aboutsummaryrefslogtreecommitdiff
path: root/drivers/android/binder.c
AgeCommit message (Collapse)AuthorFilesLines
2017-11-28the rest of drivers/*: annotate ->poll() instancesAl Viro1-1/+1
Signed-off-by: Al Viro <[email protected]>
2017-11-28ANDROID: binder: fix transaction leak.Martijn Coenen1-9/+31
If a call to put_user() fails, we failed to properly free a transaction and send a failed reply (if necessary). Signed-off-by: Martijn Coenen <[email protected]> Cc: stable <[email protected]> # 4.14 Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-11-28ANDROID: binder: Add thread->process_todo flag.Martijn Coenen1-44/+107
This flag determines whether the thread should currently process the work in the thread->todo worklist. The prime usecase for this is improving the performance of synchronous transactions: all synchronous transactions post a BR_TRANSACTION_COMPLETE to the calling thread, but there's no reason to return that command to userspace right away - userspace anyway needs to wait for the reply. Likewise, a synchronous transaction that contains a binder object can cause a BC_ACQUIRE/BC_INCREFS to be returned to userspace; since the caller must anyway hold a strong/weak ref for the duration of the call, postponing these commands until the reply comes in is not a problem. Note that this flag is not used to determine whether a thread can handle process work; a thread should never pick up process work when thread work is still pending. Before patch: ------------------------------------------------------------------ Benchmark Time CPU Iterations ------------------------------------------------------------------ BM_sendVec_binderize/4 45959 ns 20288 ns 34351 BM_sendVec_binderize/8 45603 ns 20080 ns 34909 BM_sendVec_binderize/16 45528 ns 20113 ns 34863 BM_sendVec_binderize/32 45551 ns 20122 ns 34881 BM_sendVec_binderize/64 45701 ns 20183 ns 34864 BM_sendVec_binderize/128 45824 ns 20250 ns 34576 BM_sendVec_binderize/256 45695 ns 20171 ns 34759 BM_sendVec_binderize/512 45743 ns 20211 ns 34489 BM_sendVec_binderize/1024 46169 ns 20430 ns 34081 After patch: ------------------------------------------------------------------ Benchmark Time CPU Iterations ------------------------------------------------------------------ BM_sendVec_binderize/4 42939 ns 17262 ns 40653 BM_sendVec_binderize/8 42823 ns 17243 ns 40671 BM_sendVec_binderize/16 42898 ns 17243 ns 40594 BM_sendVec_binderize/32 42838 ns 17267 ns 40527 BM_sendVec_binderize/64 42854 ns 17249 ns 40379 BM_sendVec_binderize/128 42881 ns 17288 ns 40427 BM_sendVec_binderize/256 42917 ns 17297 ns 40429 BM_sendVec_binderize/512 43184 ns 17395 ns 40411 BM_sendVec_binderize/1024 43119 ns 17357 ns 40432 Signed-off-by: Martijn Coenen <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-11-16Merge tag 'char-misc-4.15-rc1' of ↵Linus Torvalds1-1/+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 ...
2017-11-15Merge tag 'modules-for-v4.15' of ↵Linus Torvalds1-1/+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()
2017-10-31treewide: Fix function prototypes for module_param_call()Kees Cook1-1/+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 <[email protected]> Signed-off-by: Jessica Yu <[email protected]>
2017-10-23Merge 4.14-rc6 into char-misc-nextGreg Kroah-Hartman1-10/+1
We want the driver fixes in here and this resolves a merge issue with the binder driver. Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-10-20binder: pr_err() strings should end with newlinesArvind Yadav1-1/+1
pr_err() messages should terminated with a new-line to avoid other messages being concatenated onto the end. Signed-off-by: Arvind Yadav <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-10-20binder: call poll_wait() unconditionally.Martijn Coenen1-10/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-10-04binder: fix use-after-free in binder_transaction()Todd Kjos1-27/+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 <[email protected]> Cc: stable <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-09-18binder: fix memory corruption in binder_transaction binderXu YiPing1-0/+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 <[email protected]> Signed-off-by: Todd Kjos <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-09-18binder: fix an ret value overrideXu YiPing1-1/+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 <[email protected]> Signed-off-by: Todd Kjos <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-09-18android: binder: fix type mismatch warningArnd Bergmann1-3/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-09-01ANDROID: binder: don't queue async transactions to thread.Martijn Coenen1-3/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-09-01ANDROID: binder: don't enqueue death notifications to thread todo.Martijn Coenen1-16/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-09-01ANDROID: binder: Don't BUG_ON(!spin_is_locked()).Martijn Coenen1-16/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-09-01ANDROID: binder: Add BINDER_GET_NODE_DEBUG_INFO ioctlColin Cross1-0/+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 <[email protected]> Signed-off-by: Martijn Coenen <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-09-01ANDROID: binder: push new transactions to waiting threads.Martijn Coenen1-54/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-09-01ANDROID: binder: remove proc waitqueueMartijn Coenen1-74/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-09-01android: binder: Add page usage in binder statsSherry Yang1-0/+2
Add the number of active, lru, and free pages for each binder process in binder stats Signed-off-by: Sherry Yang <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-08-28android: binder: Add global lru shrinker to binderSherry Yang1-0/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-08-28android: binder: Add allocator selftestSherry Yang1-0/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-08-22binder: fix incorrect cmd to binder_stat_brTodd Kjos1-1/+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 <[email protected]> Reported-by: Dan Carpenter <[email protected]> Fixes: 26549d177410 ("binder: guarantee txn complete / errors delivered in-order") Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-08-22binder: free memory on errorChristian Brauner1-2/+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 <[email protected]> Cc: stable <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: remove unused BINDER_SMALL_BUF_SIZE defineDmitry Safonov1-2/+0
It was never used since addition of binder to linux mainstream tree. Cc: Greg Kroah-Hartman <[email protected]> Cc: "Arve Hjønnevåg" <[email protected]> Cc: Riley Andrews <[email protected]> Cc: [email protected] Signed-off-by: Dmitry Safonov <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17android: binder: Use dedicated helper to access rlimit valueKrzysztof Opasiak1-1/+1
Use rlimit() helper instead of manually writing whole chain from current task to rlim_cur Signed-off-by: Krzysztof Opasiak <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: remove global binder lockTodd Kjos1-43/+3
Remove global mutex and rely on fine-grained locking Signed-off-by: Todd Kjos <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: fix death race conditionsMartijn Coenen1-32/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: protect against stale pointers in print_binder_transactionTodd Kjos1-20/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: protect binder_ref with outer lockTodd Kjos1-50/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: use inner lock to protect thread accountingTodd Kjos1-5/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: protect transaction_stack with inner lock.Martijn Coenen1-17/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: protect proc->threads with inner_lockTodd Kjos1-24/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: protect proc->nodes with inner lockTodd Kjos1-23/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: add spinlock to protect binder_nodeTodd Kjos1-55/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: add spinlocks to protect todo listsTodd Kjos1-86/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: use inner lock to sync work dq and node countsTodd Kjos1-51/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: introduce locking helper functionsTodd Kjos1-0/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: use node->tmp_refs to ensure node safetyTodd Kjos1-20/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: refactor binder ref inc/dec for thread safetyTodd Kjos1-122/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: make sure accesses to proc/thread are safeTodd Kjos1-27/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: make sure target_node has strong refTodd Kjos1-5/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: guarantee txn complete / errors delivered in-orderTodd Kjos1-54/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: refactor binder_pop_transactionTodd Kjos1-15/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: use atomic for transaction_log indexTodd Kjos1-16/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: protect against two threads freeing bufferTodd Kjos1-2/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: remove dead code in binder_get_ref_for_nodeTodd Kjos1-11/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: don't modify thread->looper from other threadsTodd Kjos1-11/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: avoid race conditions when enqueuing txnTodd Kjos1-3/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-07-17binder: refactor queue management in binder_thread_readTodd Kjos1-57/+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 <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
Powered by cgit, Gruvboxed by Blaster4385.