kernel/linux.git/drivers/android, branch v5.18.12

binder: Gracefully handle BINDER_TYPE_FDA objects with num_fds=0

2022-04-22T15:22:51+00:00

Some android userspace is sending BINDER_TYPE_FDA objects with num_fds=0. Like the previous patch, this is reproducible when playing a video. Before commit 09184ae9b575 BINDER_TYPE_FDA objects with num_fds=0 were 'correctly handled', as in no fixup was performed. After commit 09184ae9b575 we aggregate fixup and skip regions in binder_ptr_fixup structs and distinguish between the two by using the skip_size field: if it's 0, then it's a fixup, otherwise skip. When processing BINDER_TYPE_FDA objects with num_fds=0 we add a skip region of skip_size=0, and this causes issues because now binder_do_deferred_txn_copies will think this was a fixup region. To address that, return early from binder_translate_fd_array to avoid adding an empty skip region. Fixes: 09184ae9b575 ("binder: defer copies of pre-patched txn data") Acked-by: Todd Kjos Cc: stable Signed-off-by: Alessandro Astone Link: https://lore.kernel.org/r/20220415120015.52684-1-ales.astone@gmail.com Signed-off-by: Greg Kroah-Hartman

binder: Address corner cases in deferred copy and fixup

2022-04-22T15:22:48+00:00

When handling BINDER_TYPE_FDA object we are pushing a parent fixup with a certain skip_size but no scatter-gather copy object, since the copy is handled standalone. If BINDER_TYPE_FDA is the last children the scatter-gather copy loop will never stop to skip it, thus we are left with an item in the parent fixup list. This will trigger the BUG_ON(). This is reproducible in android when playing a video. We receive a transaction that looks like this: obj[0] BINDER_TYPE_PTR, parent obj[1] BINDER_TYPE_PTR, child obj[2] BINDER_TYPE_PTR, child obj[3] BINDER_TYPE_FDA, child Fixes: 09184ae9b575 ("binder: defer copies of pre-patched txn data") Acked-by: Todd Kjos Cc: stable Signed-off-by: Alessandro Astone Link: https://lore.kernel.org/r/20220415120015.52684-2-ales.astone@gmail.com Signed-off-by: Greg Kroah-Hartman

drivers/android: remove redundant ret variable

2022-02-04T14:40:44+00:00

Return value from list_lru_count() directly instead of taking this in another redundant variable. Reported-by: Zeal Robot Signed-off-by: Minghao Chi Signed-off-by: CGEL ZTE Link: https://lore.kernel.org/r/20220104113500.602158-1-chi.minghao@zte.com.cn Signed-off-by: Greg Kroah-Hartman

Merge 5.16-rc8 into char-misc-next

2022-01-03T12:44:38+00:00

We need the fixes in here as well for testing. Signed-off-by: Greg Kroah-Hartman

binder: fix async_free_space accounting for empty parcels

2021-12-21T10:07:34+00:00

In 4.13, commit 74310e06be4d ("android: binder: Move buffer out of area shared with user space") fixed a kernel structure visibility issue. As part of that patch, sizeof(void *) was used as the buffer size for 0-length data payloads so the driver could detect abusive clients sending 0-length asynchronous transactions to a server by enforcing limits on async_free_size. Unfortunately, on the "free" side, the accounting of async_free_space did not add the sizeof(void *) back. The result was that up to 8-bytes of async_free_space were leaked on every async transaction of 8-bytes or less. These small transactions are uncommon, so this accounting issue has gone undetected for several years. The fix is to use "buffer_size" (the allocated buffer size) instead of "size" (the logical buffer size) when updating the async_free_space during the free operation. These are the same except for this corner case of asynchronous transactions with payloads < 8 bytes. Fixes: 74310e06be4d ("android: binder: Move buffer out of area shared with user space") Signed-off-by: Todd Kjos Cc: stable@vger.kernel.org # 4.14+ Link: https://lore.kernel.org/r/20211220190150.2107077-1-tkjos@google.com Signed-off-by: Greg Kroah-Hartman

binder: use proper cacheflush header file

2021-12-21T09:11:27+00:00

binder.c uses instead of . Hence change cacheflush header file to proper one. This change also avoid warning from checkpatch that shown below: WARNING: Use #include instead of Signed-off-by: Ajith P V Link: https://lore.kernel.org/r/20211215132018.31522-1-ajithpv.linux@gmail.com Signed-off-by: Greg Kroah-Hartman

Merge v5.15-rc5 into char-misc-next

2021-12-13T09:17:10+00:00

We need the fixes in here as well, and also resolve some merge conflicts in: drivers/misc/eeprom/at25.c Signed-off-by: Greg Kroah-Hartman

binder: use wake_up_pollfree()

2021-12-09T18:49:56+00:00

wake_up_poll() uses nr_exclusive=1, so it's not guaranteed to wake up all exclusive waiters. Yet, POLLFREE *must* wake up all waiters. epoll and aio poll are fortunately not affected by this, but it's very fragile. Thus, the new function wake_up_pollfree() has been introduced. Convert binder to use wake_up_pollfree(). Reported-by: Linus Torvalds Fixes: f5cb779ba163 ("ANDROID: binder: remove waitqueue when thread exits.") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20211209010455.42744-3-ebiggers@kernel.org Signed-off-by: Eric Biggers

binder: fix pointer cast warning

2021-12-08T16:30:03+00:00

binder_uintptr_t is not the same as uintptr_t, so converting it into a pointer requires a second cast: drivers/android/binder.c: In function 'binder_translate_fd_array': drivers/android/binder.c:2511:28: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast] 2511 | sender_ufda_base = (void __user *)sender_uparent->buffer + fda->parent_offset; | ^ Fixes: 656e01f3ab54 ("binder: read pre-translated fds from sender buffer") Acked-by: Todd Kjos Acked-by: Randy Dunlap # build-tested Acked-by: Christian Brauner Signed-off-by: Arnd Bergmann Link: https://lore.kernel.org/r/20211207122448.1185769-1-arnd@kernel.org Signed-off-by: Greg Kroah-Hartman

binder: defer copies of pre-patched txn data

2021-12-03T13:29:39+00:00

BINDER_TYPE_PTR objects point to memory areas in the source process to be copied into the target buffer as part of a transaction. This implements a scatter- gather model where non-contiguous memory in a source process is "gathered" into a contiguous region in the target buffer. The data can include pointers that must be fixed up to correctly point to the copied data. To avoid making source process pointers visible to the target process, this patch defers the copy until the fixups are known and then copies and fixeups are done together. There is a special case of BINDER_TYPE_FDA which applies the fixup later in the target process context. In this case the user data is skipped (so no untranslated fds become visible to the target). Reviewed-by: Martijn Coenen Signed-off-by: Todd Kjos Link: https://lore.kernel.org/r/20211130185152.437403-5-tkjos@google.com Signed-off-by: Greg Kroah-Hartman