user/sven/linux.git/drivers/android/binderfs.c, branch v5.4.3

binder: Add binder_proc logging to binderfs

2019-09-04T11:31:26Z

Currently /sys/kernel/debug/binder/proc contains the debug data for every binder_proc instance. This patch makes this information also available in a binderfs instance mounted with a mount option "stats=global" in addition to debugfs. The patch does not affect the presence of the file in debugfs. If a binderfs instance is mounted at path /dev/binderfs, this file would be present at /dev/binderfs/binder_logs/proc. This change provides an alternate way to access this file when debugfs is not mounted. Acked-by: Christian Brauner Signed-off-by: Hridya Valsaraju Link: https://lore.kernel.org/r/20190903161655.107408-5-hridya@google.com Signed-off-by: Greg Kroah-Hartman

binder: Make transaction_log available in binderfs

2019-09-04T11:31:22Z

Currently, the binder transaction log files 'transaction_log' and 'failed_transaction_log' live in debugfs at the following locations: /sys/kernel/debug/binder/failed_transaction_log /sys/kernel/debug/binder/transaction_log This patch makes these files also available in a binderfs instance mounted with the mount option "stats=global". It does not affect the presence of these files in debugfs. If a binderfs instance is mounted at path /dev/binderfs, the location of these files will be as follows: /dev/binderfs/binder_logs/failed_transaction_log /dev/binderfs/binder_logs/transaction_log This change provides an alternate option to access these files when debugfs is not mounted. Acked-by: Christian Brauner Signed-off-by: Hridya Valsaraju Link: https://lore.kernel.org/r/20190903161655.107408-4-hridya@google.com Signed-off-by: Greg Kroah-Hartman

binder: Add stats, state and transactions files

2019-09-04T11:31:18Z

The following binder stat files currently live in debugfs. /sys/kernel/debug/binder/state /sys/kernel/debug/binder/stats /sys/kernel/debug/binder/transactions This patch makes these files available in a binderfs instance mounted with the mount option 'stats=global'. For example, if a binderfs instance is mounted at path /dev/binderfs, the above files will be available at the following locations: /dev/binderfs/binder_logs/state /dev/binderfs/binder_logs/stats /dev/binderfs/binder_logs/transactions This provides a way to access them even when debugfs is not mounted. Acked-by: Christian Brauner Signed-off-by: Hridya Valsaraju Acked-by: Christian Brauner Link: https://lore.kernel.org/r/20190903161655.107408-3-hridya@google.com Signed-off-by: Greg Kroah-Hartman

binder: add a mount option to show global stats

2019-09-04T11:31:13Z

Currently, all binder state and statistics live in debugfs. We need this information even when debugfs is not mounted. This patch adds the mount option 'stats' to enable a binderfs instance to have binder debug information present in the same. 'stats=global' will enable the global binder statistics. In the future, 'stats=local' will enable binder statistics local to the binderfs instance. The two modes 'global' and 'local' will be mutually exclusive. 'stats=global' option is only available for a binderfs instance mounted in the initial user namespace. An attempt to use the option to mount a binderfs instance in another user namespace will return an EPERM error. Signed-off-by: Hridya Valsaraju Acked-by: Christian Brauner Link: https://lore.kernel.org/r/20190903161655.107408-2-hridya@google.com Signed-off-by: Greg Kroah-Hartman

binder: Add default binder devices through binderfs when configured

2019-09-04T11:17:35Z

Currently, since each binderfs instance needs its own private binder devices, every time a binderfs instance is mounted, all the default binder devices need to be created via the BINDER_CTL_ADD IOCTL. This patch aims to add a solution to automatically create the default binder devices for each binderfs instance that gets mounted. To achieve this goal, when CONFIG_ANDROID_BINDERFS is set, the default binder devices specified by CONFIG_ANDROID_BINDER_DEVICES are created in each binderfs instance instead of global devices being created by the binder driver. Co-developed-by: Christian Brauner Signed-off-by: Christian Brauner Signed-off-by: Hridya Valsaraju Reviewed-by: Joel Fernandes (Google) Link: https://lore.kernel.org/r/20190808222727.132744-2-hridya@google.com Link: https://lore.kernel.org/r/20190904110704.8606-2-christian.brauner@ubuntu.com Signed-off-by: Greg Kroah-Hartman

binder: Validate the default binderfs device names.

2019-09-04T11:17:35Z

Length of a binderfs device name cannot exceed BINDERFS_MAX_NAME. This patch adds a check in binderfs_init() to ensure the same for the default binder devices that will be created in every binderfs instance. Co-developed-by: Christian Brauner Signed-off-by: Christian Brauner Signed-off-by: Hridya Valsaraju Reviewed-by: Joel Fernandes (Google) Link: https://lore.kernel.org/r/20190808222727.132744-3-hridya@google.com Link: https://lore.kernel.org/r/20190904110704.8606-3-christian.brauner@ubuntu.com Signed-off-by: Greg Kroah-Hartman

binderfs: remove separate device_initcall()

2019-02-01T14:50:26Z

binderfs should not have a separate device_initcall(). When a kernel is compiled with CONFIG_ANDROID_BINDERFS register the filesystem alongside CONFIG_ANDROID_IPC. This use-case is especially sensible when users specify CONFIG_ANDROID_IPC=y, CONFIG_ANDROID_BINDERFS=y and ANDROID_BINDER_DEVICES="". When CONFIG_ANDROID_BINDERFS=n then this always succeeds so there's no regression potential for legacy workloads. Signed-off-by: Christian Brauner Signed-off-by: Greg Kroah-Hartman

binderfs: respect limit on binder control creation

2019-01-30T14:23:48Z

We currently adhere to the reserved devices limit when creating new binderfs devices in binderfs instances not located in the inital ipc namespace. But it is still possible to rob the host instances of their 4 reserved devices by creating the maximum allowed number of devices in a single binderfs instance located in a non-initial ipc namespace and then mounting 4 separate binderfs instances in non-initial ipc namespaces. That happens because the limit is currently not respected for the creation of the initial binder-control device node. Block this nonsense by performing the same check in binderfs_binder_ctl_create() that we perform in binderfs_binder_device_create(). Fixes: 36bdf3cae09d ("binderfs: reserve devices for initial mount") Signed-off-by: Christian Brauner Signed-off-by: Greg Kroah-Hartman

binderfs: switch from d_add() to d_instantiate()

2019-01-22T11:25:54Z

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 Signed-off-by: Christian Brauner Signed-off-by: Greg Kroah-Hartman

binderfs: drop lock in binderfs_binder_ctl_create

2019-01-22T11:25:53Z

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 Signed-off-by: Christian Brauner Signed-off-by: Greg Kroah-Hartman