5.15-stable review patch. If anyone has any objections, please let me know.
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From: Chen Ridong chenridong@huawei.com
[ Upstream commit ae154202cc6a189b035359f3c4e143d5c24d5352 ]
Add helpers for pd to get/put refcnt to make code consice.
Signed-off-by: Chen Ridong chenridong@huawei.com Acked-by: Daniel Jordan daniel.m.jordan@oracle.com Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Stable-dep-of: dd7d37ccf6b1 ("padata: avoid UAF for reorder_work") Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/padata.c | 27 ++++++++++++++++++++------- 1 file changed, 20 insertions(+), 7 deletions(-)
diff --git a/kernel/padata.c b/kernel/padata.c index 9608a269f66f2..b5a1a31ce6c11 100644 --- a/kernel/padata.c +++ b/kernel/padata.c @@ -47,6 +47,22 @@ struct padata_mt_job_state { static void padata_free_pd(struct parallel_data *pd); static void __init padata_mt_helper(struct work_struct *work);
+static inline void padata_get_pd(struct parallel_data *pd) +{ + refcount_inc(&pd->refcnt); +} + +static inline void padata_put_pd_cnt(struct parallel_data *pd, int cnt) +{ + if (refcount_sub_and_test(cnt, &pd->refcnt)) + padata_free_pd(pd); +} + +static inline void padata_put_pd(struct parallel_data *pd) +{ + padata_put_pd_cnt(pd, 1); +} + static int padata_index_to_cpu(struct parallel_data *pd, int cpu_index) { int cpu, target_cpu; @@ -198,7 +214,7 @@ int padata_do_parallel(struct padata_shell *ps, if ((pinst->flags & PADATA_RESET)) goto out;
- refcount_inc(&pd->refcnt); + padata_get_pd(pd); padata->pd = pd; padata->cb_cpu = *cb_cpu;
@@ -372,8 +388,7 @@ static void padata_serial_worker(struct work_struct *serial_work) } local_bh_enable();
- if (refcount_sub_and_test(cnt, &pd->refcnt)) - padata_free_pd(pd); + padata_put_pd_cnt(pd, cnt); }
/** @@ -670,8 +685,7 @@ static int padata_replace(struct padata_instance *pinst) synchronize_rcu();
list_for_each_entry_continue_reverse(ps, &pinst->pslist, list) - if (refcount_dec_and_test(&ps->opd->refcnt)) - padata_free_pd(ps->opd); + padata_put_pd(ps->opd);
pinst->flags &= ~PADATA_RESET;
@@ -1119,8 +1133,7 @@ void padata_free_shell(struct padata_shell *ps) mutex_lock(&ps->pinst->lock); list_del(&ps->list); pd = rcu_dereference_protected(ps->pd, 1); - if (refcount_dec_and_test(&pd->refcnt)) - padata_free_pd(pd); + padata_put_pd(pd); mutex_unlock(&ps->pinst->lock);
kfree(ps);