STRUCT TEE_IOCTL_BUF_DATA(9)

💅 struct tee_ioctl_buf_data(9) — the Kernel API Manual, bestie edition ✨

okay so this is a page straight out of the Kernel API Manual and it's literally about one little struct that just wants to hold a buffer of variable size. tiny, iconic, does its job. let's get into it 🫶

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✨ NAME ✨

struct tee_ioctl_buf_data — Variable sized buffer 💖

like, the name says it all. it's a buffer. the size can vary. she contains multitudes.

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🦋 SYNOPSIS 🦋

struct tee_ioctl_buf_data {
    __u64 buf_ptr;
    __u64 buf_len;
 };

that's it. two fields. no cap, that's the whole struct. she's minimal and she's thriving ✨

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🎀 Members 🎀

• buf_ptr — [in] A __user pointer to a buffer. yes bestie, __user — it's a userspace pointer, so treat it with the respect (and the careful copy_from_user-energy) it deserves 💅
• buf_len — [in] Length of the buffer above. it's giving "how much of that buffer are we actually talking about" 📏

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🌸 Description 🌸

so this struct is used as the argument for TEE_IOC_OPEN_SESSION, TEE_IOC_INVOKE, TEE_IOC_SUPPL_RECV, and TEE_IOC_SUPPL_SEND below. that's the whole vibe — she's the arg carrier, the little envelope that says "here's a pointer, here's how long it is" 🎀

fr fr the pointer and length are the entire personality here. don't overthink her.

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👑 SEE ALSO 👑

okay this list is LONG and honestly kind of a flex. buckle up buttercup 💅

• Kernel file ./include/uapi/linux/tee.h
• struct tee_ioctl_version_data(9)
• TEE_IOC_VERSION(9)
• struct tee_ioctl_shm_alloc_data(9)
• TEE_IOC_SHM_ALLOC(9)
• struct tee_ioctl_param(9)
• struct tee_ioctl_open_session_arg(9)
• TEE_IOC_OPEN_SESSION(9)
• struct tee_ioctl_invoke_arg(9)
• TEE_IOC_INVOKE(9)
• struct tee_ioctl_cancel_arg(9)
• TEE_IOC_CANCEL(9)
• struct tee_ioctl_close_session_arg(9)
• TEE_IOC_CLOSE_SESSION(9)
• struct tee_iocl_supp_recv_arg(9)
• TEE_IOC_SUPPL_RECV(9)
• struct tee_iocl_supp_send_arg(9)
• TEE_IOC_SUPPL_SEND(9)
• struct tee_ioctl_shm_register_data(9)
• struct tee_ioctl_shm_register_fd_data(9)
• TEE_IOC_SHM_REGISTER_FD(9)
• TEE_IOC_SHM_REGISTER(9)
• struct tee_ioctl_object_invoke_arg(9)

like… the whole TEE ioctl friend group showed up. obsessed 😭🔥

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and that's the tea, bestie 🍓 this one lives under ./include/uapi/linux in the kernel tree, dated October 2026, and it's filed in the manual as struct tee_ioctl_buf_data(9). go read the rest of the TEE pages, ily, bye 💜✨