From b0b9222f7dd62b19ec702afe295ec71624888e87 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Fabiano=20Fid=C3=AAncio?= Date: Tue, 9 May 2017 13:08:55 +0200 Subject: [PATCH 41/93] IFP: Don't pre-allocate the amount of entries requested MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit By allocating the number of entries when actually copying the list we can avoid situations where users request an enourmous amount of results but the number of results got from the backend are just a few. With this new approach we end up allocating the whole list more frequently but we avoid not returning valid results because the requested number of enties is too big (note that if the amount of results is too big as well, there's nothing much we can do). A simple reproducer for this issue can be the really extreme call: $ dbus-send --system --print-reply --dest=org.freedesktop.sssd.infopipe \ /org/freedesktop/sssd/infopipe/Users \ org.freedesktop.sssd.infopipe.Users.ListByName string:"*" uint32:"-1" The example pasted above would try to allocate an array of MAX_UINT32 size, which would fail directly. Signed-off-by: Fabiano Fidêncio Reviewed-by: Pavel Březina --- src/responder/ifp/ifpsrv_util.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/src/responder/ifp/ifpsrv_util.c b/src/responder/ifp/ifpsrv_util.c index 6eea3354c0d07fe9605f5788f50524115de4b46c..1df646339526186e862dcd09cddd971b77c20a8b 100644 --- a/src/responder/ifp/ifpsrv_util.c +++ b/src/responder/ifp/ifpsrv_util.c @@ -372,7 +372,7 @@ struct ifp_list_ctx *ifp_list_ctx_new(struct sbus_request *sbus_req, list_ctx->ctx = ctx; list_ctx->dom = ctx->rctx->domains; list_ctx->filter = filter; - list_ctx->paths = talloc_zero_array(list_ctx, const char *, limit); + list_ctx->paths = talloc_zero_array(list_ctx, const char *, 1); if (list_ctx->paths == NULL) { talloc_free(list_ctx); return NULL; @@ -389,12 +389,6 @@ errno_t ifp_list_ctx_remaining_capacity(struct ifp_list_ctx *list_ctx, errno_t ret; if (list_ctx->limit == 0) { - list_ctx->paths = talloc_zero_array(list_ctx, const char *, entries); - if (list_ctx->paths == NULL) { - DEBUG(SSSDBG_CRIT_FAILURE, "talloc_zero_array() failed\n"); - ret = ENOMEM; - goto done; - } capacity = entries; goto immediately; } @@ -408,6 +402,14 @@ errno_t ifp_list_ctx_remaining_capacity(struct ifp_list_ctx *list_ctx, } immediately: + talloc_zfree(list_ctx->paths); + list_ctx->paths = talloc_zero_array(list_ctx, const char *, capacity); + if (list_ctx->paths == NULL) { + DEBUG(SSSDBG_CRIT_FAILURE, "talloc_zero_array() failed\n"); + ret = ENOMEM; + goto done; + } + *_capacity = capacity; ret = EOK; -- 2.14.1