linux/drivers/android
Alessandro Astone ef38de9217 binder: Gracefully handle BINDER_TYPE_FDA objects with num_fds=0
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 09184ae9b5 BINDER_TYPE_FDA objects with num_fds=0
were 'correctly handled', as in no fixup was performed.

After commit 09184ae9b5 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: 09184ae9b5 ("binder: defer copies of pre-patched txn data")
Acked-by: Todd Kjos <tkjos@google.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Alessandro Astone <ales.astone@gmail.com>
Link: https://lore.kernel.org/r/20220415120015.52684-1-ales.astone@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-22 17:22:51 +02:00
..
binder_alloc_selftest.c binder: print warnings when detecting oneway spamming. 2020-09-03 18:24:41 +02:00
binder_alloc.c drivers/android: remove redundant ret variable 2022-02-04 15:40:44 +01:00
binder_alloc.h binder: tell userspace to dump current backtrace when detected oneway spamming 2021-04-10 10:52:04 +02:00
binder_internal.h selinux/stable-5.16 PR 20211101 2021-11-01 21:06:18 -07:00
binder_trace.h binder: add trace at free transaction. 2020-11-11 08:20:44 +01:00
binder.c binder: Gracefully handle BINDER_TYPE_FDA objects with num_fds=0 2022-04-22 17:22:51 +02:00
binderfs.c binderfs: add support for feature files 2021-07-21 13:46:36 +02:00
Kconfig treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00