binder_validate_ptr(9)

💅 binder_validate_ptr(9) — the Kernel API Manual glow-up ✨

okay bestie, welcome to the Kernel API Manual, section 9, and today's main character is binder_validate_ptr(9) 🎀 she's a little validation girlie and honestly? she ate.

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🌸 NAME 🌸

binder_validate_ptr — validates a binder_buffer_object inside a binder_buffer. that's it, that's the whole vibe 💖

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✨ SYNOPSIS ✨

struct binder_buffer_object * binder_validate_ptr (struct binder_proc
*proc , struct binder_buffer *b , struct binder_object *object ,
binder_size_t index , binder_size_t start_offset , binder_size_t
*object_offsetp , binder_size_t num_valid );

like yes she takes seven arguments, she's high maintenance, but she's worth it 🫶

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🦋 ARGUMENTS 🦋

• proc — the binder_proc that owns the buffer. the landlord, basically 👑
• b — the binder_buffer that's holding the object. the container, the moment, the venue 💅
• object — the struct binder_object we're reading into. this is where the tea gets poured 🍓
• index — index into the offset array where the binder_buffer_object is chillin' 🔥
• start_offset — points to the start of the offset array. the origin story, iykyk ⭐
• object_offsetp — the offset of the object read from b 😭
• num_valid — how many valid offsets live in the offset array. the headcount, no cap 💀

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🌈 RETURN 🌈

okay so here's the tea, bestie, listen up 🧚

if index is within the valid range of the offset array described by start and num_valid, and there's a valid binder_buffer_object at the offset found in index index of the offset array — then that object gets returned. slay ✨

otherwise? NULL. that's it. she's not mad, she's just done 🙈

BIG CAVEAT, do not skip this — the offset found in index index itself is not verified. this function assumes that num_valid elements from start were previously verified to have valid offsets. so like... if you didn't do your homework earlier, that's on you fr fr 💀

and if object_offsetp is non-NULL, then the offset within b is written to it 🎀

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💜 SEE ALSO 💜

Kernel file ./drivers/android/binder.c, plus the whole friend group 👑

• binder_proc_lock(9)
• binder_proc_unlock(9)
• binder_inner_proc_lock(9)
• binder_inner_proc_unlock(9)
• binder_node_lock(9)
• binder_node_unlock(9)
• binder_node_inner_lock(9)
• binder_node_inner_unlock(9)
• binder_worklist_empty(9)
• binder_enqueue_work_ilocked(9)
• binder_enqueue_deferred_thread_work_ilocked(9)
• binder_enqueue_thread_work_ilocked(9)
• binder_enqueue_thread_work(9)
• binder_dequeue_work(9)
• binder_select_thread_ilocked(9)
• binder_wakeup_thread_ilocked(9)
• binder_inc_node_tmpref(9)
• binder_dec_node_tmpref(9)
• binder_get_ref_for_node_olocked(9)
• binder_inc_ref_olocked(9)
• binder_dec_ref_olocked(9)
• binder_get_node_from_ref(9)
• binder_free_ref(9)
• binder_update_ref_for_handle(9)
• binder_dec_ref_for_handle(9)
• binder_inc_ref_for_node(9)
• binder_thread_dec_tmpref(9)
• binder_proc_dec_tmpref(9)
• binder_get_txn_from(9)
• binder_get_txn_from_and_acq_inner(9)
• binder_free_txn_fixups(9)
• binder_cleanup_transaction(9)
• binder_get_object(9)
• binder_validate_fixup(9)
• struct binder_task_work_cb(9)
• binder_do_fd_close(9)
• binder_deferred_fd_close(9)
• struct binder_ptr_fixup(9)
• struct binder_sg_copy(9)
• binder_do_deferred_txn_copies(9)
• binder_cleanup_deferred_txn_lists(9)
• binder_defer_copy(9)
• binder_add_fixup(9)
• binder_can_update_transaction(9)
• binder_find_outdated_transaction_ilocked(9)
• binder_proc_transaction(9)
• binder_get_node_refs_for_txn(9)
• binder_netlink_report(9)
• binder_free_buf(9)
• binder_apply_fd_fixups(9)
• print_next_binder_node_ilocked(9)

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and that's the whole page, bestie, no notes 💖 this icon lives in ./drivers/android, dated October 2026, and she'll always answer to binder_validate_ptr(9) 🦋✨ go forth and validate those pointers, periodt 💅