From 19526d092ceb32d619fce73fe0bdca4370890124 Mon Sep 17 00:00:00 2001 From: Marijn Suijten Date: Sun, 22 Aug 2021 19:44:10 +0200 Subject: [PATCH] opp: core: Check for pending links before reading required_opp pointers Commit 4fa82a87ba55 ("opp: Allow required-opps to be used for non genpd use cases") dereferences the pointers in required_opp_tables but these might be set to an ERR_PTR if the list still has lazy links pending, resulting in segfaults. Prior to this patch IS_ERR was also checked on required_opp_tables[i] before reading ->is_genpd inside _opp_table_alloc_required_tables, which is at the same time the predicate to add this table to the lazy list. This segfault is solved by reordering the checks to bail on lazy pending tables before reading ->is_genpd. Fixes: 4fa82a87ba55 ("opp: Allow required-opps to be used for non genpd use cases") Reviewed-by: AngeloGioacchino Del Regno Signed-off-by: Marijn Suijten Signed-off-by: Viresh Kumar --- drivers/opp/core.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/opp/core.c b/drivers/opp/core.c index 5543c54..04b4691 100644 --- a/drivers/opp/core.c +++ b/drivers/opp/core.c @@ -893,6 +893,10 @@ static int _set_required_opps(struct device *dev, if (!required_opp_tables) return 0; + /* required-opps not fully initialized yet */ + if (lazy_linking_pending(opp_table)) + return -EBUSY; + /* * We only support genpd's OPPs in the "required-opps" for now, as we * don't know much about other use cases. Error out if the required OPP @@ -903,10 +907,6 @@ static int _set_required_opps(struct device *dev, return -ENOENT; } - /* required-opps not fully initialized yet */ - if (lazy_linking_pending(opp_table)) - return -EBUSY; - /* Single genpd case */ if (!genpd_virt_devs) return _set_required_opp(dev, dev, opp, 0); -- 2.7.4