user/sven/linux.git/drivers/base/component.c, branch v4.19.107

component: do not dereference opaque pointer in debugfs

2020-02-01T09:37:03Z

commit ef9ffc1e5f1ac73ecd2fb3b70db2a3b2472ff2f7 upstream. The match data does not have to be a struct device pointer, and indeed very often is not. Attempt to treat it as such easily results in a crash. For the components that are not registered, we don't know which device is missing. Once it it is there, we can use the struct component to get the device and whether it's bound or not. Fixes: 59e73854b5fd ('component: add debugfs support') Signed-off-by: Lubomir Rintel Cc: stable Cc: Arnaud Pouliquen Link: https://lore.kernel.org/r/20191118115431.63626-1-lkundrak@v3.sk Signed-off-by: Greg Kroah-Hartman

component: fix loop condition to call unbind() if bind() fails

2019-11-20T17:46:47Z

[ Upstream commit bdae566d5d9733b6e32b378668b84eadf28a94d4 ] During component_bind_all(), if bind() fails for any particular component associated with a master, unbind() should be called for all previous components in that master's match array, whose bind() might have completed successfully. As per the current logic, if bind() fails for the component at position 'n' in the master's match array, it would start calling unbind() from component in 'n'th position itself and work backwards, and will always skip calling unbind() for component in 0th position in the master's match array. Fix this by updating the loop condition, and the logic to refer to the components in master's match array, so that unbind() is called for all components starting from 'n-1'st position in the array, until (and including) component in 0th position. Signed-off-by: Banajit Goswami Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

component: add debugfs support

2017-12-18T15:51:11Z

Currently there is no information in any vfs about which devices a master component consists of, what makes debugging hard if one of the component devices fails to register. Add 'device_component' directory to debugfs. Create a new file for each component master, when it has been added. Remove it on a master deletion. Show a list of devices required by the given master and their status (registered or not). This provides an easy way to check, which device has failed to register if the given master device is not available in the system. Signed-off-by: Maciej Purski Signed-off-by: Greg Kroah-Hartman

driver core: Remove redundant license text

2017-12-07T17:36:44Z

Now that the SPDX tag is in all driver core files, that identifies the license in a specific and legally-defined manner. So the extra GPL text wording can be removed as it is no longer needed at all. This is done on a quest to remove the 700+ different ways that files in the kernel describe the GPL license text. And there's unneeded stuff like the address (sometimes incorrect) for the FSF which is never needed. No copyright headers or other non-license-description text was removed. Cc: Johannes Berg Cc: "Luis R. Rodriguez" Signed-off-by: Greg Kroah-Hartman

driver core: add SPDX identifiers to all driver core files

2017-12-07T17:36:43Z

It's good to have SPDX identifiers in all files to make it easier to audit the kernel tree for correct licenses. Update the driver core files files with the correct SPDX license identifier based on the license text in the file itself. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This work is based on a script and data from Thomas Gleixner, Philippe Ombredanne, and Kate Stewart. Cc: Johannes Berg Cc: "Luis R. Rodriguez" Cc: William Breathitt Gray Cc: Thomas Gleixner Cc: Kate Stewart Cc: Philippe Ombredanne Signed-off-by: Greg Kroah-Hartman

Merge 4.5-rc4 into driver-core-next

2016-02-14T22:29:55Z

We want the fixes in here as well. Signed-off-by: Greg Kroah-Hartman

component: remove device from master match list on failed add

2016-02-11T09:42:09Z

Calling component_add() may result in the completion of a set of devices, which will try to bring up a master. In bringing the master up, we populate its match array with the current set of children. If binding any of the devices fails, component_add() itself will fail, free the struct component entry, and return to the caller. The now-freed entry is never removed from the master's match array, and will later be used in a futile attempt to bind to freed memory. Bring component_add's behaviour on failure to bring up a master into line with component_del by removing the (to-be-freed) component from the master's match array. The specific case which broke was: - rockchip_drm_drv adds a component master - dwhdmi_rockchip adds a child component in probe (master incomplete) - rockchip_drm_vop adds two children in probe, which completes the set - inside component_add, we try to bring up the master, having populated the master's match array, and fail with EPROBE_DEFER from dwhdmi_rockchip; we delete the putative component - rockchip_drm_vop's probe fails and returns EPROBE_DEFER - we later re-probe rockchip_drm_vop and add the component; the master is complete, so we attempt to bring it up again - walking the match array, we find the previous child, whose master pointer doesn't match (as it has been freed in the meantime) - rockchip_drm_vop probe fails, and will never be attempted again Fixes: ffc30b74fd6d01588bd3fdebc3b1acc0857e6fc8 Signed-off-by: Daniel Stone Cc: Russell King Cc: Thierry Reding Cc: Laurent Pinchart Signed-off-by: Russell King

component: remove impossible condition

2016-02-10T01:39:33Z

We will be evaluating this condition only if match->num == match->alloc and that means we have already dereferenced match which implies match can not be NULL at this point. Moreover we have done a NULL check on match just before this. Signed-off-by: Sudip Mukherjee Signed-off-by: Greg Kroah-Hartman

component: Detach components when deleting master struct

2016-01-27T19:07:51Z

component_master_add_with_match calls find_components which, if any components already exist, it attaches to the master struct. However, if we later encounter an error the master struct is deleted, leaving components with a dangling pointer to it. If the error was a temporary one, e.g. for probe deferral, then when the master device is re-probed, it will fail to find the required components as they appear to already be attached to a master. Fix this by nulling components pointers to the master struct when it is deleted. This code is factored out into a separate function so it can be shared with component_master_del. Signed-off-by: Jon Medhurst Signed-off-by: Russell King

component: fix crash on x86_64 with hda audio drivers

2016-01-26T18:13:33Z

Maarten reports that the addition of releasing match data to the component helper results in a general protection fault on x86_64. This is caused by the devm resources being freed in reverse order to their allocation, which caused a use-after-free of the match array. Switch the match array to be a more conventional kmalloc/kfree() affair, explicitly freeing it along with the parent match data structure. Reported-by: Maarten Lankhorst Fixes: ce657b1cddf1 ("component: add support for releasing match data") Signed-off-by: Russell King