kernel/linux.git, branch v4.19.172

Linux 4.19.172

2021-01-30T12:32:13+00:00

Tested-by: Pavel Machek (CIP) Link: https://lore.kernel.org/r/20210129105910.685105711@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

fs: fix lazytime expiration handling in __writeback_single_inode()

2021-01-30T12:32:13+00:00

commit 1e249cb5b7fc09ff216aa5a12f6c302e434e88f9 upstream. When lazytime is enabled and an inode is being written due to its in-memory updated timestamps having expired, either due to a sync() or syncfs() system call or due to dirtytime_expire_interval having elapsed, the VFS needs to inform the filesystem so that the filesystem can copy the inode's timestamps out to the on-disk data structures. This is done by __writeback_single_inode() calling mark_inode_dirty_sync(), which then calls ->dirty_inode(I_DIRTY_SYNC). However, this occurs after __writeback_single_inode() has already cleared the dirty flags from ->i_state. This causes two bugs: - mark_inode_dirty_sync() redirties the inode, causing it to remain dirty. This wastefully causes the inode to be written twice. But more importantly, it breaks cases where sync_filesystem() is expected to clean dirty inodes. This includes the FS_IOC_REMOVE_ENCRYPTION_KEY ioctl (as reported at https://lore.kernel.org/r/20200306004555.GB225345@gmail.com), as well as possibly filesystem freezing (freeze_super()). - Since ->i_state doesn't contain I_DIRTY_TIME when ->dirty_inode() is called from __writeback_single_inode() for lazytime expiration, xfs_fs_dirty_inode() ignores the notification. (XFS only cares about lazytime expirations, and it assumes that i_state will contain I_DIRTY_TIME during those.) Therefore, lazy timestamps aren't persisted by sync(), syncfs(), or dirtytime_expire_interval on XFS. Fix this by moving the call to mark_inode_dirty_sync() to earlier in __writeback_single_inode(), before the dirty flags are cleared from i_state. This makes filesystems be properly notified of the timestamp expiration, and it avoids incorrectly redirtying the inode. This fixes xfstest generic/580 (which tests FS_IOC_REMOVE_ENCRYPTION_KEY) when run on ext4 or f2fs with lazytime enabled. It also fixes the new lazytime xfstest I've proposed, which reproduces the above-mentioned XFS bug (https://lore.kernel.org/r/20210105005818.92978-1-ebiggers@kernel.org). Alternatively, we could call ->dirty_inode(I_DIRTY_SYNC) directly. But due to the introduction of I_SYNC_QUEUED, mark_inode_dirty_sync() is the right thing to do because mark_inode_dirty_sync() now knows not to move the inode to a writeback list if it is currently queued for sync. Fixes: 0ae45f63d4ef ("vfs: add support for a lazytime mount option") Cc: stable@vger.kernel.org Depends-on: 5afced3bf281 ("writeback: Avoid skipping inode writeback") Link: https://lore.kernel.org/r/20210112190253.64307-2-ebiggers@kernel.org Suggested-by: Jan Kara Reviewed-by: Christoph Hellwig Reviewed-by: Jan Kara Signed-off-by: Eric Biggers Signed-off-by: Jan Kara Signed-off-by: Greg Kroah-Hartman

writeback: Drop I_DIRTY_TIME_EXPIRE

2021-01-30T12:32:13+00:00

commit 5fcd57505c002efc5823a7355e21f48dd02d5a51 upstream. The only use of I_DIRTY_TIME_EXPIRE is to detect in __writeback_single_inode() that inode got there because flush worker decided it's time to writeback the dirty inode time stamps (either because we are syncing or because of age). However we can detect this directly in __writeback_single_inode() and there's no need for the strange propagation with I_DIRTY_TIME_EXPIRE flag. Reviewed-by: Christoph Hellwig Signed-off-by: Jan Kara Signed-off-by: Eric Biggers Signed-off-by: Greg Kroah-Hartman

dm integrity: conditionally disable "recalculate" feature

2021-01-30T12:32:13+00:00

commit 5c02406428d5219c367c5f53457698c58bc5f917 upstream. Otherwise a malicious user could (ab)use the "recalculate" feature that makes dm-integrity calculate the checksums in the background while the device is already usable. When the system restarts before all checksums have been calculated, the calculation continues where it was interrupted even if the recalculate feature is not requested the next time the dm device is set up. Disable recalculating if we use internal_hash or journal_hash with a key (e.g. HMAC) and we don't have the "legacy_recalculate" flag. This may break activation of a volume, created by an older kernel, that is not yet fully recalculated -- if this happens, the user should add the "legacy_recalculate" flag to constructor parameters. Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka Reported-by: Daniel Glockner Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

tools: Factor HOSTCC, HOSTLD, HOSTAR definitions

2021-01-30T12:32:13+00:00

commit c8a950d0d3b926a02c7b2e713850d38217cec3d1 upstream. Several Makefiles in tools/ need to define the host toolchain variables. Move their definition to tools/scripts/Makefile.include Signed-off-by: Jean-Philippe Brucker Signed-off-by: Andrii Nakryiko Acked-by: Jiri Olsa Acked-by: Rafael J. Wysocki Link: https://lore.kernel.org/bpf/20201110164310.2600671-2-jean-philippe@linaro.org Cc: Alistair Delva Signed-off-by: Greg Kroah-Hartman

tracing: Fix race in trace_open and buffer resize call

2021-01-30T12:32:13+00:00

commit bbeb97464eefc65f506084fd9f18f21653e01137 upstream. Below race can come, if trace_open and resize of cpu buffer is running parallely on different cpus CPUX CPUY ring_buffer_resize atomic_read(&buffer->resize_disabled) tracing_open tracing_reset_online_cpus ring_buffer_reset_cpu rb_reset_cpu rb_update_pages remove/insert pages resetting pointer This race can cause data abort or some times infinte loop in rb_remove_pages and rb_insert_pages while checking pages for sanity. Take buffer lock to fix this. Link: https://lkml.kernel.org/r/1601976833-24377-1-git-send-email-gkohli@codeaurora.org Cc: stable@vger.kernel.org Fixes: 83f40318dab00 ("ring-buffer: Make removal of ring buffer pages atomic") Reported-by: Denis Efremov Signed-off-by: Gaurav Kohli Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman

HID: wacom: Correct NULL dereference on AES pen proximity

2021-01-30T12:32:13+00:00

commit 179e8e47c02a1950f1c556f2b854bdb2259078fb upstream. The recent commit to fix a memory leak introduced an inadvertant NULL pointer dereference. The `wacom_wac->pen_fifo` variable was never intialized, resuling in a crash whenever functions tried to use it. Since the FIFO is only used by AES pens (to buffer events from pen proximity until the hardware reports the pen serial number) this would have been easily overlooked without testing an AES device. This patch converts `wacom_wac->pen_fifo` over to a pointer (since the call to `devres_alloc` allocates memory for us) and ensures that we assign it to point to the allocated and initalized `pen_fifo` before the function returns. Link: https://github.com/linuxwacom/input-wacom/issues/230 Fixes: 37309f47e2f5 ("HID: wacom: Fix memory leakage caused by kfifo_alloc") CC: stable@vger.kernel.org # v4.19+ Signed-off-by: Jason Gerecke Tested-by: Ping Cheng Signed-off-by: Jiri Kosina Signed-off-by: Greg Kroah-Hartman

futex: Handle faults correctly for PI futexes

2021-01-30T12:32:13+00:00

commit 34b1a1ce1458f50ef27c54e28eb9b1947012907a upstream fixup_pi_state_owner() tries to ensure that the state of the rtmutex, pi_state and the user space value related to the PI futex are consistent before returning to user space. In case that the user space value update faults and the fault cannot be resolved by faulting the page in via fault_in_user_writeable() the function returns with -EFAULT and leaves the rtmutex and pi_state owner state inconsistent. A subsequent futex_unlock_pi() operates on the inconsistent pi_state and releases the rtmutex despite not owning it which can corrupt the RB tree of the rtmutex and cause a subsequent kernel stack use after free. It was suggested to loop forever in fixup_pi_state_owner() if the fault cannot be resolved, but that results in runaway tasks which is especially undesired when the problem happens due to a programming error and not due to malice. As the user space value cannot be fixed up, the proper solution is to make the rtmutex and the pi_state consistent so both have the same owner. This leaves the user space value out of sync. Any subsequent operation on the futex will fail because the 10th rule of PI futexes (pi_state owner and user space value are consistent) has been violated. As a consequence this removes the inept attempts of 'fixing' the situation in case that the current task owns the rtmutex when returning with an unresolvable fault by unlocking the rtmutex which left pi_state::owner and rtmutex::owner out of sync in a different and only slightly less dangerous way. Fixes: 1b7558e457ed ("futexes: fix fault handling in futex_lock_pi") Reported-by: gzobqq@gmail.com Signed-off-by: Thomas Gleixner Acked-by: Peter Zijlstra (Intel) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

futex: Simplify fixup_pi_state_owner()

2021-01-30T12:32:12+00:00

commit f2dac39d93987f7de1e20b3988c8685523247ae2 upstream Too many gotos already and an upcoming fix would make it even more unreadable. Signed-off-by: Thomas Gleixner Acked-by: Peter Zijlstra (Intel) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

futex: Use pi_state_update_owner() in put_pi_state()

2021-01-30T12:32:12+00:00

commit 6ccc84f917d33312eb2846bd7b567639f585ad6d upstream No point in open coding it. This way it gains the extra sanity checks. Signed-off-by: Thomas Gleixner Acked-by: Peter Zijlstra (Intel) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman