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2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-21android: binder: Fix null ptr dereference in debug msgSherry Yang
Don't access next->data in kernel debug message when the next buffer is null. Acked-by: Arve Hjønnevåg <arve@android.com> Signed-off-by: Sherry Yang <sherryy@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-21android: binder: Don't get mm from taskSherry Yang
Use binder_alloc struct's mm_struct rather than getting a reference to the mm struct through get_task_mm to avoid a potential deadlock between lru lock, task lock and dentry lock, since a thread can be holding the task lock and the dentry lock while trying to acquire the lru lock. Acked-by: Arve Hjønnevåg <arve@android.com> Signed-off-by: Sherry Yang <sherryy@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-20binder: call poll_wait() unconditionally.Martijn Coenen
Because we're not guaranteed that subsequent calls to poll() will have a poll_table_struct parameter with _qproc set. When _qproc is not set, poll_wait() is a noop, and we won't be woken up correctly. Signed-off-by: Martijn Coenen <maco@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-15Merge tag 'char-misc-4.14-rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver fixes from Greg KH: "Here are 4 patches to resolve some char/misc driver issues found these past weeks. One of them is a mei bugfix and another is a new mei device id. There is also a hyper-v fix for a reported issue, and a binder issue fix for a problem reported by a few people. All of these have been in my tree for a while, I don't know if linux-next is really testing much this month. But 0-day is happy with them :)" * tag 'char-misc-4.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: binder: fix use-after-free in binder_transaction() Drivers: hv: vmbus: Fix bugs in rescind handling mei: me: add gemini lake devices id mei: always use domain runtime pm callbacks.
2017-10-04binder: fix use-after-free in binder_transaction()Todd Kjos
User-space normally keeps the node alive when creating a transaction since it has a reference to the target. The local strong ref keeps it alive if the sending process dies before the target process processes the transaction. If the source process is malicious or has a reference counting bug, this can fail. In this case, when we attempt to decrement the node in the failure path, the node has already been freed. This is fixed by taking a tmpref on the node while constructing the transaction. To avoid re-acquiring the node lock and inner proc lock to increment the proc's tmpref, a helper is used that does the ref increments on both the node and proc. Signed-off-by: Todd Kjos <tkjos@google.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-03android: binder: drop lru lock in isolate callbackSherry Yang
Drop the global lru lock in isolate callback before calling zap_page_range which calls cond_resched, and re-acquire the global lru lock before returning. Also change return code to LRU_REMOVED_RETRY. Use mmput_async when fail to acquire mmap sem in an atomic context. Fix "BUG: sleeping function called from invalid context" errors when CONFIG_DEBUG_ATOMIC_SLEEP is enabled. Also restore mmput_async, which was initially introduced in commit ec8d7c14ea14 ("mm, oom_reaper: do not mmput synchronously from the oom reaper context"), and was removed in commit 212925802454 ("mm: oom: let oom_reap_task and exit_mmap run concurrently"). Link: http://lkml.kernel.org/r/20170914182231.90908-1-sherryy@android.com Fixes: f2517eb76f1f2 ("android: binder: Add global lru shrinker to binder") Signed-off-by: Sherry Yang <sherryy@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reported-by: Kyle Yan <kyan@codeaurora.org> Acked-by: Arve Hjønnevåg <arve@android.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Martijn Coenen <maco@google.com> Cc: Todd Kjos <tkjos@google.com> Cc: Riley Andrews <riandrews@android.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Hillf Danton <hdanton@sina.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Hoeun Ryu <hoeun.ryu@gmail.com> Cc: Christopher Lameter <cl@linux.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-18binder: fix memory corruption in binder_transaction binderXu YiPing
commit 7a4408c6bd3e ("binder: make sure accesses to proc/thread are safe") made a change to enqueue tcomplete to thread->todo before enqueuing the transaction. However, in err_dead_proc_or_thread case, the tcomplete is directly freed, without dequeued. It may cause the thread->todo list to be corrupted. So, dequeue it before freeing. Fixes: 7a4408c6bd3e ("binder: make sure accesses to proc/thread are safe") Signed-off-by: Xu YiPing <xuyiping@hisilicon.com> Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-18binder: fix an ret value overrideXu YiPing
commit 372e3147df70 ("binder: guarantee txn complete / errors delivered in-order") incorrectly defined a local ret value. This ret value will be invalid when out of the if block Fixes: 372e3147df70 ("binder: refactor binder ref inc/dec for thread safety") Signed-off-by: Xu YiPing <xuyiping@hislicon.com> Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-18android: binder: fix type mismatch warningArnd Bergmann
Allowing binder to expose the 64-bit API on 32-bit kernels caused a build warning: drivers/android/binder.c: In function 'binder_transaction_buffer_release': drivers/android/binder.c:2220:15: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast] fd_array = (u32 *)(parent_buffer + fda->parent_offset); ^ drivers/android/binder.c: In function 'binder_translate_fd_array': drivers/android/binder.c:2445:13: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast] fd_array = (u32 *)(parent_buffer + fda->parent_offset); ^ drivers/android/binder.c: In function 'binder_fixup_parent': drivers/android/binder.c:2511:18: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast] This adds extra type casts to avoid the warning. However, there is another problem with the Kconfig option: turning it on or off creates two incompatible ABI versions, a kernel that has this enabled cannot run user space that was built without it or vice versa. A better solution might be to leave the option hidden until the binder code is fixed to deal with both ABI versions. Fixes: e8d2ed7db7c3 ("Revert "staging: Fix build issues with new binder API"") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-01ANDROID: binder: don't queue async transactions to thread.Martijn Coenen
This can cause issues with processes using the poll() interface: 1) client sends two oneway transactions 2) the second one gets queued on async_todo (because the server didn't handle the first one yet) 3) server returns from poll(), picks up the first transaction and does transaction work 4) server is done with the transaction, sends BC_FREE_BUFFER, and the second transaction gets moved to thread->todo 5) libbinder's handlePolledCommands() only handles the commands in the current data buffer, so doesn't see the new transaction 6) the server continues running and issues a new outgoing transaction. Now, it suddenly finds the incoming oneway transaction on its thread todo, and returns that to userspace. 7) userspace does not expect this to happen; it may be holding a lock while making the outgoing transaction, and if handling the incoming trasnaction requires taking the same lock, userspace will deadlock. By queueing the async transaction to the proc workqueue, we make sure it's only picked up when a thread is ready for proc work. Signed-off-by: Martijn Coenen <maco@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-01ANDROID: binder: don't enqueue death notifications to thread todo.Martijn Coenen
This allows userspace to request death notifications without having to worry about getting an immediate callback on the same thread; one scenario where this would be problematic is if the death recipient handler grabs a lock that was already taken earlier (eg as part of a nested transaction). Signed-off-by: Martijn Coenen <maco@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-01ANDROID: binder: Don't BUG_ON(!spin_is_locked()).Martijn Coenen
Because is_spin_locked() always returns false on UP systems. Use assert_spin_locked() instead, and remove the WARN_ON() instances, since those were easy to verify. Signed-off-by: Martijn Coenen <maco@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-01ANDROID: binder: Add BINDER_GET_NODE_DEBUG_INFO ioctlColin Cross
The BINDER_GET_NODE_DEBUG_INFO ioctl will return debug info on a node. Each successive call reusing the previous return value will return the next node. The data will be used by libmemunreachable to mark the pointers with kernel references as reachable. Signed-off-by: Colin Cross <ccross@android.com> Signed-off-by: Martijn Coenen <maco@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-01ANDROID: binder: push new transactions to waiting threads.Martijn Coenen
Instead of pushing new transactions to the process waitqueue, select a thread that is waiting on proc work to handle the transaction. This will make it easier to improve priority inheritance in future patches, by setting the priority before we wake up a thread. If we can't find a waiting thread, submit the work to the proc waitqueue instead as we did previously. Signed-off-by: Martijn Coenen <maco@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-01ANDROID: binder: remove proc waitqueueMartijn Coenen
Removes the process waitqueue, so that threads can only wait on the thread waitqueue. Whenever there is process work to do, pick a thread and wake it up. Having the caller pick a thread is helpful for things like priority inheritance. This also fixes an issue with using epoll(), since we no longer have to block on different waitqueues. Signed-off-by: Martijn Coenen <maco@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-01android: binder: Add page usage in binder statsSherry Yang
Add the number of active, lru, and free pages for each binder process in binder stats Signed-off-by: Sherry Yang <sherryy@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-01android: binder: fixup crash introduced by moving buffer hdrSherry Yang
Fix crash introduced by 74310e06be4d74dcf67cd108366710dee5c576d5 (android: binder: Move buffer out of area shared with user space) when close is called after open without mmap in between. Reported-by: kernel test robot <fengguang.wu@intel.com> Fixes: 74310e06be4d ("android: binder: Move buffer out of area shared with user space") Signed-off-by: Sherry Yang <sherryy@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28android: binder: Add shrinker tracepointsSherry Yang
Add tracepoints in binder transaction allocator to record lru hits and alloc/free page. Signed-off-by: Sherry Yang <sherryy@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28android: binder: Add global lru shrinker to binderSherry Yang
Hold on to the pages allocated and mapped for transaction buffers until the system is under memory pressure. When that happens, use linux shrinker to free pages. Without using shrinker, patch "android: binder: Move buffer out of area shared with user space" will cause a significant slow down for small transactions that fit into the first page because free list buffer header used to be inlined with buffer data. In addition to prevent the performance regression for small transactions, this patch improves the performance for transactions that take up more than one page. Modify alloc selftest to work with the shrinker change. Test: Run memory intensive applications (Chrome and Camera) to trigger shrinker callbacks. Binder frees memory as expected. Test: Run binderThroughputTest with high memory pressure option enabled. Signed-off-by: Sherry Yang <sherryy@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28android: binder: Move buffer out of area shared with user spaceSherry Yang
Binder driver allocates buffer meta data in a region that is mapped in user space. These meta data contain pointers in the kernel. This patch allocates buffer meta data on the kernel heap that is not mapped in user space, and uses a pointer to refer to the data mapped. Signed-off-by: Sherry Yang <sherryy@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28android: binder: Add allocator selftestSherry Yang
binder_alloc_selftest tests that alloc_new_buf handles page allocation and deallocation properly when allocate and free buffers. The test allocates 5 buffers of various sizes to cover all possible page alignment cases, and frees the buffers using a list of exhaustive freeing order. Test: boot the device with ANDROID_BINDER_IPC_SELFTEST config option enabled. Allocator selftest passes. Signed-off-by: Sherry Yang <sherryy@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28android: binder: Refactor prev and next buffer into a helper functionSherry Yang
Use helper functions buffer_next and buffer_prev instead of list_entry to get the next and previous buffers. Signed-off-by: Sherry Yang <sherryy@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28Revert "staging: Fix build issues with new binder API"Jisheng Zhang
This reverts commit d0bdff0db809 ("staging: Fix build issues with new binder API"), because commit e38361d032f1 ("ARM: 8091/2: add get_user() support for 8 byte types") has added the 64bit __get_user_asm_* implementation. Signed-off-by: Jisheng Zhang <jszhang@marvell.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-22binder: fix incorrect cmd to binder_stat_brTodd Kjos
commit 26549d177410 ("binder: guarantee txn complete / errors delivered in-order") passed the locally declared and undefined cmd to binder_stat_br() which results in a bogus cmd field in a trace event and BR stats are incremented incorrectly. Change to use e->cmd which has been initialized. Signed-off-by: Todd Kjos <tkjos@google.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Fixes: 26549d177410 ("binder: guarantee txn complete / errors delivered in-order") Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-22binder: free memory on errorChristian Brauner
On binder_init() the devices string is duplicated and smashed into individual device names which are passed along. However, the original duplicated string wasn't freed in case binder_init() failed. Let's free it on error. Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-22ANDROID: binder: add hwbinder,vndbinder to BINDER_DEVICES.Martijn Coenen
These will be required going forward. Signed-off-by: Martijn Coenen <maco@android.com> Cc: stable <stable@vger.kernel.org> # 4.11+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: remove unused BINDER_SMALL_BUF_SIZE defineDmitry Safonov
It was never used since addition of binder to linux mainstream tree. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Arve Hjønnevåg" <arve@android.com> Cc: Riley Andrews <riandrews@android.com> Cc: devel@driverdev.osuosl.org Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17android: binder: Use dedicated helper to access rlimit valueKrzysztof Opasiak
Use rlimit() helper instead of manually writing whole chain from current task to rlim_cur Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: remove global binder lockTodd Kjos
Remove global mutex and rely on fine-grained locking Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: fix death race conditionsMartijn Coenen
A race existed where one thread could register a death notification for a node, while another thread was cleaning up that node and sending out death notifications for its references, causing simultaneous access to ref->death because different locks were held. Signed-off-by: Martijn Coenen <maco@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: protect against stale pointers in print_binder_transactionTodd Kjos
When printing transactions there were several race conditions that could cause a stale pointer to be deferenced. Fixed by reading the pointer once and using it if valid (which is safe). The transaction buffer also needed protection via proc lock, so it is only printed if we are holding the correct lock. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: protect binder_ref with outer lockTodd Kjos
Use proc->outer_lock to protect the binder_ref structure. The outer lock allows functions operating on the binder_ref to do nested acquires of node and inner locks as necessary to attach refs to nodes atomically. Binder refs must never be accesssed without holding the outer lock. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: use inner lock to protect thread accountingTodd Kjos
Use the inner lock to protect thread accounting fields in proc structure: max_threads, requested_threads, requested_threads_started and ready_threads. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: protect transaction_stack with inner lock.Martijn Coenen
This makes future changes to priority inheritance easier, since we want to be able to look at a thread's transaction stack when selecting a thread to inherit priority for. It also allows us to take just a single lock in a few paths, where we used to take two in succession. Signed-off-by: Martijn Coenen <maco@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: protect proc->threads with inner_lockTodd Kjos
proc->threads will need to be accessed with higher locks of other processes held so use proc->inner_lock to protect it. proc->tmp_ref now needs to be protected by proc->inner_lock. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: protect proc->nodes with inner lockTodd Kjos
When locks for binder_ref handling are added, proc->nodes will need to be modified while holding the outer lock Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: add spinlock to protect binder_nodeTodd Kjos
node->node_lock is used to protect elements of node. No need to acquire for fields that are invariant: debug_id, ptr, cookie. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: add spinlocks to protect todo listsTodd Kjos
The todo lists in the proc, thread, and node structures are accessed by other procs/threads to place work items on the queue. The todo lists are protected by the new proc->inner_lock. No locks should ever be nested under these locks. As the name suggests, an outer lock will be introduced in a later patch. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: use inner lock to sync work dq and node countsTodd Kjos
For correct behavior we need to hold the inner lock when dequeuing and processing node work in binder_thread_read. We now hold the inner lock when we enter the switch statement and release it after processing anything that might be affected by other threads. We also need to hold the inner lock to protect the node weak/strong ref tracking fields as long as node->proc is non-NULL (if it is NULL then we are guaranteed that we don't have any node work queued). This means that other functions that manipulate these fields must hold the inner lock. Refactored these functions to use the inner lock. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: introduce locking helper functionsTodd Kjos
There are 3 main spinlocks which must be acquired in this order: 1) proc->outer_lock : protects most fields of binder_proc, binder_thread, and binder_ref structures. binder_proc_lock() and binder_proc_unlock() are used to acq/rel. 2) node->lock : protects most fields of binder_node. binder_node_lock() and binder_node_unlock() are used to acq/rel 3) proc->inner_lock : protects the thread and node lists (proc->threads, proc->nodes) and all todo lists associated with the binder_proc (proc->todo, thread->todo, proc->delivered_death and node->async_todo). binder_inner_proc_lock() and binder_inner_proc_unlock() are used to acq/rel Any lock under procA must never be nested under any lock at the same level or below on procB. Functions that require a lock held on entry indicate which lock in the suffix of the function name: foo_olocked() : requires node->outer_lock foo_nlocked() : requires node->lock foo_ilocked() : requires proc->inner_lock foo_iolocked(): requires proc->outer_lock and proc->inner_lock foo_nilocked(): requires node->lock and proc->inner_lock Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: use node->tmp_refs to ensure node safetyTodd Kjos
When obtaining a node via binder_get_node(), binder_get_node_from_ref() or binder_new_node(), increment node->tmp_refs to take a temporary reference on the node to ensure the node persists while being used. binder_put_node() must be called to remove the temporary reference. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: refactor binder ref inc/dec for thread safetyTodd Kjos
Once locks are added, binder_ref's will only be accessed safely with the proc lock held. Refactor the inc/dec paths to make them atomic with the binder_get_ref* paths and node inc/dec. For example, instead of: ref = binder_get_ref(proc, handle, strong); ... binder_dec_ref(ref, strong); we now have: ret = binder_dec_ref_for_handle(proc, handle, strong, &rdata); Since the actual ref is no longer exposed to callers, a new struct binder_ref_data is introduced which can be used to return a copy of ref state. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: make sure accesses to proc/thread are safeTodd Kjos
binder_thread and binder_proc may be accessed by other threads when processing transaction. Therefore they must be prevented from being freed while a transaction is in progress that references them. This is done by introducing a temporary reference counter for threads and procs that indicates that the object is in use and must not be freed. binder_thread_dec_tmpref() and binder_proc_dec_tmpref() are used to decrement the temporary reference. It is safe to free a binder_thread if there is no reference and it has been released (indicated by thread->is_dead). It is safe to free a binder_proc if it has no remaining threads and no reference. A spinlock is added to the binder_transaction to safely access and set references for t->from and for debug code to safely access t->to_thread and t->to_proc. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: make sure target_node has strong refTodd Kjos
When initiating a transaction, the target_node must have a strong ref on it. Then we take a second strong ref to make sure the node survives until the transaction is complete. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: guarantee txn complete / errors delivered in-orderTodd Kjos
Since errors are tracked in the return_error/return_error2 fields of the binder_thread object and BR_TRANSACTION_COMPLETEs can be tracked either in those fields or via the thread todo work list, it is possible for errors to be reported ahead of the associated txn complete. Use the thread todo work list for errors to guarantee order. Also changed binder_send_failed_reply to pop the transaction even if it failed to send a reply. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: refactor binder_pop_transactionTodd Kjos
binder_pop_transaction needs to be split into 2 pieces to to allow the proc lock to be held on entry to dequeue the transaction stack, but no lock when kfree'ing the transaction. Split into binder_pop_transaction_locked and binder_free_transaction (the actual locks are still to be added). Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: use atomic for transaction_log indexTodd Kjos
The log->next index for the transaction log was not protected when incremented. This led to a case where log->next++ resulted in an index larger than ARRAY_SIZE(log->entry) and eventually a bad access to memory. Fixed by making the log index an atomic64 and converting to an array by using "% ARRAY_SIZE(log->entry)" Also added "complete" field to the log entry which is written last to tell the print code whether the entry is complete Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: add more debug info when allocation fails.Martijn Coenen
Display information about allocated/free space whenever binder buffer allocation fails on synchronous transactions. Signed-off-by: Martijn Coenen <maco@android.com> Signed-off-by: Siqi Lin <siqilin@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17binder: protect against two threads freeing bufferTodd Kjos
Adds protection against malicious user code freeing the same buffer at the same time which could cause a crash. Cannot happen under normal use. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>