Amirreza Zarrabi 416259cb5b tee: optee: prevent use-after-free when the client exits before the supplicant ...

[ Upstream commit 387a926ee1 ]

Commit 70b0d6b0a1 ("tee: optee: Fix supplicant wait loop") made the
client wait as killable so it can be interrupted during shutdown or
after a supplicant crash. This changes the original lifetime expectations:
the client task can now terminate while the supplicant is still processing
its request.

If the client exits first it removes the request from its queue and
kfree()s it, while the request ID remains in supp->idr. A subsequent
lookup on the supplicant path then dereferences freed memory, leading to
a use-after-free.

Serialise access to the request with supp->mutex:

  * Hold supp->mutex in optee_supp_recv() and optee_supp_send() while
    looking up and touching the request.
  * Let optee_supp_thrd_req() notice that the client has terminated and
    signal optee_supp_send() accordingly.

With these changes the request cannot be freed while the supplicant still
has a reference, eliminating the race.

Fixes: 70b0d6b0a1 ("tee: optee: Fix supplicant wait loop")
Signed-off-by: Amirreza Zarrabi <amirreza.zarrabi@oss.qualcomm.com>
Tested-by: Ox Yeh <ox.yeh@mediatek.com>
Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

2026-06-19 13:21:33 +02:00

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amdtee

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optee

tee: optee: prevent use-after-free when the client exits before the supplicant

2026-06-19 13:21:33 +02:00

Kconfig

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Makefile

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tee_core.c

tee: allow a driver to allocate a tee_device without a pool

2025-12-07 06:08:09 +09:00

tee_private.h

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tee_shm_pool.c

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tee_shm.c

tee: fix NULL pointer dereference in tee_shm_put

2025-09-09 18:45:18 +02:00