user/sven/linux.git, branch v4.9.20

Linux 4.9.20

2017-03-31T08:32:02Z

usb: musb: fix possible spinlock deadlock

2017-03-31T08:31:46Z

commit bc1e2154542071e3cfe1734b143af9b8bdacf8bd upstream. The DSPS glue calls del_timer_sync() in its musb_platform_disable() implementation, which requires the caller to not hold a lock. But musb_remove() calls musb_platform_disable() will musb->lock held. This could causes spinlock deadlock. So change musb_remove() to call musb_platform_disable() without holds musb->lock. This doesn't impact the musb_platform_disable implementation in other glue drivers. root@am335x-evm:~# modprobe -r musb-dsps [ 126.134879] musb-hdrc musb-hdrc.1: remove, state 1 [ 126.140465] usb usb2: USB disconnect, device number 1 [ 126.146178] usb 2-1: USB disconnect, device number 2 [ 126.416985] musb-hdrc musb-hdrc.1: USB bus 2 deregistered [ 126.423943] [ 126.425525] ====================================================== [ 126.431997] [ INFO: possible circular locking dependency detected ] [ 126.438564] 4.11.0-rc1-00003-g1557f13bca04-dirty #77 Not tainted [ 126.444852] ------------------------------------------------------- [ 126.451414] modprobe/778 is trying to acquire lock: [ 126.456523] (((&glue->timer))){+.-...}, at: [] del_timer_sync+0x0/0xd0 [ 126.464403] [ 126.464403] but task is already holding lock: [ 126.470511] (&(&musb->lock)->rlock){-.-...}, at: [] musb_remove+0x50/0x1 30 [musb_hdrc] [ 126.479965] [ 126.479965] which lock already depends on the new lock. [ 126.479965] [ 126.488531] [ 126.488531] the existing dependency chain (in reverse order) is: [ 126.496368] [ 126.496368] -> #1 (&(&musb->lock)->rlock){-.-...}: [ 126.502968] otg_timer+0x80/0xec [musb_dsps] [ 126.507990] call_timer_fn+0xb4/0x390 [ 126.512372] expire_timers+0xf0/0x1fc [ 126.516754] run_timer_softirq+0x80/0x178 [ 126.521511] __do_softirq+0xc4/0x554 [ 126.525802] irq_exit+0xe8/0x158 [ 126.529735] __handle_domain_irq+0x58/0xb8 [ 126.534583] __irq_usr+0x54/0x80 [ 126.538507] [ 126.538507] -> #0 (((&glue->timer))){+.-...}: [ 126.544636] del_timer_sync+0x40/0xd0 [ 126.549066] musb_remove+0x6c/0x130 [musb_hdrc] [ 126.554370] platform_drv_remove+0x24/0x3c [ 126.559206] device_release_driver_internal+0x14c/0x1e0 [ 126.565225] bus_remove_device+0xd8/0x108 [ 126.569970] device_del+0x1e4/0x308 [ 126.574170] platform_device_del+0x24/0x8c [ 126.579006] platform_device_unregister+0xc/0x20 [ 126.584394] dsps_remove+0x14/0x30 [musb_dsps] [ 126.589595] platform_drv_remove+0x24/0x3c [ 126.594432] device_release_driver_internal+0x14c/0x1e0 [ 126.600450] driver_detach+0x38/0x6c [ 126.604740] bus_remove_driver+0x4c/0xa0 [ 126.609407] SyS_delete_module+0x11c/0x1e4 [ 126.614252] __sys_trace_return+0x0/0x10 Fixes: ea2f35c01d5ea ("usb: musb: Fix sleeping function called from invalid context for hdrc glue") Acked-by: Tony Lindgren Signed-off-by: Bin Liu Signed-off-by: Greg Kroah-Hartman

sched/rt: Add a missing rescheduling point

2017-03-31T08:31:46Z

commit 619bd4a71874a8fd78eb6ccf9f272c5e98bcc7b7 upstream. Since the change in commit: fd7a4bed1835 ("sched, rt: Convert switched_{from, to}_rt() / prio_changed_rt() to balance callbacks") ... we don't reschedule a task under certain circumstances: Lets say task-A, SCHED_OTHER, is running on CPU0 (and it may run only on CPU0) and holds a PI lock. This task is removed from the CPU because it used up its time slice and another SCHED_OTHER task is running. Task-B on CPU1 runs at RT priority and asks for the lock owned by task-A. This results in a priority boost for task-A. Task-B goes to sleep until the lock has been made available. Task-A is already runnable (but not active), so it receives no wake up. The reality now is that task-A gets on the CPU once the scheduler decides to remove the current task despite the fact that a high priority task is enqueued and waiting. This may take a long time. The desired behaviour is that CPU0 immediately reschedules after the priority boost which made task-A the task with the lowest priority. Suggested-by: Peter Zijlstra Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Mike Galbraith Cc: Thomas Gleixner Fixes: fd7a4bed1835 ("sched, rt: Convert switched_{from, to}_rt() prio_changed_rt() to balance callbacks") Link: http://lkml.kernel.org/r/20170124144006.29821-1-bigeasy@linutronix.de Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

fscrypt: remove broken support for detecting keyring key revocation

2017-03-31T08:31:46Z

commit 1b53cf9815bb4744958d41f3795d5d5a1d365e2d upstream. Filesystem encryption ostensibly supported revoking a keyring key that had been used to "unlock" encrypted files, causing those files to become "locked" again. This was, however, buggy for several reasons, the most severe of which was that when key revocation happened to be detected for an inode, its fscrypt_info was immediately freed, even while other threads could be using it for encryption or decryption concurrently. This could be exploited to crash the kernel or worse. This patch fixes the use-after-free by removing the code which detects the keyring key having been revoked, invalidated, or expired. Instead, an encrypted inode that is "unlocked" now simply remains unlocked until it is evicted from memory. Note that this is no worse than the case for block device-level encryption, e.g. dm-crypt, and it still remains possible for a privileged user to evict unused pages, inodes, and dentries by running 'sync; echo 3 > /proc/sys/vm/drop_caches', or by simply unmounting the filesystem. In fact, one of those actions was already needed anyway for key revocation to work even somewhat sanely. This change is not expected to break any applications. In the future I'd like to implement a real API for fscrypt key revocation that interacts sanely with ongoing filesystem operations --- waiting for existing operations to complete and blocking new operations, and invalidating and sanitizing key material and plaintext from the VFS caches. But this is a hard problem, and for now this bug must be fixed. This bug affected almost all versions of ext4, f2fs, and ubifs encryption, and it was potentially reachable in any kernel configured with encryption support (CONFIG_EXT4_ENCRYPTION=y, CONFIG_EXT4_FS_ENCRYPTION=y, CONFIG_F2FS_FS_ENCRYPTION=y, or CONFIG_UBIFS_FS_ENCRYPTION=y). Note that older kernels did not use the shared fs/crypto/ code, but due to the potential security implications of this bug, it may still be worthwhile to backport this fix to them. Fixes: b7236e21d55f ("ext4 crypto: reorganize how we store keys in the inode") Signed-off-by: Eric Biggers Signed-off-by: Theodore Ts'o Acked-by: Michael Halcrow Signed-off-by: Greg Kroah-Hartman

metag/ptrace: Reject partial NT_METAG_RPIPE writes

2017-03-31T08:31:46Z

commit 7195ee3120d878259e8d94a5d9f808116f34d5ea upstream. It's not clear what behaviour is sensible when doing partial write of NT_METAG_RPIPE, so just don't bother. This patch assumes that userspace will never rely on a partial SETREGSET in this case, since it's not clear what should happen anyway. Signed-off-by: Dave Martin Acked-by: James Hogan Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

metag/ptrace: Provide default TXSTATUS for short NT_PRSTATUS

2017-03-31T08:31:46Z

commit 5fe81fe98123ce41265c65e95d34418d30d005d1 upstream. Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET to fill TXSTATUS, a well-defined default value is used, based on the task's current value. Suggested-by: James Hogan Signed-off-by: Dave Martin Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

metag/ptrace: Preserve previous registers for short regset write

2017-03-31T08:31:46Z

commit a78ce80d2c9178351b34d78fec805140c29c193e upstream. Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET to fill all the registers, the thread's old registers are preserved. Signed-off-by: Dave Martin Acked-by: James Hogan Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

sparc/ptrace: Preserve previous registers for short regset write

2017-03-31T08:31:46Z

commit d3805c546b275c8cc7d40f759d029ae92c7175f2 upstream. Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET to fill all the registers, the thread's old registers are preserved. Signed-off-by: Dave Martin Acked-by: David S. Miller Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

mips/ptrace: Preserve previous registers for short regset write

2017-03-31T08:31:46Z

commit d614fd58a2834cfe4efa472c33c8f3ce2338b09b upstream. Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET to fill all the registers, the thread's old registers are preserved. Signed-off-by: Dave Martin Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

h8300/ptrace: Fix incorrect register transfer count

2017-03-31T08:31:46Z

commit 502585c7555083d4a949c08350306b9ec196779e upstream. regs_set() and regs_get() are vulnerable to an off-by-1 buffer overrun if CONFIG_CPU_H8S is set, since this adds an extra entry to register_offset[] but not to user_regs_struct. So, iterate over user_regs_struct based on its actual size, not based on the length of register_offset[]. Signed-off-by: Dave Martin Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman