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| author | Shivank Garg <shivankg@amd.com> | 2026-08-22 19:22:05 +0000 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2026-09-09 17:51:44 +0530 |
| commit | e873c74132f0c5f1452816cd9bb26208f0bba1e1 (patch) | |
| tree | cc1ce1567f5b982359331863ebd9da38741f8d2e /io_uring/sqpoll.h | |
| download | linux-stable-e873c74132f0c5f1452816cd9bb26208f0bba1e1.tar.gz linux-stable-e873c74132f0c5f1452816cd9bb26208f0bba1e1.zip | |
dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel()grafted
When dma_device_put() drops the last reference on chan->device->ref,
dma_device_release() runs and may free the dma_device along with its
channels.
dma_chan_put() then still reads chan->device->owner via
dma_chan_to_owner() for the trailing module_put(). KASAN catches it:
slab-use-after-free in dma_chan_put+0x3e6/0x4c0
Read of size 8 by task insmod/6319
Freed by task 6319:
kfree+0x225/0x470
dma_chan_put+0x395/0x4c0
dmaengine_put+0xf8/0x160
Cache the module owner in dma_chan_put() before the put so the trailing
module_put() does not need chan->device.
Fixes: 8ad342a86359 ("dmaengine: Add reference counting to dma_device struct")
Suggested-by: Sashiko <sashiko-bot@kernel.org>
Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Shivank Garg <shivankg@amd.com>
Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'io_uring/sqpoll.h')
| -rw-r--r-- | io_uring/sqpoll.h | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/io_uring/sqpoll.h b/io_uring/sqpoll.h new file mode 100644 index 000000000..fd2f6f29b --- /dev/null +++ b/io_uring/sqpoll.h @@ -0,0 +1,38 @@ +// SPDX-License-Identifier: GPL-2.0 + +struct io_sq_data { + refcount_t refs; + atomic_t park_pending; + struct mutex lock; + + /* ctx's that are using this sqd */ + struct list_head ctx_list; + + struct task_struct __rcu *thread; + struct wait_queue_head wait; + + unsigned sq_thread_idle; + int sq_cpu; + pid_t task_pid; + pid_t task_tgid; + + u64 work_time; + unsigned long state; + struct completion exited; +}; + +int io_sq_offload_create(struct io_ring_ctx *ctx, struct io_uring_params *p); +void io_sq_thread_finish(struct io_ring_ctx *ctx); +void io_sq_thread_stop(struct io_sq_data *sqd); +void io_sq_thread_park(struct io_sq_data *sqd); +void io_sq_thread_unpark(struct io_sq_data *sqd); +void io_put_sq_data(struct io_sq_data *sqd); +void io_sqpoll_wait_sq(struct io_ring_ctx *ctx); +int io_sqpoll_wq_cpu_affinity(struct io_ring_ctx *ctx, cpumask_var_t mask); +u64 io_sq_cpu_usec(struct task_struct *tsk); + +static inline struct task_struct *sqpoll_task_locked(struct io_sq_data *sqd) +{ + return rcu_dereference_protected(sqd->thread, + lockdep_is_held(&sqd->lock)); +} |