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alistair23-linux/drivers/android
Jann Horn 8eb52a1ee3 binder: Fix race between mmap() and binder_alloc_print_pages()
binder_alloc_print_pages() iterates over
alloc->pages[0..alloc->buffer_size-1] under alloc->mutex.
binder_alloc_mmap_handler() writes alloc->pages and alloc->buffer_size
without holding that lock, and even writes them before the last bailout
point.

Unfortunately we can't take the alloc->mutex in the ->mmap() handler
because mmap_sem can be taken while alloc->mutex is held.
So instead, we have to locklessly check whether the binder_alloc has been
fully initialized with binder_alloc_get_vma(), like in
binder_alloc_new_buf_locked().

Fixes: 8ef4665aa1 ("android: binder: Add page usage in binder stats")
Cc: stable@vger.kernel.org
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20191018205631.248274-1-jannh@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-14 11:44:46 +08:00
..
Kconfig binder: add functions to copy to/from binder buffers 2019-02-12 10:43:57 +01:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
binder.c Merge 5.4-rc5 into char-misc-next 2019-10-27 18:48:33 +01:00
binder_alloc.c binder: Fix race between mmap() and binder_alloc_print_pages() 2019-11-14 11:44:46 +08:00
binder_alloc.h binder: return errors from buffer copy functions 2019-07-01 08:42:47 +02:00
binder_alloc_selftest.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282 2019-06-05 17:36:37 +02:00
binder_internal.h binder: prevent UAF read in print_binder_transaction_log_entry() 2019-10-10 14:39:22 +02:00
binder_trace.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282 2019-06-05 17:36:37 +02:00
binderfs.c binder: Add binder_proc logging to binderfs 2019-09-04 13:31:26 +02:00