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2019-01-22binderfs: switch from d_add() to d_instantiate()Christian Brauner
In a previous commit we switched from a d_alloc_name() + d_lookup() combination to setup a new dentry and find potential duplicates to the more idiomatic lookup_one_len(). As far as I understand, this also means we need to switch from d_add() to d_instantiate() since lookup_one_len() will create a new dentry when it doesn't find an existing one and add the new dentry to the hash queues. So we only need to call d_instantiate() to connect the dentry to the inode and turn it into a positive dentry. If we were to use d_add() we sure see stack traces like the following indicating that adding the same dentry twice over the same inode: [ 744.441889] CPU: 4 PID: 2849 Comm: landscape-sysin Not tainted 5.0.0-rc1-brauner-binderfs #243 [ 744.441889] Hardware name: Dell DCS XS24-SC2 /XS24-SC2 , BIOS S59_3C20 04/07/2011 [ 744.441889] RIP: 0010:__d_lookup_rcu+0x76/0x190 [ 744.441889] Code: 89 75 c0 49 c1 e9 20 49 89 fd 45 89 ce 41 83 e6 07 42 8d 04 f5 00 00 00 00 89 45 c8 eb 0c 48 8b 1b 48 85 db 0f 84 81 00 00 00 <44> 8b 63 fc 4c 3b 6b 10 75 ea 48 83 7b 08 00 74 e3 41 83 e4 fe 41 [ 744.441889] RSP: 0018:ffffb8c984e27ad0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 [ 744.441889] RAX: 0000000000000038 RBX: ffff9407ef770c08 RCX: ffffb8c980011000 [ 744.441889] RDX: ffffb8c984e27b54 RSI: ffffb8c984e27ce0 RDI: ffff9407e6689600 [ 744.441889] RBP: ffffb8c984e27b28 R08: ffffb8c984e27ba4 R09: 0000000000000007 [ 744.441889] R10: ffff9407e5c4f05c R11: 973f3eb9d84a94e5 R12: 0000000000000002 [ 744.441889] R13: ffff9407e6689600 R14: 0000000000000007 R15: 00000007bfef7a13 [ 744.441889] FS: 00007f0db13bb740(0000) GS:ffff9407f3b00000(0000) knlGS:0000000000000000 [ 744.441889] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 744.441889] CR2: 00007f0dacc51024 CR3: 000000032961a000 CR4: 00000000000006e0 [ 744.441889] Call Trace: [ 744.441889] lookup_fast+0x53/0x300 [ 744.441889] walk_component+0x49/0x350 [ 744.441889] ? inode_permission+0x63/0x1a0 [ 744.441889] link_path_walk.part.33+0x1bc/0x5a0 [ 744.441889] ? path_init+0x190/0x310 [ 744.441889] path_lookupat+0x95/0x210 [ 744.441889] filename_lookup+0xb6/0x190 [ 744.441889] ? __check_object_size+0xb8/0x1b0 [ 744.441889] ? strncpy_from_user+0x50/0x1a0 [ 744.441889] user_path_at_empty+0x36/0x40 [ 744.441889] ? user_path_at_empty+0x36/0x40 [ 744.441889] vfs_statx+0x76/0xe0 [ 744.441889] __do_sys_newstat+0x3d/0x70 [ 744.441889] __x64_sys_newstat+0x16/0x20 [ 744.441889] do_syscall_64+0x5a/0x120 [ 744.441889] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 744.441889] RIP: 0033:0x7f0db0ec2775 [ 744.441889] Code: 00 00 00 75 05 48 83 c4 18 c3 e8 26 55 02 00 66 0f 1f 44 00 00 83 ff 01 48 89 f0 77 30 48 89 c7 48 89 d6 b8 04 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 03 f3 c3 90 48 8b 15 e1 b6 2d 00 f7 d8 64 89 [ 744.441889] RSP: 002b:00007ffc36bc9388 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 [ 744.441889] RAX: ffffffffffffffda RBX: 00007ffc36bc9300 RCX: 00007f0db0ec2775 [ 744.441889] RDX: 00007ffc36bc9400 RSI: 00007ffc36bc9400 RDI: 00007f0dad26f050 [ 744.441889] RBP: 0000000000c0bc60 R08: 0000000000000000 R09: 0000000000000001 [ 744.441889] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc36bc9400 [ 744.441889] R13: 0000000000000001 R14: 00000000ffffff9c R15: 0000000000c0bc60 Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Christian Brauner <christian@brauner.io> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-22binderfs: drop lock in binderfs_binder_ctl_createChristian Brauner
The binderfs_binder_ctl_create() call is a no-op on subsequent calls and the first call is done before we unlock the suberblock. Hence, there is no need to take inode_lock() in there. Let's remove it. Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Christian Brauner <christian@brauner.io> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-22binderfs: kill_litter_super() before cleanupChristian Brauner
Al pointed out that first calling kill_litter_super() before cleaning up info is more correct since destroying info doesn't depend on the state of the dentries and inodes. That the opposite remains true is not guaranteed. Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Christian Brauner <christian@brauner.io> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-22binderfs: rework binderfs_binder_device_create()Christian Brauner
- switch from d_alloc_name() + d_lookup() to lookup_one_len(): Instead of using d_alloc_name() and then doing a d_lookup() with the allocated dentry to find whether a device with the name we're trying to create already exists switch to using lookup_one_len(). The latter will either return the existing dentry or a new one. - switch from kmalloc() + strscpy() to kmemdup(): Use a more idiomatic way to copy the name for the new dentry that userspace gave us. Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Christian Brauner <christian@brauner.io> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-22binderfs: rework binderfs_fill_super()Christian Brauner
Al pointed out that on binderfs_fill_super() error deactivate_locked_super() will call binderfs_kill_super() so all of the freeing and putting we currently do in binderfs_fill_super() is unnecessary and buggy. Let's simply return errors and let binderfs_fill_super() take care of cleaning up on error. Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Christian Brauner <christian@brauner.io> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-22binderfs: prevent renaming the control dentryChristian Brauner
- make binderfs control dentry immutable: We don't allow to unlink it since it is crucial for binderfs to be useable but if we allow to rename it we make the unlink trivial to bypass. So prevent renaming too and simply treat the control dentry as immutable. - add is_binderfs_control_device() helper: Take the opportunity and turn the check for the control dentry into a separate helper is_binderfs_control_device() since it's now used in two places. - simplify binderfs_rename(): Instead of hand-rolling our custom version of simple_rename() just dumb the whole function down to first check whether we're trying to rename the control dentry. If we do EPERM the caller and if not call simple_rename(). Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Christian Brauner <christian@brauner.io> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-22binderfs: remove outdated commentChristian Brauner
The comment stems from an early version of that patchset and is just confusing now. Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Christian Brauner <christian@brauner.io> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-18binderfs: fix error return code in binderfs_fill_super()Wei Yongjun
Fix to return a negative error code -ENOMEM from the new_inode() and d_make_root() error handling cases instead of 0, as done elsewhere in this function. Fixes: 849d540ddfcd ("binderfs: implement "max" mount option") Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Reviewed-by: Christian Brauner <christian@brauner.io> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-12binderfs: handle !CONFIG_IPC_NS buildsChristian Brauner
kbuild reported a build faile in [1]. This is triggered when CONFIG_IPC_NS is not set. So let's make the use of init_ipc_ns conditional on CONFIG_IPC_NS being set. [1]: https://lists.01.org/pipermail/kbuild-all/2019-January/056903.html Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-11binderfs: reserve devices for initial mountChristian Brauner
The binderfs instance in the initial ipc namespace will always have a reserve of 4 binder devices unless explicitly capped by specifying a lower value via the "max" mount option. This ensures when binder devices are removed (on accident or on purpose) they can always be recreated without risking that all minor numbers have already been used up. Cc: Todd Kjos <tkjos@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-11binderfs: rename header to binderfs.hChristian Brauner
It doesn't make sense to call the header binder_ctl.h when its sole existence is tied to binderfs. So give it a sensible name. Users will far more easily remember binderfs.h than binder_ctl.h. Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-11binderfs: implement "max" mount optionChristian Brauner
Since binderfs can be mounted by userns root in non-initial user namespaces some precautions are in order. First, a way to set a maximum on the number of binder devices that can be allocated per binderfs instance and second, a way to reserve a reasonable chunk of binderfs devices for the initial ipc namespace. A first approach as seen in [1] used sysctls similiar to devpts but was shown to be flawed (cf. [2] and [3]) since some aspects were unneeded. This is an alternative approach which avoids sysctls completely and instead switches to a single mount option. Starting with this commit binderfs instances can be mounted with a limit on the number of binder devices that can be allocated. The max=<count> mount option serves as a per-instance limit. If max=<count> is set then only <count> number of binder devices can be allocated in this binderfs instance. This allows to safely bind-mount binderfs instances into unprivileged user namespaces since userns root in a non-initial user namespace cannot change the mount option as long as it does not own the mount namespace the binderfs mount was created in and hence cannot drain the host of minor device numbers [1]: https://lore.kernel.org/lkml/20181221133909.18794-1-christian@brauner.io/ [2]; https://lore.kernel.org/lkml/20181221163316.GA8517@kroah.com/ [3]: https://lore.kernel.org/lkml/CAHRSSEx+gDVW4fKKK8oZNAir9G5icJLyodO8hykv3O0O1jt2FQ@mail.gmail.com/ [4]: https://lore.kernel.org/lkml/20181221192044.5yvfnuri7gdop4rs@brauner.io/ Cc: Todd Kjos <tkjos@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-08binderfs: make each binderfs mount a new instanceChristian Brauner
When currently mounting binderfs in the same ipc namespace twice: mount -t binder binder /A mount -t binder binder /B then the binderfs instances mounted on /A and /B will be the same, i.e. they will have the same superblock. This was the first approach that seemed reasonable. However, this leads to some problems and inconsistencies: /* private binderfs instance in same ipc namespace */ There is no way for a user to request a private binderfs instance in the same ipc namespace. This request has been made in a private mail to me by two independent people. /* bind-mounts */ If users want the same binderfs instance to appear in multiple places they can use bind mounts. So there is no value in having a request for a new binderfs mount giving them the same instance. /* unexpected behavior */ It's surprising that request to mount binderfs is not giving the user a new instance like tmpfs, devpts, ramfs, and others do. /* past mistakes */ Other pseudo-filesystems once made the same mistakes of giving back the same superblock when actually requesting a new mount (cf. devpts's deprecated "newinstance" option). We should not make the same mistake. Once we've committed to always giving back the same superblock in the same IPC namespace with the next kernel release we will not be able to make that change so better to do it now. /* kdbusfs */ It was pointed out to me that kdbusfs - which is conceptually closely related to binderfs - also allowed users to get a private kdbusfs instance in the same IPC namespace by making each mount of kdbusfs a separate instance. I think that makes a lot of sense. Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-08binderfs: remove wrong kern_mount() callChristian Brauner
The binderfs filesystem never needs to be mounted by the kernel itself. This is conceptually wrong and should never have been done in the first place. Fixes: 3ad20fe393b ("binder: implement binderfs") Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-19binder: implement binderfsChristian Brauner
As discussed at Linux Plumbers Conference 2018 in Vancouver [1] this is the implementation of binderfs. /* Abstract */ binderfs is a backwards-compatible filesystem for Android's binder ipc mechanism. Each ipc namespace will mount a new binderfs instance. Mounting binderfs multiple times at different locations in the same ipc namespace will not cause a new super block to be allocated and hence it will be the same filesystem instance. Each new binderfs mount will have its own set of binder devices only visible in the ipc namespace it has been mounted in. All devices in a new binderfs mount will follow the scheme binder%d and numbering will always start at 0. /* Backwards compatibility */ Devices requested in the Kconfig via CONFIG_ANDROID_BINDER_DEVICES for the initial ipc namespace will work as before. They will be registered via misc_register() and appear in the devtmpfs mount. Specifically, the standard devices binder, hwbinder, and vndbinder will all appear in their standard locations in /dev. Mounting or unmounting the binderfs mount in the initial ipc namespace will have no effect on these devices, i.e. they will neither show up in the binderfs mount nor will they disappear when the binderfs mount is gone. /* binder-control */ Each new binderfs instance comes with a binder-control device. No other devices will be present at first. The binder-control device can be used to dynamically allocate binder devices. All requests operate on the binderfs mount the binder-control device resides in. Assuming a new instance of binderfs has been mounted at /dev/binderfs via mount -t binderfs binderfs /dev/binderfs. Then a request to create a new binder device can be made as illustrated in [2]. Binderfs devices can simply be removed via unlink(). /* Implementation details */ - dynamic major number allocation: When binderfs is registered as a new filesystem it will dynamically allocate a new major number. The allocated major number will be returned in struct binderfs_device when a new binder device is allocated. - global minor number tracking: Minor are tracked in a global idr struct that is capped at BINDERFS_MAX_MINOR. The minor number tracker is protected by a global mutex. This is the only point of contention between binderfs mounts. - struct binderfs_info: Each binderfs super block has its own struct binderfs_info that tracks specific details about a binderfs instance: - ipc namespace - dentry of the binder-control device - root uid and root gid of the user namespace the binderfs instance was mounted in - mountable by user namespace root: binderfs can be mounted by user namespace root in a non-initial user namespace. The devices will be owned by user namespace root. - binderfs binder devices without misc infrastructure: New binder devices associated with a binderfs mount do not use the full misc_register() infrastructure. The misc_register() infrastructure can only create new devices in the host's devtmpfs mount. binderfs does however only make devices appear under its own mountpoint and thus allocates new character device nodes from the inode of the root dentry of the super block. This will have the side-effect that binderfs specific device nodes do not appear in sysfs. This behavior is similar to devpts allocated pts devices and has no effect on the functionality of the ipc mechanism itself. [1]: https://goo.gl/JL2tfX [2]: program to allocate a new binderfs binder device: #define _GNU_SOURCE #include <errno.h> #include <fcntl.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/ioctl.h> #include <sys/stat.h> #include <sys/types.h> #include <unistd.h> #include <linux/android/binder_ctl.h> int main(int argc, char *argv[]) { int fd, ret, saved_errno; size_t len; struct binderfs_device device = { 0 }; if (argc < 2) exit(EXIT_FAILURE); len = strlen(argv[1]); if (len > BINDERFS_MAX_NAME) exit(EXIT_FAILURE); memcpy(device.name, argv[1], len); fd = open("/dev/binderfs/binder-control", O_RDONLY | O_CLOEXEC); if (fd < 0) { printf("%s - Failed to open binder-control device\n", strerror(errno)); exit(EXIT_FAILURE); } ret = ioctl(fd, BINDER_CTL_ADD, &device); saved_errno = errno; close(fd); errno = saved_errno; if (ret < 0) { printf("%s - Failed to allocate new binder device\n", strerror(errno)); exit(EXIT_FAILURE); } printf("Allocated new binder device with major %d, minor %d, and " "name %s\n", device.major, device.minor, device.name); exit(EXIT_SUCCESS); } Cc: Martijn Coenen <maco@android.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Acked-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-19binder: fix use-after-free due to ksys_close() during fdget()Todd Kjos
44d8047f1d8 ("binder: use standard functions to allocate fds") exposed a pre-existing issue in the binder driver. fdget() is used in ksys_ioctl() as a performance optimization. One of the rules associated with fdget() is that ksys_close() must not be called between the fdget() and the fdput(). There is a case where this requirement is not met in the binder driver which results in the reference count dropping to 0 when the device is still in use. This can result in use-after-free or other issues. If userpace has passed a file-descriptor for the binder driver using a BINDER_TYPE_FDA object, then kys_close() is called on it when handling a binder_ioctl(BC_FREE_BUFFER) command. This violates the assumptions for using fdget(). The problem is fixed by deferring the close using task_work_add(). A new variant of __close_fd() was created that returns a struct file with a reference. The fput() is deferred instead of using ksys_close(). Fixes: 44d8047f1d87a ("binder: use standard functions to allocate fds") Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Todd Kjos <tkjos@google.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-06binder: filter out nodes when showing binder procsTodd Kjos
When dumping out binder transactions via a debug node, the output is too verbose if a process has many nodes. Change the output for transaction dumps to only display nodes with pending async transactions. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-06binder: fix kerneldoc header for struct binder_bufferTodd Kjos
Fix the incomplete kerneldoc header for struct binder_buffer. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-06binder: remove BINDER_DEBUG_ENTRY()Yangtao Li
We already have the DEFINE_SHOW_ATTRIBUTE.There is no need to define such a macro,so remove BINDER_DEBUG_ENTRY. Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> Acked-by: Todd Kjos <tkjos@android.com> Reviewed-by: Joey Pabalinas <joeypabalinas@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-03Merge 4.20-rc5 into char-misc-nextGreg Kroah-Hartman
We need the fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-26binder: fix sparse warnings on locking contextTodd Kjos
Add __acquire()/__release() annnotations to fix warnings in sparse context checking There is one case where the warning was due to a lack of a "default:" case in a switch statement where a lock was being released in each of the cases, so the default case was added. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-26binder: fix race that allows malicious free of live bufferTodd Kjos
Malicious code can attempt to free buffers using the BC_FREE_BUFFER ioctl to binder. There are protections against a user freeing a buffer while in use by the kernel, however there was a window where BC_FREE_BUFFER could be used to free a recently allocated buffer that was not completely initialized. This resulted in a use-after-free detected by KASAN with a malicious test program. This window is closed by setting the buffer's allow_user_free attribute to 0 when the buffer is allocated or when the user has previously freed it instead of waiting for the caller to set it. The problem was that when the struct buffer was recycled, allow_user_free was stale and set to 1 allowing a free to go through. Signed-off-by: Todd Kjos <tkjos@google.com> Acked-by: Arve Hjønnevåg <arve@android.com> Cc: stable <stable@vger.kernel.org> # 4.14 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02binder: make symbol 'binder_free_buf' staticWei Yongjun
Fixes the following sparse warning: drivers/android/binder.c:3312:1: warning: symbol 'binder_free_buf' was not declared. Should it be static? Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-16Merge b4.19-rc4 into char-misc-nextGreg Kroah-Hartman
We want the bugfixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-14binder: Add BINDER_GET_NODE_INFO_FOR_REF ioctl.Martijn Coenen
This allows the context manager to retrieve information about nodes that it holds a reference to, such as the current number of references to those nodes. Such information can for example be used to determine whether the servicemanager is the only process holding a reference to a node. This information can then be passed on to the process holding the node, which can in turn decide whether it wants to shut down to reduce resource usage. Signed-off-by: Martijn Coenen <maco@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-14android: binder: use kstrdup instead of open-coding itRasmus Villemoes
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-14binder: use standard functions to allocate fdsTodd Kjos
Binder uses internal fs interfaces to allocate and install fds: __alloc_fd __fd_install __close_fd get_files_struct put_files_struct These were used to support the passing of fds between processes as part of a transaction. The actual allocation and installation of the fds in the target process was handled by the sending process so the standard functions, alloc_fd() and fd_install() which assume task==current couldn't be used. This patch refactors this mechanism so that the fds are allocated and installed by the target process allowing the standard functions to be used. The sender now creates a list of fd fixups that contains the struct *file and the address to fixup with the new fd once it is allocated. This list is processed by the target process when the transaction is dequeued. A new error case is introduced by this change. If an async transaction with file descriptors cannot allocate new fds in the target (probably due to out of file descriptors), the transaction is discarded with a log message. In the old implementation this would have been detected in the sender context and failed prior to sending. Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-14android: binder: no outgoing transaction when thread todo has transactionSherry Yang
When a process dies, failed reply is sent to the sender of any transaction queued on a dead thread's todo list. The sender asserts that the received failed reply corresponds to the head of the transaction stack. This assert can fail if the dead thread is allowed to send outgoing transactions when there is already a transaction on its todo list, because this new transaction can end up on the transaction stack of the original sender. The following steps illustrate how this assertion can fail. 1. Thread1 sends txn19 to Thread2 (T1->transaction_stack=txn19, T2->todo+=txn19) 2. Without processing todo list, Thread2 sends txn20 to Thread1 (T1->todo+=txn20, T2->transaction_stack=txn20) 3. T1 processes txn20 on its todo list (T1->transaction_stack=txn20->txn19, T1->todo=<empty>) 4. T2 dies, T2->todo cleanup attempts to send failed reply for txn19, but T1->transaction_stack points to txn20 -- assertion failes Step 2. is the incorrect behavior. When there is a transaction on a thread's todo list, this thread should not be able to send any outgoing synchronous transactions. Only the head of the todo list needs to be checked because only threads that are waiting for proc work can directly receive work from another thread, and no work is allowed to be queued on such a thread without waking up the thread. This patch also enforces that a thread is not waiting for proc work when a work is directly enqueued to its todo list. Acked-by: Arve Hjønnevåg <arve@android.com> Signed-off-by: Sherry Yang <sherryy@android.com> Reviewed-by: Martijn Coenen <maco@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-12android: binder: fix the race mmap and alloc_new_buf_lockedMinchan Kim
There is RaceFuzzer report like below because we have no lock to close below the race between binder_mmap and binder_alloc_new_buf_locked. To close the race, let's use memory barrier so that if someone see alloc->vma is not NULL, alloc->vma_vm_mm should be never NULL. (I didn't add stable mark intentionallybecause standard android userspace libraries that interact with binder (libbinder & libhwbinder) prevent the mmap/ioctl race. - from Todd) " Thread interleaving: CPU0 (binder_alloc_mmap_handler) CPU1 (binder_alloc_new_buf_locked) ===== ===== // drivers/android/binder_alloc.c // #L718 (v4.18-rc3) alloc->vma = vma; // drivers/android/binder_alloc.c // #L346 (v4.18-rc3) if (alloc->vma == NULL) { ... // alloc->vma is not NULL at this point return ERR_PTR(-ESRCH); } ... // #L438 binder_update_page_range(alloc, 0, (void *)PAGE_ALIGN((uintptr_t)buffer->data), end_page_addr); // In binder_update_page_range() #L218 // But still alloc->vma_vm_mm is NULL here if (need_mm && mmget_not_zero(alloc->vma_vm_mm)) alloc->vma_vm_mm = vma->vm_mm; Crash Log: ================================================================== BUG: KASAN: null-ptr-deref in __atomic_add_unless include/asm-generic/atomic-instrumented.h:89 [inline] BUG: KASAN: null-ptr-deref in atomic_add_unless include/linux/atomic.h:533 [inline] BUG: KASAN: null-ptr-deref in mmget_not_zero include/linux/sched/mm.h:75 [inline] BUG: KASAN: null-ptr-deref in binder_update_page_range+0xece/0x18e0 drivers/android/binder_alloc.c:218 Write of size 4 at addr 0000000000000058 by task syz-executor0/11184 CPU: 1 PID: 11184 Comm: syz-executor0 Not tainted 4.18.0-rc3 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.2-0-g33fbe13 by qemu-project.org 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x16e/0x22c lib/dump_stack.c:113 kasan_report_error mm/kasan/report.c:352 [inline] kasan_report+0x163/0x380 mm/kasan/report.c:412 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x140/0x1a0 mm/kasan/kasan.c:267 kasan_check_write+0x14/0x20 mm/kasan/kasan.c:278 __atomic_add_unless include/asm-generic/atomic-instrumented.h:89 [inline] atomic_add_unless include/linux/atomic.h:533 [inline] mmget_not_zero include/linux/sched/mm.h:75 [inline] binder_update_page_range+0xece/0x18e0 drivers/android/binder_alloc.c:218 binder_alloc_new_buf_locked drivers/android/binder_alloc.c:443 [inline] binder_alloc_new_buf+0x467/0xc30 drivers/android/binder_alloc.c:513 binder_transaction+0x125b/0x4fb0 drivers/android/binder.c:2957 binder_thread_write+0xc08/0x2770 drivers/android/binder.c:3528 binder_ioctl_write_read.isra.39+0x24f/0x8e0 drivers/android/binder.c:4456 binder_ioctl+0xa86/0xf34 drivers/android/binder.c:4596 vfs_ioctl fs/ioctl.c:46 [inline] do_vfs_ioctl+0x154/0xd40 fs/ioctl.c:686 ksys_ioctl+0x94/0xb0 fs/ioctl.c:701 __do_sys_ioctl fs/ioctl.c:708 [inline] __se_sys_ioctl fs/ioctl.c:706 [inline] __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:706 do_syscall_64+0x167/0x4b0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe " Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Martijn Coenen <maco@android.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-08android: binder: Rate-limit debug and userspace triggered err msgsSherry Yang
Use rate-limited debug messages where userspace can trigger excessive log spams. Acked-by: Arve Hjønnevåg <arve@android.com> Signed-off-by: Sherry Yang <sherryy@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-02android: binder: Show extra_buffers_size in traceSherry Yang
Add extra_buffers_size to the binder_transaction_alloc_buf tracepoint. Acked-by: Arve Hjønnevåg <arve@android.com> Signed-off-by: Sherry Yang <sherryy@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-24android: binder: Include asm/cacheflush.h after linux/ include filesGuenter Roeck
If asm/cacheflush.h is included first, the following build warnings are seen with sparc32 builds. In file included from arch/sparc/include/asm/cacheflush.h:11:0, from drivers/android/binder.c:54: arch/sparc/include/asm/cacheflush_32.h:40:37: warning: 'struct page' declared inside parameter list will not be visible outside of this definition or declaration Moving the asm/ include after linux/ includes solves the problem. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-24android: binder_alloc: Include asm/cacheflush.h after linux/ include filesGuenter Roeck
If asm/cacheflush.h is included first, the following build warnings are seen with sparc32 builds. In file included from ./arch/sparc/include/asm/cacheflush.h:11:0, from drivers/android/binder_alloc.c:20: ./arch/sparc/include/asm/cacheflush_32.h:40:37: warning: 'struct page' declared inside parameter list Moving the asm/ include after linux/ includes fixes the problem. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-07android: binder: Drop dependency on !M68KGeert Uytterhoeven
As of commit 7124330dabe5b3cb ("m68k/uaccess: Revive 64-bit get_user()"), the 64-bit Android binder interface builds fine on m68k. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-12treewide: kzalloc() -> kcalloc()Kees Cook
The kzalloc() function has a 2-factor argument form, kcalloc(). This patch replaces cases of: kzalloc(a * b, gfp) with: kcalloc(a * b, gfp) as well as handling cases of: kzalloc(a * b * c, gfp) with: kzalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kzalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kzalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(char) * COUNT + COUNT , ...) | kzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc + kcalloc ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kzalloc(C1 * C2 * C3, ...) | kzalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kzalloc(sizeof(THING) * C2, ...) | kzalloc(sizeof(TYPE) * C2, ...) | kzalloc(C1 * C2 * C3, ...) | kzalloc(C1 * C2, ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - (E1) * E2 + E1, E2 , ...) | - kzalloc + kcalloc ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc + kcalloc ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-05-14android: binder: Change return type to vm_fault_tSouptick Joarder
Use new return type vm_fault_t for fault handler in struct vm_operations_struct. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. Reference id -> 1c8f422059ae ("mm: change return type to vm_fault_t") Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14ANDROID: binder: change down_write to down_readMinchan Kim
binder_update_page_range needs down_write of mmap_sem because vm_insert_page need to change vma->vm_flags to VM_MIXEDMAP unless it is set. However, when I profile binder working, it seems every binder buffers should be mapped in advance by binder_mmap. It means we could set VM_MIXEDMAP in binder_mmap time which is already hold a mmap_sem as down_write so binder_update_page_range doesn't need to hold a mmap_sem as down_write. Please use proper API down_read. It would help mmap_sem contention problem as well as fixing down_write abuse. Ganesh Mahendran tested app launching and binder throughput test and he said he couldn't find any problem and I did binder latency test per Greg KH request(Thanks Martijn to teach me how I can do) I cannot find any problem, too. Cc: Ganesh Mahendran <opensource.ganesh@gmail.com> Cc: Joe Perches <joe@perches.com> Cc: Arve Hjønnevåg <arve@android.com> Cc: Todd Kjos <tkjos@google.com> Reviewed-by: Martijn Coenen <maco@android.com> Signed-off-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14ANDROID: binder: correct the cmd print for BINDER_WORK_RETURN_ERROR宋金时
When to execute binder_stat_br the e->cmd has been modifying as BR_OK instead of the original return error cmd, in fact we want to know the original return error, such as BR_DEAD_REPLY or BR_FAILED_REPLY, etc. instead of always BR_OK, in order to avoid the value of the e->cmd is always BR_OK, so we need assign the value of the e->cmd to cmd before e->cmd = BR_OK. Signed-off-by: songjinshi <songjinshi@xiaomi.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14ANDROID: binder: remove 32-bit binder interface.Martijn Coenen
New devices launching with Android P need to use the 64-bit binder interface, even on 32-bit SoCs [0]. This change removes the Kconfig option to select the 32-bit binder interface. We don't think this will affect existing userspace for the following reasons: 1) The latest Android common tree is 4.14, so we don't believe any Android devices are on kernels >4.14. 2) Android devices launch on an LTS release and stick with it, so we wouldn't expect devices running on <= 4.14 now to upgrade to 4.17 or later. But even if they did, they'd rebuild the world (kernel + userspace) anyway. 3) Other userspaces like 'anbox' are already using the 64-bit interface. Note that this change doesn't remove the 32-bit UAPI itself; the reason for that is that Android userspace always uses the latest UAPI headers from upstream, and userspace retains 32-bit support for devices that are upgrading. This will be removed as well in 2-3 years, at which point we can remove the code from the UAPI as well. Finally, this change introduces build errors on archs where 64-bit get_user/put_user is not supported, so make binder unavailable on m68k (which wouldn't want it anyway). [0]: https://android-review.googlesource.com/c/platform/build/+/595193 Signed-off-by: Martijn Coenen <maco@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-30Merge 4.17-rc3 into char-misc-nextGreg Kroah-Hartman
We want the fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-23ANDROID: binder: re-order some conditionsDan Carpenter
It doesn't make any difference to runtime but I've switched these two checks to make my static checker happy. The problem is that "buffer->data_size" is user controlled and if it's less than "sizeo(*hdr)" then that means "offset" can be more than "buffer->data_size". It's just cleaner to check it in the other order. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Martijn Coenen <maco@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-23ANDROID: binder: prevent transactions into own process.Martijn Coenen
This can't happen with normal nodes (because you can't get a ref to a node you own), but it could happen with the context manager; to make the behavior consistent with regular nodes, reject transactions into the context manager by the process owning it. Reported-by: syzbot+09e05aba06723a94d43d@syzkaller.appspotmail.com Signed-off-by: Martijn Coenen <maco@android.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-16ANDROID: binder: synchronize_rcu() when using POLLFREE.Martijn Coenen
To prevent races with ep_remove_waitqueue() removing the waitqueue at the same time. Reported-by: syzbot+a2a3c4909716e271487e@syzkaller.appspotmail.com Signed-off-by: Martijn Coenen <maco@android.com> Cc: stable <stable@vger.kernel.org> # 4.14+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-16binder: replace "%p" with "%pK"Todd Kjos
The format specifier "%p" can leak kernel addresses. Use "%pK" instead. There were 4 remaining cases in binder.c. Signed-off-by: Todd Kjos <tkjos@google.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-16ANDROID: binder: remove WARN() for redundant txn errorTodd Kjos
binder_send_failed_reply() is called when a synchronous transaction fails. It reports an error to the thread that is waiting for the completion. Given that the transaction is synchronous, there should never be more than 1 error response to that thread -- this was being asserted with a WARN(). However, when exercising the driver with syzbot tests, cases were observed where multiple "synchronous" requests were sent without waiting for responses, so it is possible that multiple errors would be reported to the thread. This testing was conducted with panic_on_warn set which forced the crash. This is easily reproduced by sending back-to-back "synchronous" transactions without checking for any response (eg, set read_size to 0): bwr.write_buffer = (uintptr_t)&bc1; bwr.write_size = sizeof(bc1); bwr.read_buffer = (uintptr_t)&br; bwr.read_size = 0; ioctl(fd, BINDER_WRITE_READ, &bwr); sleep(1); bwr2.write_buffer = (uintptr_t)&bc2; bwr2.write_size = sizeof(bc2); bwr2.read_buffer = (uintptr_t)&br; bwr2.read_size = 0; ioctl(fd, BINDER_WRITE_READ, &bwr2); sleep(1); The first transaction is sent to the servicemanager and the reply fails because no VMA is set up by this client. After binder_send_failed_reply() is called, the BINDER_WORK_RETURN_ERROR is sitting on the thread's todo list since the read_size was 0 and the client is not waiting for a response. The 2nd transaction is sent and the BINDER_WORK_RETURN_ERROR has not been consumed, so the thread's reply_error.cmd is still set (normally cleared when the BINDER_WORK_RETURN_ERROR is handled). Therefore when the servicemanager attempts to reply to the 2nd failed transaction, the error is already set and it triggers this warning. This is a user error since it is not waiting for the synchronous transaction to complete. If it ever does check, it will see an error. Changed the WARN() to a pr_warn(). Signed-off-by: Todd Kjos <tkjos@android.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-16binder: check for binder_thread allocation failure in binder_poll()Eric Biggers
If the kzalloc() in binder_get_thread() fails, binder_poll() dereferences the resulting NULL pointer. Fix it by returning POLLERR if the memory allocation failed. This bug was found by syzkaller using fault injection. Reported-by: syzbot <syzkaller@googlegroups.com> Fixes: 457b9a6f09f0 ("Staging: android: add binder driver") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-11vfs: do bulk POLL* -> EPOLL* replacementLinus Torvalds
This is the mindless scripted replacement of kernel use of POLL* variables as described by Al, done by this script: for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'` for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done done with de-mangling cleanups yet to come. NOTE! On almost all architectures, the EPOLL* constants have the same values as the POLL* constants do. But they keyword here is "almost". For various bad reasons they aren't the same, and epoll() doesn't actually work quite correctly in some cases due to this on Sparc et al. The next patch from Al will sort out the final differences, and we should be all done. Scripted-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-01Merge tag 'char-misc-4.16-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver updates from Greg KH: "Here is the big pull request for char/misc drivers for 4.16-rc1. There's a lot of stuff in here. Three new driver subsystems were added for various types of hardware busses: - siox - slimbus - soundwire as well as a new vboxguest subsystem for the VirtualBox hypervisor drivers. There's also big updates from the FPGA subsystem, lots of Android binder fixes, the usual handful of hyper-v updates, and lots of other smaller driver updates. All of these have been in linux-next for a long time, with no reported issues" * tag 'char-misc-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (155 commits) char: lp: use true or false for boolean values android: binder: use VM_ALLOC to get vm area android: binder: Use true and false for boolean values lkdtm: fix handle_irq_event symbol for INT_HW_IRQ_EN EISA: Delete error message for a failed memory allocation in eisa_probe() EISA: Whitespace cleanup misc: remove AVR32 dependencies virt: vbox: Add error mapping for VERR_INVALID_NAME and VERR_NO_MORE_FILES soundwire: Fix a signedness bug uio_hv_generic: fix new type mismatch warnings uio_hv_generic: fix type mismatch warnings auxdisplay: img-ascii-lcd: add missing MODULE_DESCRIPTION/AUTHOR/LICENSE uio_hv_generic: add rescind support uio_hv_generic: check that host supports monitor page uio_hv_generic: create send and receive buffers uio: document uio_hv_generic regions doc: fix documentation about uio_hv_generic vmbus: add monitor_id and subchannel_id to sysfs per channel vmbus: fix ABI documentation uio_hv_generic: use ISR callback method ...
2018-01-30Merge branch 'misc.poll' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull poll annotations from Al Viro: "This introduces a __bitwise type for POLL### bitmap, and propagates the annotations through the tree. Most of that stuff is as simple as 'make ->poll() instances return __poll_t and do the same to local variables used to hold the future return value'. Some of the obvious brainos found in process are fixed (e.g. POLLIN misspelled as POLL_IN). At that point the amount of sparse warnings is low and most of them are for genuine bugs - e.g. ->poll() instance deciding to return -EINVAL instead of a bitmap. I hadn't touched those in this series - it's large enough as it is. Another problem it has caught was eventpoll() ABI mess; select.c and eventpoll.c assumed that corresponding POLL### and EPOLL### were equal. That's true for some, but not all of them - EPOLL### are arch-independent, but POLL### are not. The last commit in this series separates userland POLL### values from the (now arch-independent) kernel-side ones, converting between them in the few places where they are copied to/from userland. AFAICS, this is the least disruptive fix preserving poll(2) ABI and making epoll() work on all architectures. As it is, it's simply broken on sparc - try to give it EPOLLWRNORM and it will trigger only on what would've triggered EPOLLWRBAND on other architectures. EPOLLWRBAND and EPOLLRDHUP, OTOH, are never triggered at all on sparc. With this patch they should work consistently on all architectures" * 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (37 commits) make kernel-side POLL... arch-independent eventpoll: no need to mask the result of epi_item_poll() again eventpoll: constify struct epoll_event pointers debugging printk in sg_poll() uses %x to print POLL... bitmap annotate poll(2) guts 9p: untangle ->poll() mess ->si_band gets POLL... bitmap stored into a user-visible long field ring_buffer_poll_wait() return value used as return value of ->poll() the rest of drivers/*: annotate ->poll() instances media: annotate ->poll() instances fs: annotate ->poll() instances ipc, kernel, mm: annotate ->poll() instances net: annotate ->poll() instances apparmor: annotate ->poll() instances tomoyo: annotate ->poll() instances sound: annotate ->poll() instances acpi: annotate ->poll() instances crypto: annotate ->poll() instances block: annotate ->poll() instances x86: annotate ->poll() instances ...
2018-01-25android: binder: use VM_ALLOC to get vm areaGanesh Mahendran
VM_IOREMAP is used to access hardware through a mechanism called I/O mapped memory. Android binder is a IPC machanism which will not access I/O memory. And VM_IOREMAP has alignment requiement which may not needed in binder. __get_vm_area_node() { ... if (flags & VM_IOREMAP) align = 1ul << clamp_t(int, fls_long(size), PAGE_SHIFT, IOREMAP_MAX_ORDER); ... } This patch will save some kernel vm area, especially for 32bit os. In 32bit OS, kernel vm area is only 240MB. We may got below error when launching a app: <3>[ 4482.440053] binder_alloc: binder_alloc_mmap_handler: 15728 8ce67000-8cf65000 get_vm_area failed -12 <3>[ 4483.218817] binder_alloc: binder_alloc_mmap_handler: 15745 8ce67000-8cf65000 get_vm_area failed -12 Signed-off-by: Ganesh Mahendran <opensource.ganesh@gmail.com> Acked-by: Martijn Coenen <maco@android.com> Acked-by: Todd Kjos <tkjos@google.com> Cc: stable <stable@vger.kernel.org> ---- V3: update comments V2: update comments Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>