kernel/linux.git/drivers/base, branch v4.19.77

base: soc: Export soc_device_register/unregister APIs

2019-10-05T11:09:37+00:00

[ Upstream commit f7ccc7a397cf2ef64aebb2f726970b93203858d2 ] Qcom Socinfo driver can be built as a module, so export these two APIs. Tested-by: Vinod Koul Signed-off-by: Vinod Koul Signed-off-by: Vaishali Thakkar Reviewed-by: Greg Kroah-Hartman Reviewed-by: Stephen Boyd Reviewed-by: Bjorn Andersson Signed-off-by: Bjorn Andersson Signed-off-by: Sasha Levin

driver core: Fix use-after-free and double free on glue directory

2019-09-19T07:09:37+00:00

commit ac43432cb1f5c2950408534987e57c2071e24d8f upstream. There is a race condition between removing glue directory and adding a new device under the glue dir. It can be reproduced in following test: CPU1: CPU2: device_add() get_device_parent() class_dir_create_and_add() kobject_add_internal() create_dir() // create glue_dir device_add() get_device_parent() kobject_get() // get glue_dir device_del() cleanup_glue_dir() kobject_del(glue_dir) kobject_add() kobject_add_internal() create_dir() // in glue_dir sysfs_create_dir_ns() kernfs_create_dir_ns(sd) sysfs_remove_dir() // glue_dir->sd=NULL sysfs_put() // free glue_dir->sd // sd is freed kernfs_new_node(sd) kernfs_get(glue_dir) kernfs_add_one() kernfs_put() Before CPU1 remove last child device under glue dir, if CPU2 add a new device under glue dir, the glue_dir kobject reference count will be increase to 2 via kobject_get() in get_device_parent(). And CPU2 has been called kernfs_create_dir_ns(), but not call kernfs_new_node(). Meanwhile, CPU1 call sysfs_remove_dir() and sysfs_put(). This result in glue_dir->sd is freed and it's reference count will be 0. Then CPU2 call kernfs_get(glue_dir) will trigger a warning in kernfs_get() and increase it's reference count to 1. Because glue_dir->sd is freed by CPU1, the next call kernfs_add_one() by CPU2 will fail(This is also use-after-free) and call kernfs_put() to decrease reference count. Because the reference count is decremented to 0, it will also call kmem_cache_free() to free the glue_dir->sd again. This will result in double free. In order to avoid this happening, we also should make sure that kernfs_node for glue_dir is released in CPU1 only when refcount for glue_dir kobj is 1 to fix this race. The following calltrace is captured in kernel 4.14 with the following patch applied: commit 726e41097920 ("drivers: core: Remove glue dirs from sysfs earlier") -------------------------------------------------------------------------- [ 3.633703] WARNING: CPU: 4 PID: 513 at .../fs/kernfs/dir.c:494 Here is WARN_ON(!atomic_read(&kn->count) in kernfs_get(). .... [ 3.633986] Call trace: [ 3.633991] kernfs_create_dir_ns+0xa8/0xb0 [ 3.633994] sysfs_create_dir_ns+0x54/0xe8 [ 3.634001] kobject_add_internal+0x22c/0x3f0 [ 3.634005] kobject_add+0xe4/0x118 [ 3.634011] device_add+0x200/0x870 [ 3.634017] _request_firmware+0x958/0xc38 [ 3.634020] request_firmware_into_buf+0x4c/0x70 .... [ 3.634064] kernel BUG at .../mm/slub.c:294! Here is BUG_ON(object == fp) in set_freepointer(). .... [ 3.634346] Call trace: [ 3.634351] kmem_cache_free+0x504/0x6b8 [ 3.634355] kernfs_put+0x14c/0x1d8 [ 3.634359] kernfs_create_dir_ns+0x88/0xb0 [ 3.634362] sysfs_create_dir_ns+0x54/0xe8 [ 3.634366] kobject_add_internal+0x22c/0x3f0 [ 3.634370] kobject_add+0xe4/0x118 [ 3.634374] device_add+0x200/0x870 [ 3.634378] _request_firmware+0x958/0xc38 [ 3.634381] request_firmware_into_buf+0x4c/0x70 -------------------------------------------------------------------------- Fixes: 726e41097920 ("drivers: core: Remove glue dirs from sysfs earlier") Signed-off-by: Muchun Song Reviewed-by: Mukesh Ojha Signed-off-by: Prateek Sood Link: https://lore.kernel.org/r/20190727032122.24639-1-smuchun@gmail.com Signed-off-by: Greg Kroah-Hartman

drivers/base: Introduce kill_device()

2019-08-09T15:52:28+00:00

commit 00289cd87676e14913d2d8492d1ce05c4baafdae upstream. The libnvdimm subsystem arranges for devices to be destroyed as a result of a sysfs operation. Since device_unregister() cannot be called from an actively running sysfs attribute of the same device libnvdimm arranges for device_unregister() to be performed in an out-of-line async context. The driver core maintains a 'dead' state for coordinating its own racing async registration / de-registration requests. Rather than add local 'dead' state tracking infrastructure to libnvdimm device objects, export the existing state tracking via a new kill_device() helper. The kill_device() helper simply marks the device as dead, i.e. that it is on its way to device_del(), or returns that the device was already dead. This can be used in advance of calling device_unregister() for subsystems like libnvdimm that might need to handle multiple user threads racing to delete a device. This refactoring does not change any behavior, but it is a pre-requisite for follow-on fixes and therefore marked for -stable. Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Fixes: 4d88a97aa9e8 ("libnvdimm, nvdimm: dimm driver and base libnvdimm device-driver...") Cc: Tested-by: Jane Chu Reviewed-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/156341207332.292348.14959761496009347574.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams Signed-off-by: Sasha Levin

driver core: Establish order of operations for device_add and device_del via bitflag

2019-08-09T15:52:28+00:00

commit 3451a495ef244a88ed6317a035299d835554d579 upstream. Add an additional bit flag to the device_private struct named "dead". This additional flag provides a guarantee that when a device_del is executed on a given interface an async worker will not attempt to attach the driver following the earlier device_del call. Previously this guarantee was not present and could result in the device_del call attempting to remove a driver from an interface only to have the async worker attempt to probe the driver later when it finally completes the asynchronous probe call. One additional change added was that I pulled the check for dev->driver out of the __device_attach_driver call and instead placed it in the __device_attach_async_helper call. This was motivated by the fact that the only other caller of this, __device_attach, had already taken the device_lock() and checked for dev->driver. Instead of testing for this twice in this path it makes more sense to just consolidate the dev->dead and dev->driver checks together into one set of checks. Reviewed-by: Dan Williams Reviewed-by: Rafael J. Wysocki Signed-off-by: Alexander Duyck Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

regmap: fix bulk writes on paged registers

2019-07-26T07:14:06+00:00

[ Upstream commit db057679de3e9e6a03c1bcd5aee09b0d25fd9f5b ] On buses like SlimBus and SoundWire which does not support gather_writes yet in regmap, A bulk write on paged register would be silently ignored after programming page. This is because local variable 'ret' value in regmap_raw_write_impl() gets reset to 0 once page register is written successfully and the code below checks for 'ret' value to be -ENOTSUPP before linearising the write buffer to send to bus->write(). Fix this by resetting the 'ret' value to -ENOTSUPP in cases where gather_writes() is not supported or single register write is not possible. Signed-off-by: Srinivas Kandagatla Signed-off-by: Mark Brown Signed-off-by: Sasha Levin

regmap: debugfs: Fix memory leak in regmap_debugfs_init

2019-07-26T07:13:58+00:00

[ Upstream commit 2899872b627e99b7586fe3b6c9f861da1b4d5072 ] As detected by kmemleak running on i.MX6ULL board: nreferenced object 0xd8366600 (size 64): comm "swapper/0", pid 1, jiffies 4294937370 (age 933.220s) hex dump (first 32 bytes): 64 75 6d 6d 79 2d 69 6f 6d 75 78 63 2d 67 70 72 dummy-iomuxc-gpr 40 32 30 65 34 30 30 30 00 e3 f3 ab fe d1 1b dd @20e4000........ backtrace: [] kasprintf+0x2c/0x54 [] regmap_debugfs_init+0x7c/0x31c [<9c8d91fa>] __regmap_init+0xb5c/0xcf4 [<5b1c3d2a>] of_syscon_register+0x164/0x2c4 [<596a5d80>] syscon_node_to_regmap+0x64/0x90 [<49bd597b>] imx6ul_init_machine+0x34/0xa0 [<250a4dac>] customize_machine+0x1c/0x30 [<2d19fdaf>] do_one_initcall+0x7c/0x398 [] kernel_init_freeable+0x328/0x448 [<168c9101>] kernel_init+0x8/0x114 [<913268aa>] ret_from_fork+0x14/0x20 [] 0x0 Root cause is that map->debugfs_name is allocated using kasprintf and then the pointer is lost by assigning it other memory address. Reported-by: Stefan Wahren Signed-off-by: Daniel Baluta Signed-off-by: Mark Brown Signed-off-by: Sasha Levin

regmap-irq: do not write mask register if mask_base is zero

2019-07-21T07:03:16+00:00

commit 7151449fe7fa5962c6153355f9779d6be99e8e97 upstream. If client have not provided the mask base register then do not write into the mask register. Signed-off-by: Laxman Dewangan Signed-off-by: Jinyoung Park Signed-off-by: Venkat Reddy Talla Signed-off-by: Mark Zhang Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman

firmware: improve LSM/IMA security behaviour

2019-07-21T07:03:03+00:00

commit 2472d64af2d3561954e2f05365a67692bb852f2a upstream. The firmware loader queries if LSM/IMA permits it to load firmware via the sysfs fallback. Unfortunately, the code does the opposite: it expressly permits sysfs fw loading if security_kernel_load_data( LOADING_FIRMWARE) returns -EACCES. This happens because a zero-on-success return value is cast to a bool that's true on success. Fix the return value handling so we get the correct behaviour. Fixes: 6e852651f28e ("firmware: add call to LSM hook before firmware sysfs fallback") Cc: Stable Cc: Mimi Zohar Cc: Kees Cook To: Luis Chamberlain Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Cc: linux-kernel@vger.kernel.org Signed-off-by: Sven Van Asbroeck Reviewed-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT

2019-07-21T07:03:03+00:00

commit 83b44fe343b5abfcb1b2261289bd0cfcfcfd60a8 upstream. The cacheinfo structures are alloced/freed by cpu online/offline callbacks. Originally these were only used by sysfs to expose the cache topology to user space. Without any in-kernel dependencies CPUHP_AP_ONLINE_DYN was an appropriate choice. resctrl has started using these structures to identify CPUs that share a cache. It updates its 'domain' structures from cpu online/offline callbacks. These depend on the cacheinfo structures (resctrl_online_cpu()->domain_add_cpu()->get_cache_id()-> get_cpu_cacheinfo()). These also run as CPUHP_AP_ONLINE_DYN. Now that there is an in-kernel dependency, move the cacheinfo work earlier so we know its done before resctrl's CPUHP_AP_ONLINE_DYN work runs. Fixes: 2264d9c74dda1 ("x86/intel_rdt: Build structures for each resource based on cache topology") Cc: Cc: Fenghua Yu Cc: Reinette Chatre Signed-off-by: James Morse Link: https://lore.kernel.org/r/20190624173656.202407-1-james.morse@arm.com Signed-off-by: Greg Kroah-Hartman

PM / core: Propagate dev->power.wakeup_path when no callbacks

2019-05-31T13:46:23+00:00

[ Upstream commit dc351d4c5f4fe4d0f274d6d660227be0c3a03317 ] The dev->power.direct_complete flag may become set in device_prepare() in case the device don't have any PM callbacks (dev->power.no_pm_callbacks is set). This leads to a broken behaviour, when there is child having wakeup enabled and relies on its parent to be used in the wakeup path. More precisely, when the direct complete path becomes selected for the child in __device_suspend(), the propagation of the dev->power.wakeup_path becomes skipped as well. Let's address this problem, by checking if the device is a part the wakeup path or has wakeup enabled, then prevent the direct complete path from being used. Reported-by: Loic Pallardy Signed-off-by: Ulf Hansson [ rjw: Comment cleanup ] Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin