@ int lookup_nss_mount(struct autofs_point *ap, struct map_source *source, const c struct nss_source *this; struct map_source *map; enum nsswitch_status status; - int result = 0; + int result = NSS_STATUS_UNKNOWN; /* * For each map source (ie. each entry for the mount @@ -1092,6 +1092,7 @@ int lookup_nss_mount(struct autofs_point *ap, struct map_source *source, const c * the map entry was last updated. */ if (entry->age > map->age) { + status = NSS_STATUS_UNAVAIL; map = map->next; continue; } @@ -1113,6 +1114,7 @@ int lookup_nss_mount(struct autofs_point *ap, struct map_source *source, const c char *tmp = strdup("ldap"); if (!tmp) { map = map->next; + status = NSS_STATUS_TRYAGAIN; continue; } map->type = tmp; @@ -1145,6 +1147,7 @@ int lookup_nss_mount(struct autofs_point *ap, struct map_source *source, const c !strcmp(this->source, "sss")) { warn(ap->logopt, "source sss is not available for amd maps."); + result = NSS_STATUS_UNAVAIL; continue; }