Carlos Llamas a1d85fc6bd binder: fix hang of unregistered readers ... commit 31643d84b8c3d9c846aa0e20bc033e46c68c7e7d upstream. With the introduction of binder_available_for_proc_work_ilocked() in commit 1b77e9dcc3 ("ANDROID: binder: remove proc waitqueue") a binder thread can only "wait_for_proc_work" after its thread->looper has been marked as BINDER_LOOPER_STATE_{ENTERED|REGISTERED}. This means an unregistered reader risks waiting indefinitely for work since it never gets added to the proc->waiting_threads. If there are no further references to its waitqueue either the task will hang. The same applies to readers using the (e)poll interface. I couldn't find the rationale behind this restriction. So this patch restores the previous behavior of allowing unregistered threads to "wait_for_proc_work". Note that an error message for this scenario, which had previously become unreachable, is now re-enabled. Fixes: 1b77e9dcc3 ("ANDROID: binder: remove proc waitqueue") Cc: stable@vger.kernel.org Cc: Martijn Coenen <maco@google.com> Cc: Arve Hjønnevåg <arve@google.com> Signed-off-by: Carlos Llamas <cmllamas@google.com> Link: https://lore.kernel.org/r/20240711201452.2017543-1-cmllamas@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2024-08-03 08:54:21 +02:00
..
Kconfig	remove CONFIG_ANDROID	2022-07-01 10:41:09 +02:00
Makefile	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
binder.c	binder: fix hang of unregistered readers	2024-08-03 08:54:21 +02:00
binder_alloc.c	binder: fix race between mmput() and do_exit()	2024-01-25 15:35:42 -08:00
binder_alloc.h	binder: fix memory leak in binder_init()	2023-08-04 15:25:01 +02:00
binder_alloc_selftest.c	Revert "android: binder: stop saving a pointer to the VMA"	2023-05-13 20:30:16 +09:00
binder_internal.h	binder: fix max_thread type inconsistency	2024-05-25 16:22:54 +02:00
binder_trace.h	Binder: add TF_UPDATE_TXN to replace outdated txn	2022-06-27 16:16:30 +02:00
binderfs.c	Char/Misc driver changes for 6.6-rc1	2023-09-01 09:53:54 -07:00