OP-TEE March 2026

op-tee@lists.trustedfirmware.org

23 participants
23 discussions

[RFT PATCH v2] tee: shm: Remove refcounting of kernel pages

by Sumit Garg

From: Matthew Wilcox <willy(a)infradead.org> Earlier TEE subsystem assumed to refcount all the memory pages to be shared with TEE implementation to be refcounted. However, the slab allocations within the kernel don't allow refcounting kernel pages. It is rather better to trust the kernel clients to not free pages while being shared with TEE implementation. Hence, remove refcounting of kernel pages from register_shm_helper() API. Fixes: b9c0e49abfca ("mm: decline to manipulate the refcount on a slab page") Reported-by: Marco Felsch <m.felsch(a)pengutronix.de> Reported-by: Sven Püschel <s.pueschel(a)pengutronix.de> Signed-off-by: Matthew Wilcox <willy(a)infradead.org> Co-developed-by: Sumit Garg <sumit.garg(a)oss.qualcomm.com> Signed-off-by: Sumit Garg <sumit.garg(a)oss.qualcomm.com> --- Changes in v2: - Attribute Matthew as the author of this patch. - Fix check for user pages. drivers/tee/tee_shm.c | 27 --------------------------- 1 file changed, 27 deletions(-) diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c index 4a47de4bb2e5..898707ca21a8 100644 --- a/drivers/tee/tee_shm.c +++ b/drivers/tee/tee_shm.c @@ -23,29 +23,11 @@ struct tee_shm_dma_mem { struct page *page; }; -static void shm_put_kernel_pages(struct page **pages, size_t page_count) -{ - size_t n; - - for (n = 0; n < page_count; n++) - put_page(pages[n]); -} - -static void shm_get_kernel_pages(struct page **pages, size_t page_count) -{ - size_t n; - - for (n = 0; n < page_count; n++) - get_page(pages[n]); -} - static void release_registered_pages(struct tee_shm *shm) { if (shm->pages) { if (shm->flags & TEE_SHM_USER_MAPPED) unpin_user_pages(shm->pages, shm->num_pages); - else - shm_put_kernel_pages(shm->pages, shm->num_pages); kfree(shm->pages); } @@ -477,13 +459,6 @@ register_shm_helper(struct tee_context *ctx, struct iov_iter *iter, u32 flags, goto err_put_shm_pages; } - /* - * iov_iter_extract_kvec_pages does not get reference on the pages, - * get a reference on them. - */ - if (iov_iter_is_kvec(iter)) - shm_get_kernel_pages(shm->pages, num_pages); - shm->offset = off; shm->size = len; shm->num_pages = num_pages; @@ -499,8 +474,6 @@ register_shm_helper(struct tee_context *ctx, struct iov_iter *iter, u32 flags, err_put_shm_pages: if (!iov_iter_is_kvec(iter)) unpin_user_pages(shm->pages, shm->num_pages); - else - shm_put_kernel_pages(shm->pages, shm->num_pages); err_free_shm_pages: kfree(shm->pages); err_free_shm: -- 2.51.0

4 months

[PATCH 0/3] OP-TEE/OP-TEE drivers: simplify context matches

by Rouven Czerwinski via B4 Relay

Both the OP-TEE core and some OP-TEE drivers use an if/else expression to check a boolean which can instead be returned directly. Implement this change. --- Rouven Czerwinski (3): optee: simplify OP-TEE context match hwrng: optee - simplify OP-TEE context match rtc: optee: simplify OP-TEE context match drivers/char/hw_random/optee-rng.c | 5 +---- drivers/rtc/rtc-optee.c | 5 +---- drivers/tee/optee/device.c | 5 +---- 3 files changed, 3 insertions(+), 12 deletions(-) --- base-commit: 63804fed149a6750ffd28610c5c1c98cce6bd377 change-id: 20260126-optee-simplify-context-match-d5b3467bfacc Best regards, -- Rouven Czerwinski <rouven.czerwinski(a)linaro.org>

4 months, 1 week

Re: [PATCH v5] tee: optee: prevent use-after-free when the client exits before the supplicant

by Yuanjia Yeh

Hi all, We can reproduce the reported use-after-free issue on our platform via an overnight reboot test The verifications are listed as the following - With v2 + Michael Wu's patch: Issue resolved. - With v4: Race condition observation and already report to Amir - With v5: Race fixed. Stable in our tests, including: xtest + reboot loop (300 cycles) continuous reboot test (1000 cycles) No regressions observed with v5. If there are no other concerns, we recommend adopting v5. If needed, please add the following tag: Tested-by: Ox Yeh <ox.yeh(a)mediatek.com> Yuanjia Yeh

4 months, 2 weeks

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OP-TEE March 2026