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* Merge tag 'char-misc-4.15-rc1' of ↵Linus Torvalds2017-11-161-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc updates from Greg KH: "Here is the big set of char/misc and other driver subsystem patches for 4.15-rc1. There are small changes all over here, hyperv driver updates, pcmcia driver updates, w1 driver updats, vme driver updates, nvmem driver updates, and lots of other little one-off driver updates as well. The shortlog has the full details. All of these have been in linux-next for quite a while with no reported issues" * tag 'char-misc-4.15-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (90 commits) VME: Return -EBUSY when DMA list in use w1: keep balance of mutex locks and refcnts MAINTAINERS: Update VME subsystem tree. nvmem: sunxi-sid: add support for A64/H5's SID controller nvmem: imx-ocotp: Update module description nvmem: imx-ocotp: Enable i.MX7D OTP write support nvmem: imx-ocotp: Add i.MX7D timing write clock setup support nvmem: imx-ocotp: Move i.MX6 write clock setup to dedicated function nvmem: imx-ocotp: Add support for banked OTP addressing nvmem: imx-ocotp: Pass parameters via a struct nvmem: imx-ocotp: Restrict OTP write to IMX6 processors nvmem: uniphier: add UniPhier eFuse driver dt-bindings: nvmem: add description for UniPhier eFuse nvmem: set nvmem->owner to nvmem->dev->driver->owner if unset nvmem: qfprom: fix different address space warnings of sparse nvmem: mtk-efuse: fix different address space warnings of sparse nvmem: mtk-efuse: use stack for nvmem_config instead of malloc'ing it nvmem: imx-iim: use stack for nvmem_config instead of malloc'ing it thunderbolt: tb: fix use after free in tb_activate_pcie_devices MAINTAINERS: Add git tree for Thunderbolt development ...
| * Merge 4.14-rc6 into char-misc-nextGreg Kroah-Hartman2017-10-231-10/+1
| |\ | | | | | | | | | | | | | | | | | | We want the driver fixes in here and this resolves a merge issue with the binder driver. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | binder: pr_err() strings should end with newlinesArvind Yadav2017-10-201-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | pr_err() messages should terminated with a new-line to avoid other messages being concatenated onto the end. Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | | Merge tag 'modules-for-v4.15' of ↵Linus Torvalds2017-11-151-1/+1
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux Pull module updates from Jessica Yu: "Summary of modules changes for the 4.15 merge window: - treewide module_param_call() cleanup, fix up set/get function prototype mismatches, from Kees Cook - minor code cleanups" * tag 'modules-for-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: module: Do not paper over type mismatches in module_param_call() treewide: Fix function prototypes for module_param_call() module: Prepare to convert all module_param_call() prototypes kernel/module: Delete an error message for a failed memory allocation in add_module_usage()
| * | treewide: Fix function prototypes for module_param_call()Kees Cook2017-10-311-1/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Several function prototypes for the set/get functions defined by module_param_call() have a slightly wrong argument types. This fixes those in an effort to clean up the calls when running under type-enforced compiler instrumentation for CFI. This is the result of running the following semantic patch: @match_module_param_call_function@ declarer name module_param_call; identifier _name, _set_func, _get_func; expression _arg, _mode; @@ module_param_call(_name, _set_func, _get_func, _arg, _mode); @fix_set_prototype depends on match_module_param_call_function@ identifier match_module_param_call_function._set_func; identifier _val, _param; type _val_type, _param_type; @@ int _set_func( -_val_type _val +const char * _val , -_param_type _param +const struct kernel_param * _param ) { ... } @fix_get_prototype depends on match_module_param_call_function@ identifier match_module_param_call_function._get_func; identifier _val, _param; type _val_type, _param_type; @@ int _get_func( -_val_type _val +char * _val , -_param_type _param +const struct kernel_param * _param ) { ... } Two additional by-hand changes are included for places where the above Coccinelle script didn't notice them: drivers/platform/x86/thinkpad_acpi.c fs/lockd/svc.c Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jessica Yu <jeyu@kernel.org>
* / binder: call poll_wait() unconditionally.Martijn Coenen2017-10-201-10/+1
|/ | | | | | | | | | 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>
* binder: fix use-after-free in binder_transaction()Todd Kjos2017-10-041-27/+66
| | | | | | | | | | | | | | | | | | | | 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>
* binder: fix memory corruption in binder_transaction binderXu YiPing2017-09-181-0/+1
| | | | | | | | | | | | | | | 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>
* binder: fix an ret value overrideXu YiPing2017-09-181-1/+0
| | | | | | | | | | | 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>
* android: binder: fix type mismatch warningArnd Bergmann2017-09-181-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* ANDROID: binder: don't queue async transactions to thread.Martijn Coenen2017-09-011-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* ANDROID: binder: don't enqueue death notifications to thread todo.Martijn Coenen2017-09-011-16/+6
| | | | | | | | | | | 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>
* ANDROID: binder: Don't BUG_ON(!spin_is_locked()).Martijn Coenen2017-09-011-16/+10
| | | | | | | | | | | 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>
* ANDROID: binder: Add BINDER_GET_NODE_DEBUG_INFO ioctlColin Cross2017-09-011-0/+43
| | | | | | | | | | | | 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>
* ANDROID: binder: push new transactions to waiting threads.Martijn Coenen2017-09-011-54/+127
| | | | | | | | | | | | | | | 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>
* ANDROID: binder: remove proc waitqueueMartijn Coenen2017-09-011-74/+181
| | | | | | | | | | | | | | | 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>
* android: binder: Add page usage in binder statsSherry Yang2017-09-011-0/+2
| | | | | | | | 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>
* android: binder: Add global lru shrinker to binderSherry Yang2017-08-281-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | 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>
* android: binder: Add allocator selftestSherry Yang2017-08-281-0/+2
| | | | | | | | | | | | | 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>
* binder: fix incorrect cmd to binder_stat_brTodd Kjos2017-08-231-1/+1
| | | | | | | | | | | | | | 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>
* binder: free memory on errorChristian Brauner2017-08-231-2/+6
| | | | | | | | | | 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>
* binder: remove unused BINDER_SMALL_BUF_SIZE defineDmitry Safonov2017-07-171-2/+0
| | | | | | | | | | | 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>
* android: binder: Use dedicated helper to access rlimit valueKrzysztof Opasiak2017-07-171-1/+1
| | | | | | | | 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>
* binder: remove global binder lockTodd Kjos2017-07-171-43/+3
| | | | | | | 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>
* binder: fix death race conditionsMartijn Coenen2017-07-171-32/+32
| | | | | | | | | | | | 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>
* binder: protect against stale pointers in print_binder_transactionTodd Kjos2017-07-171-20/+40
| | | | | | | | | | | 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>
* binder: protect binder_ref with outer lockTodd Kjos2017-07-171-50/+83
| | | | | | | | | | | | | 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>
* binder: use inner lock to protect thread accountingTodd Kjos2017-07-171-5/+23
| | | | | | | | | 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>
* binder: protect transaction_stack with inner lock.Martijn Coenen2017-07-171-17/+79
| | | | | | | | | | | | | 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>
* binder: protect proc->threads with inner_lockTodd Kjos2017-07-171-24/+63
| | | | | | | | | | 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>
* binder: protect proc->nodes with inner lockTodd Kjos2017-07-171-23/+89
| | | | | | | | 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>
* binder: add spinlock to protect binder_nodeTodd Kjos2017-07-171-55/+165
| | | | | | | | | 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>
* binder: add spinlocks to protect todo listsTodd Kjos2017-07-171-86/+269
| | | | | | | | | | | | | | 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>
* binder: use inner lock to sync work dq and node countsTodd Kjos2017-07-171-51/+198
| | | | | | | | | | | | | | | | | | | | 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>
* binder: introduce locking helper functionsTodd Kjos2017-07-171-0/+238
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* binder: use node->tmp_refs to ensure node safetyTodd Kjos2017-07-171-20/+104
| | | | | | | | | | | | 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>
* binder: refactor binder ref inc/dec for thread safetyTodd Kjos2017-07-171-122/+362
| | | | | | | | | | | | | | | | | | | | | | 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>
* binder: make sure accesses to proc/thread are safeTodd Kjos2017-07-171-27/+206
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* binder: make sure target_node has strong refTodd Kjos2017-07-171-5/+17
| | | | | | | | | | 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>
* binder: guarantee txn complete / errors delivered in-orderTodd Kjos2017-07-171-54/+73
| | | | | | | | | | | | | | | 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>
* binder: refactor binder_pop_transactionTodd Kjos2017-07-171-15/+15
| | | | | | | | | | | | 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>
* binder: use atomic for transaction_log indexTodd Kjos2017-07-171-16/+59
| | | | | | | | | | | | | | | | | | 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>
* binder: protect against two threads freeing bufferTodd Kjos2017-07-171-2/+2
| | | | | | | | | 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>
* binder: remove dead code in binder_get_ref_for_nodeTodd Kjos2017-07-171-11/+5
| | | | | | | | node is always non-NULL in binder_get_ref_for_node so the conditional and else clause are not needed Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* binder: don't modify thread->looper from other threadsTodd Kjos2017-07-171-11/+11
| | | | | | | | | | | | | | | The looper member of struct binder_thread is a bitmask of control bits. All of the existing bits are modified by the affected thread except for BINDER_LOOPER_STATE_NEED_RETURN which can be modified in binder_deferred_flush() by another thread. To avoid adding a spinlock around all read-mod-writes to modify a bit, the BINDER_LOOPER_STATE_NEED_RETURN flag is replaced by a separate field in struct binder_thread. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* binder: avoid race conditions when enqueuing txnTodd Kjos2017-07-171-3/+4
| | | | | | | | | | | | | | | | | | | | Currently, the transaction complete work item is queued after the transaction. This means that it is possible for the transaction to be handled and a reply to be enqueued in the current thread before the transaction complete is enqueued, which violates the protocol with userspace who may not expect the transaction complete. Fixed by always enqueing the transaction complete first. Also, once the transaction is enqueued, it is unsafe to access since it might be freed. Currently, t->flags is accessed to determine whether a sync wake is needed. Changed to access tr->flags instead. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* binder: refactor queue management in binder_thread_readTodd Kjos2017-07-171-57/+94
| | | | | | | | | | | | | | | | | | | | | | In binder_thread_read, the BINDER_WORK_NODE command is used to communicate the references on the node to userspace. It can take a couple of iterations in the loop to construct the list of commands for user space. When locking is added, the lock would need to be release on each iteration which means the state could change. The work item is not dequeued during this process which prevents a simpler queue management that can just dequeue up front and handle the work item. Fixed by changing the BINDER_WORK_NODE algorithm in binder_thread_read to determine which commands to send to userspace atomically in 1 pass so it stays consistent with the kernel view. The work item is now dequeued immediately since only 1 pass is needed. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* binder: add log information for binder transaction failuresTodd Kjos2017-07-171-10/+77
| | | | | | | | | | | | | | | Add additional information to determine the cause of binder failures. Adds the following to failed transaction log and kernel messages: return_error : value returned for transaction return_error_param : errno returned by binder allocator return_error_line : line number where error detected Also, return BR_DEAD_REPLY if an allocation error indicates a dead proc (-ESRCH) Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* binder: make binder_last_id an atomicTodd Kjos2017-07-171-4/+4
| | | | | | | Use an atomic for binder_last_id to avoid locking it Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* binder: change binder_stats to atomicsBadhri Jagan Sridharan2017-07-171-20/+28
| | | | | | | | Use atomics for stats to avoid needing to lock for increments/decrements Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>