* Re: [PATCH] rcu: Annotate struct kvfree_rcu_bulk_data with __counted_by()
2024-08-07 9:55 [PATCH] rcu: Annotate struct kvfree_rcu_bulk_data with __counted_by() Thorsten Blum
@ 2024-08-07 15:29 ` Gustavo A. R. Silva
2024-08-07 15:35 ` Uladzislau Rezki
2024-08-08 18:02 ` Paul E. McKenney
2 siblings, 0 replies; 4+ messages in thread
From: Gustavo A. R. Silva @ 2024-08-07 15:29 UTC (permalink / raw)
To: Thorsten Blum, paulmck, frederic, neeraj.upadhyay, joel, josh,
boqun.feng, urezki, rostedt, mathieu.desnoyers, jiangshanlai,
qiang.zhang1211, kees, gustavoars
Cc: rcu, linux-kernel, linux-hardening
On 07/08/24 03:55, Thorsten Blum wrote:
> Add the __counted_by compiler attribute to the flexible array member
> records to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and
> CONFIG_FORTIFY_SOURCE.
>
> Increment nr_records before adding a new pointer to the records array.
>
Looks good.
> Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Thanks
--
Gustavo
> ---
> kernel/rcu/tree.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
> index e641cc681901..76d8d75dd8b3 100644
> --- a/kernel/rcu/tree.c
> +++ b/kernel/rcu/tree.c
> @@ -3227,7 +3227,7 @@ struct kvfree_rcu_bulk_data {
> struct list_head list;
> struct rcu_gp_oldstate gp_snap;
> unsigned long nr_records;
> - void *records[];
> + void *records[] __counted_by(nr_records);
> };
>
> /*
> @@ -3767,7 +3767,8 @@ add_ptr_to_bulk_krc_lock(struct kfree_rcu_cpu **krcp,
> }
>
> // Finally insert and update the GP for this page.
> - bnode->records[bnode->nr_records++] = ptr;
> + bnode->nr_records++;
> + bnode->records[bnode->nr_records - 1] = ptr;
> get_state_synchronize_rcu_full(&bnode->gp_snap);
> atomic_inc(&(*krcp)->bulk_count[idx]);
>
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] rcu: Annotate struct kvfree_rcu_bulk_data with __counted_by()
2024-08-07 9:55 [PATCH] rcu: Annotate struct kvfree_rcu_bulk_data with __counted_by() Thorsten Blum
2024-08-07 15:29 ` Gustavo A. R. Silva
@ 2024-08-07 15:35 ` Uladzislau Rezki
2024-08-08 18:02 ` Paul E. McKenney
2 siblings, 0 replies; 4+ messages in thread
From: Uladzislau Rezki @ 2024-08-07 15:35 UTC (permalink / raw)
To: Thorsten Blum
Cc: paulmck, frederic, neeraj.upadhyay, joel, josh, boqun.feng,
urezki, rostedt, mathieu.desnoyers, jiangshanlai, qiang.zhang1211,
kees, gustavoars, rcu, linux-kernel, linux-hardening
On Wed, Aug 07, 2024 at 11:55:00AM +0200, Thorsten Blum wrote:
> Add the __counted_by compiler attribute to the flexible array member
> records to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and
> CONFIG_FORTIFY_SOURCE.
>
> Increment nr_records before adding a new pointer to the records array.
>
> Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
> ---
> kernel/rcu/tree.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
> index e641cc681901..76d8d75dd8b3 100644
> --- a/kernel/rcu/tree.c
> +++ b/kernel/rcu/tree.c
> @@ -3227,7 +3227,7 @@ struct kvfree_rcu_bulk_data {
> struct list_head list;
> struct rcu_gp_oldstate gp_snap;
> unsigned long nr_records;
> - void *records[];
> + void *records[] __counted_by(nr_records);
> };
>
> /*
> @@ -3767,7 +3767,8 @@ add_ptr_to_bulk_krc_lock(struct kfree_rcu_cpu **krcp,
> }
>
> // Finally insert and update the GP for this page.
> - bnode->records[bnode->nr_records++] = ptr;
> + bnode->nr_records++;
> + bnode->records[bnode->nr_records - 1] = ptr;
> get_state_synchronize_rcu_full(&bnode->gp_snap);
> atomic_inc(&(*krcp)->bulk_count[idx]);
>
> --
> 2.45.2
>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
--
Uladzislau Rezki
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] rcu: Annotate struct kvfree_rcu_bulk_data with __counted_by()
2024-08-07 9:55 [PATCH] rcu: Annotate struct kvfree_rcu_bulk_data with __counted_by() Thorsten Blum
2024-08-07 15:29 ` Gustavo A. R. Silva
2024-08-07 15:35 ` Uladzislau Rezki
@ 2024-08-08 18:02 ` Paul E. McKenney
2 siblings, 0 replies; 4+ messages in thread
From: Paul E. McKenney @ 2024-08-08 18:02 UTC (permalink / raw)
To: Thorsten Blum
Cc: frederic, neeraj.upadhyay, joel, josh, boqun.feng, urezki,
rostedt, mathieu.desnoyers, jiangshanlai, qiang.zhang1211, kees,
gustavoars, rcu, linux-kernel, linux-hardening
On Wed, Aug 07, 2024 at 11:55:00AM +0200, Thorsten Blum wrote:
> Add the __counted_by compiler attribute to the flexible array member
> records to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and
> CONFIG_FORTIFY_SOURCE.
>
> Increment nr_records before adding a new pointer to the records array.
>
> Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
> ---
> kernel/rcu/tree.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
> index e641cc681901..76d8d75dd8b3 100644
> --- a/kernel/rcu/tree.c
> +++ b/kernel/rcu/tree.c
> @@ -3227,7 +3227,7 @@ struct kvfree_rcu_bulk_data {
> struct list_head list;
> struct rcu_gp_oldstate gp_snap;
> unsigned long nr_records;
> - void *records[];
> + void *records[] __counted_by(nr_records);
> };
>
> /*
> @@ -3767,7 +3767,8 @@ add_ptr_to_bulk_krc_lock(struct kfree_rcu_cpu **krcp,
> }
>
> // Finally insert and update the GP for this page.
> - bnode->records[bnode->nr_records++] = ptr;
> + bnode->nr_records++;
> + bnode->records[bnode->nr_records - 1] = ptr;
> get_state_synchronize_rcu_full(&bnode->gp_snap);
> atomic_inc(&(*krcp)->bulk_count[idx]);
>
> --
> 2.45.2
>
^ permalink raw reply [flat|nested] 4+ messages in thread