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| author |   Jens Axboe <axboe@kernel.dk> | 2020-11-23 09:37:51 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2020-12-09 12:04:01 -0700 |
| commit | ac0648a56c1ff66c1cbf735075ad33a26cbc50de (patch) | |
| tree | d0840931bbfa32badd92a5e51bd02c3048398c96 /fs/io_uring.c | |
| parent | io_uring: fix miscounting ios_left (diff) | |
| download | linux-dev-ac0648a56c1ff66c1cbf735075ad33a26cbc50de.tar.xz linux-dev-ac0648a56c1ff66c1cbf735075ad33a26cbc50de.zip | |
io_uring: use bottom half safe lock for fixed file data
io_file_data_ref_zero() can be invoked from soft-irq from the RCU core,
hence we need to ensure that the file_data lock is bottom half safe. Use
the _bh() variants when grabbing this lock.
Reported-by: syzbot+1f4ba1e5520762c523c6@syzkaller.appspotmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'fs/io_uring.c')
| -rw-r--r-- | fs/io_uring.c | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 91536947ef08..e66888d45778 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -7185,9 +7185,9 @@ static int io_sqe_files_unregister(struct io_ring_ctx *ctx) if (!data) return -ENXIO; - spin_lock(&data->lock); + spin_lock_bh(&data->lock); ref_node = data->node; - spin_unlock(&data->lock); + spin_unlock_bh(&data->lock); if (ref_node) percpu_ref_kill(&ref_node->refs); @@ -7569,7 +7569,7 @@ static void io_file_data_ref_zero(struct percpu_ref *ref) data = ref_node->file_data; ctx = data->ctx; - spin_lock(&data->lock); + spin_lock_bh(&data->lock); ref_node->done = true; while (!list_empty(&data->ref_list)) { @@ -7581,7 +7581,7 @@ static void io_file_data_ref_zero(struct percpu_ref *ref) list_del(&ref_node->node); first_add |= llist_add(&ref_node->llist, &ctx->file_put_llist); } - spin_unlock(&data->lock); + spin_unlock_bh(&data->lock); if (percpu_ref_is_dying(&data->refs)) delay = 0; @@ -7704,9 +7704,9 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, } file_data->node = ref_node; - spin_lock(&file_data->lock); + spin_lock_bh(&file_data->lock); list_add_tail(&ref_node->node, &file_data->ref_list); - spin_unlock(&file_data->lock); + spin_unlock_bh(&file_data->lock); percpu_ref_get(&file_data->refs); return ret; out_fput: @@ -7863,10 +7863,10 @@ static int __io_sqe_files_update(struct io_ring_ctx *ctx, if (needs_switch) { percpu_ref_kill(&data->node->refs); - spin_lock(&data->lock); + spin_lock_bh(&data->lock); list_add_tail(&ref_node->node, &data->ref_list); data->node = ref_node; - spin_unlock(&data->lock); + spin_unlock_bh(&data->lock); percpu_ref_get(&ctx->file_data->refs); } else destroy_fixed_file_ref_node(ref_node); |