linux

[media] media: Media device node support The media_devnode structure provides support for registering and unregistering character devices using a dynamic major number. Reference counting is handled internally, making device drivers easier to write without having to solve the open/disconnect race condition issue over and over again. The code is based on video/v4l2-dev.c. [mchehab@redhat.com: Remove linux/smp_lock.h include to not break compilation on bisect] Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2009-12-09 08:39:56 -03:00

[media] media-device: dynamically allocate struct media_devnode struct media_devnode is currently embedded at struct media_device. While this works fine during normal usage, it leads to a race condition during devnode unregister. the problem is that drivers assume that, after calling media_device_unregister(), the struct that contains media_device can be freed. This is not true, as it can't be freed until userspace closes all opened /dev/media devnodes. In other words, if the media devnode is still open, and media_device gets freed, any call to an ioctl will make the core to try to access struct media_device, with will cause an use-after-free and even GPF. Fix this by dynamically allocating the struct media_devnode and only freeing it when it is safe. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-04-27 19:28:26 -03:00

[media] media: Media device node support The media_devnode structure provides support for registering and unregistering character devices using a dynamic major number. Reference counting is handled internally, making device drivers easier to write without having to solve the open/disconnect race condition issue over and over again. The code is based on video/v4l2-dev.c. [mchehab@redhat.com: Remove linux/smp_lock.h include to not break compilation on bisect] Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2009-12-09 08:39:56 -03:00

[media] media-devnode.h: document the remaining struct/functions There is one struct and two functions that were not documented. Add the corresponding kernel-doc documentation for them. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

2015-12-13 09:00:00 -02:00

[media] media: Media device node support The media_devnode structure provides support for registering and unregistering character devices using a dynamic major number. Reference counting is handled internally, making device drivers easier to write without having to solve the open/disconnect race condition issue over and over again. The code is based on video/v4l2-dev.c. [mchehab@redhat.com: Remove linux/smp_lock.h include to not break compilation on bisect] Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2009-12-09 08:39:56 -03:00

->poll() methods should return __poll_t The most common place to find POLL... bitmaps: return values of ->poll() and its subsystem counterparts. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2017-07-02 22:22:01 -04:00

[media] media: Media device node support The media_devnode structure provides support for registering and unregistering character devices using a dynamic major number. Reference counting is handled internally, making device drivers easier to write without having to solve the open/disconnect race condition issue over and over again. The code is based on video/v4l2-dev.c. [mchehab@redhat.com: Remove linux/smp_lock.h include to not break compilation on bisect] Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2009-12-09 08:39:56 -03:00

[media] media: Add 64--32 bit compat ioctl handler Provide an ioctl handler for 32-bit binaries on 64-bit systems. Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2013-01-22 12:27:55 -03:00

[media] media: Media device node support The media_devnode structure provides support for registering and unregistering character devices using a dynamic major number. Reference counting is handled internally, making device drivers easier to write without having to solve the open/disconnect race condition issue over and over again. The code is based on video/v4l2-dev.c. [mchehab@redhat.com: Remove linux/smp_lock.h include to not break compilation on bisect] Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2009-12-09 08:39:56 -03:00

[media] media-devnode.h: Fix documentation Two parameters were documented with a wrong name, and a struct device pointer description was missing. That caused the following warnings, when building documentation: include/media/media-devnode.h:102: warning: No description found for parameter 'media_dev' include/media/media-devnode.h:126: warning: No description found for parameter 'mdev' include/media/media-devnode.h:126: warning: Excess function parameter 'media_dev' description in 'media_devnode_register' Rename the description, to match the function parameter and fix Documentation. No funcional changes. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-06-16 08:04:40 -03:00

[media] media-devnode.h: document the remaining struct/functions There is one struct and two functions that were not documented. Add the corresponding kernel-doc documentation for them. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

2015-12-13 09:00:00 -02:00

[media] media-devnode.h: Fix documentation Two parameters were documented with a wrong name, and a struct device pointer description was missing. That caused the following warnings, when building documentation: include/media/media-devnode.h:102: warning: No description found for parameter 'media_dev' include/media/media-devnode.h:126: warning: No description found for parameter 'mdev' include/media/media-devnode.h:126: warning: Excess function parameter 'media_dev' description in 'media_devnode_register' Rename the description, to match the function parameter and fix Documentation. No funcional changes. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-06-16 08:04:40 -03:00

[media] Docbook: Fix description of struct media_devnode Warning(.//include/media/media-devnode.h:80): No description found for parameter 'fops' Warning(.//include/media/media-devnode.h:80): No description found for parameter 'dev' Warning(.//include/media/media-devnode.h:80): No description found for parameter 'cdev' Warning(.//include/media/media-devnode.h:80): No description found for parameter 'release' Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Acked-by: Jonathan Corbet <corbet@lwn.net>

2015-08-22 04:45:03 -03:00

[media] media: Media device node support The media_devnode structure provides support for registering and unregistering character devices using a dynamic major number. Reference counting is handled internally, making device drivers easier to write without having to solve the open/disconnect race condition issue over and over again. The code is based on video/v4l2-dev.c. [mchehab@redhat.com: Remove linux/smp_lock.h include to not break compilation on bisect] Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2009-12-09 08:39:56 -03:00

[media] docs-rst: improve the kAPI documentation for the mediactl There are several issues on the documentation: - the media.h header were not properly referenced; - verbatim expressions were not properly marked as such; - struct member references were wrong; - some notes were not using the right markup; - a comment that were moved to the kernel-doc markup were duplicated as a comment inside the struct media_entity; - some args were not pointing to the struct they're using; - macros weren't documented. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-08-29 16:09:11 -03:00

[media] mc-core.rst: fix a warning about an internal routine Fix this warning: Documentation/media/kapi/mc-core.rst:97: WARNING: c:func reference target not found: media_devnode_release The media_device_release() is a function internal to media-devnode.c, and not exported elsewhere. So, we can't cross-reference it here. Make it explicit at the documentation. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-09-08 09:57:24 -03:00

[media] media: Media device node support The media_devnode structure provides support for registering and unregistering character devices using a dynamic major number. Reference counting is handled internally, making device drivers easier to write without having to solve the open/disconnect race condition issue over and over again. The code is based on video/v4l2-dev.c. [mchehab@redhat.com: Remove linux/smp_lock.h include to not break compilation on bisect] Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2009-12-09 08:39:56 -03:00

[media] media-device: dynamically allocate struct media_devnode struct media_devnode is currently embedded at struct media_device. While this works fine during normal usage, it leads to a race condition during devnode unregister. the problem is that drivers assume that, after calling media_device_unregister(), the struct that contains media_device can be freed. This is not true, as it can't be freed until userspace closes all opened /dev/media devnodes. In other words, if the media devnode is still open, and media_device gets freed, any call to an ioctl will make the core to try to access struct media_device, with will cause an use-after-free and even GPF. Fix this by dynamically allocating the struct media_devnode and only freeing it when it is safe. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-04-27 19:28:26 -03:00

[media] media: Media device node support The media_devnode structure provides support for registering and unregistering character devices using a dynamic major number. Reference counting is handled internally, making device drivers easier to write without having to solve the open/disconnect race condition issue over and over again. The code is based on video/v4l2-dev.c. [mchehab@redhat.com: Remove linux/smp_lock.h include to not break compilation on bisect] Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2009-12-09 08:39:56 -03:00

[media] media-devnode: fix namespace mess Along all media controller code, "mdev" is used to represent a pointer to struct media_device, and "devnode" for a pointer to struct media_devnode. However, inside media-devnode.[ch], "mdev" is used to represent a pointer to struct media_devnode. This is very confusing and may lead to development errors. So, let's change all occurrences at media-devnode.[ch] to also use "devnode" for such pointers. This patch doesn't make any functional changes. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-03-23 11:22:57 -03:00

[media] media: Media device node support The media_devnode structure provides support for registering and unregistering character devices using a dynamic major number. Reference counting is handled internally, making device drivers easier to write without having to solve the open/disconnect race condition issue over and over again. The code is based on video/v4l2-dev.c. [mchehab@redhat.com: Remove linux/smp_lock.h include to not break compilation on bisect] Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2009-12-09 08:39:56 -03:00

[media] media-devnode: move kernel-doc documentation to the header As we're using the headers file only for documentation, move the two kernel-doc macros to the header, and fix it to avoid warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

2015-12-13 08:40:45 -02:00

[media] media-devnode.h: Fix documentation Two parameters were documented with a wrong name, and a struct device pointer description was missing. That caused the following warnings, when building documentation: include/media/media-devnode.h:102: warning: No description found for parameter 'media_dev' include/media/media-devnode.h:126: warning: No description found for parameter 'mdev' include/media/media-devnode.h:126: warning: Excess function parameter 'media_dev' description in 'media_devnode_register' Rename the description, to match the function parameter and fix Documentation. No funcional changes. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-06-16 08:04:40 -03:00

[media] media-devnode: fix namespace mess Along all media controller code, "mdev" is used to represent a pointer to struct media_device, and "devnode" for a pointer to struct media_devnode. However, inside media-devnode.[ch], "mdev" is used to represent a pointer to struct media_devnode. This is very confusing and may lead to development errors. So, let's change all occurrences at media-devnode.[ch] to also use "devnode" for such pointers. This patch doesn't make any functional changes. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-03-23 11:22:57 -03:00

[media] media-devnode: move kernel-doc documentation to the header As we're using the headers file only for documentation, move the two kernel-doc macros to the header, and fix it to avoid warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

2015-12-13 08:40:45 -02:00

[media] media-device: dynamically allocate struct media_devnode struct media_devnode is currently embedded at struct media_device. While this works fine during normal usage, it leads to a race condition during devnode unregister. the problem is that drivers assume that, after calling media_device_unregister(), the struct that contains media_device can be freed. This is not true, as it can't be freed until userspace closes all opened /dev/media devnodes. In other words, if the media devnode is still open, and media_device gets freed, any call to an ioctl will make the core to try to access struct media_device, with will cause an use-after-free and even GPF. Fix this by dynamically allocating the struct media_devnode and only freeing it when it is safe. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-04-27 19:28:26 -03:00

[media] media: Use a better owner for the media device mdev->fops->owner is actually the owner of the very same module which implements media_device_register(), so it can't be unloaded anyway. Instead, use THIS_MODULE through a macro as does video_register_device(). Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

2013-12-12 12:38:17 -03:00

[media] media-devnode: move kernel-doc documentation to the header As we're using the headers file only for documentation, move the two kernel-doc macros to the header, and fix it to avoid warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

2015-12-13 08:40:45 -02:00

[media] media: fix media devnode ioctl/syscall and unregister race Media devnode open/ioctl could be in progress when media device unregister is initiated. System calls and ioctls check media device registered status at the beginning, however, there is a window where unregister could be in progress without changing the media devnode status to unregistered. process 1 process 2 fd = open(/dev/media0) media_devnode_is_registered() (returns true here) media_device_unregister() (unregister is in progress and devnode isn't unregistered yet) ... ioctl(fd, ...) __media_ioctl() media_devnode_is_registered() (returns true here) ... media_devnode_unregister() ... (driver releases the media device memory) media_device_ioctl() (By this point devnode->media_dev does not point to allocated memory. use-after free in in mutex_lock_nested) BUG: KASAN: use-after-free in mutex_lock_nested+0x79c/0x800 at addr ffff8801ebe914f0 Fix it by clearing register bit when unregister starts to avoid the race. process 1 process 2 fd = open(/dev/media0) media_devnode_is_registered() (could return true here) media_device_unregister() (clear the register bit, then start unregister.) ... ioctl(fd, ...) __media_ioctl() media_devnode_is_registered() (return false here, ioctl returns I/O error, and will not access media device memory) ... media_devnode_unregister() ... (driver releases the media device memory) Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com> Suggested-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reported-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Tested-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-06-10 14:37:23 -03:00

[media] media-devnode: move kernel-doc documentation to the header As we're using the headers file only for documentation, move the two kernel-doc macros to the header, and fix it to avoid warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

2015-12-13 08:40:45 -02:00

[media] media-devnode: fix namespace mess Along all media controller code, "mdev" is used to represent a pointer to struct media_device, and "devnode" for a pointer to struct media_devnode. However, inside media-devnode.[ch], "mdev" is used to represent a pointer to struct media_devnode. This is very confusing and may lead to development errors. So, let's change all occurrences at media-devnode.[ch] to also use "devnode" for such pointers. This patch doesn't make any functional changes. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-03-23 11:22:57 -03:00

[media] media-devnode: move kernel-doc documentation to the header As we're using the headers file only for documentation, move the two kernel-doc macros to the header, and fix it to avoid warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

2015-12-13 08:40:45 -02:00

[media] media: fix media devnode ioctl/syscall and unregister race Media devnode open/ioctl could be in progress when media device unregister is initiated. System calls and ioctls check media device registered status at the beginning, however, there is a window where unregister could be in progress without changing the media devnode status to unregistered. process 1 process 2 fd = open(/dev/media0) media_devnode_is_registered() (returns true here) media_device_unregister() (unregister is in progress and devnode isn't unregistered yet) ... ioctl(fd, ...) __media_ioctl() media_devnode_is_registered() (returns true here) ... media_devnode_unregister() ... (driver releases the media device memory) media_device_ioctl() (By this point devnode->media_dev does not point to allocated memory. use-after free in in mutex_lock_nested) BUG: KASAN: use-after-free in mutex_lock_nested+0x79c/0x800 at addr ffff8801ebe914f0 Fix it by clearing register bit when unregister starts to avoid the race. process 1 process 2 fd = open(/dev/media0) media_devnode_is_registered() (could return true here) media_device_unregister() (clear the register bit, then start unregister.) ... ioctl(fd, ...) __media_ioctl() media_devnode_is_registered() (return false here, ioctl returns I/O error, and will not access media device memory) ... media_devnode_unregister() ... (driver releases the media device memory) Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com> Suggested-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reported-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Tested-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-06-10 14:37:23 -03:00

[media] media-devnode: move kernel-doc documentation to the header As we're using the headers file only for documentation, move the two kernel-doc macros to the header, and fix it to avoid warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

2015-12-13 08:40:45 -02:00

[media] media-devnode: fix namespace mess Along all media controller code, "mdev" is used to represent a pointer to struct media_device, and "devnode" for a pointer to struct media_devnode. However, inside media-devnode.[ch], "mdev" is used to represent a pointer to struct media_devnode. This is very confusing and may lead to development errors. So, let's change all occurrences at media-devnode.[ch] to also use "devnode" for such pointers. This patch doesn't make any functional changes. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-03-23 11:22:57 -03:00

[media] media: Media device node support The media_devnode structure provides support for registering and unregistering character devices using a dynamic major number. Reference counting is handled internally, making device drivers easier to write without having to solve the open/disconnect race condition issue over and over again. The code is based on video/v4l2-dev.c. [mchehab@redhat.com: Remove linux/smp_lock.h include to not break compilation on bisect] Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2009-12-09 08:39:56 -03:00

[media] media-devnode.h: document the remaining struct/functions There is one struct and two functions that were not documented. Add the corresponding kernel-doc documentation for them. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

2015-12-13 09:00:00 -02:00

[media] media: Media device node support The media_devnode structure provides support for registering and unregistering character devices using a dynamic major number. Reference counting is handled internally, making device drivers easier to write without having to solve the open/disconnect race condition issue over and over again. The code is based on video/v4l2-dev.c. [mchehab@redhat.com: Remove linux/smp_lock.h include to not break compilation on bisect] Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2009-12-09 08:39:56 -03:00

[media] media-devnode.h: document the remaining struct/functions There is one struct and two functions that were not documented. Add the corresponding kernel-doc documentation for them. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

2015-12-13 09:00:00 -02:00

[media] media-devnode: fix namespace mess Along all media controller code, "mdev" is used to represent a pointer to struct media_device, and "devnode" for a pointer to struct media_devnode. However, inside media-devnode.[ch], "mdev" is used to represent a pointer to struct media_devnode. This is very confusing and may lead to development errors. So, let's change all occurrences at media-devnode.[ch] to also use "devnode" for such pointers. This patch doesn't make any functional changes. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-03-23 11:22:57 -03:00

[media] media-device: dynamically allocate struct media_devnode struct media_devnode is currently embedded at struct media_device. While this works fine during normal usage, it leads to a race condition during devnode unregister. the problem is that drivers assume that, after calling media_device_unregister(), the struct that contains media_device can be freed. This is not true, as it can't be freed until userspace closes all opened /dev/media devnodes. In other words, if the media devnode is still open, and media_device gets freed, any call to an ioctl will make the core to try to access struct media_device, with will cause an use-after-free and even GPF. Fix this by dynamically allocating the struct media_devnode and only freeing it when it is safe. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-04-27 19:28:26 -03:00

[media] media-devnode.h: document the remaining struct/functions There is one struct and two functions that were not documented. Add the corresponding kernel-doc documentation for them. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

2015-12-13 09:00:00 -02:00

[media] media-devnode: fix namespace mess Along all media controller code, "mdev" is used to represent a pointer to struct media_device, and "devnode" for a pointer to struct media_devnode. However, inside media-devnode.[ch], "mdev" is used to represent a pointer to struct media_devnode. This is very confusing and may lead to development errors. So, let's change all occurrences at media-devnode.[ch] to also use "devnode" for such pointers. This patch doesn't make any functional changes. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-03-23 11:22:57 -03:00

[media] media: Media device node support The media_devnode structure provides support for registering and unregistering character devices using a dynamic major number. Reference counting is handled internally, making device drivers easier to write without having to solve the open/disconnect race condition issue over and over again. The code is based on video/v4l2-dev.c. [mchehab@redhat.com: Remove linux/smp_lock.h include to not break compilation on bisect] Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2009-12-09 08:39:56 -03:00

[media] media-device: dynamically allocate struct media_devnode struct media_devnode is currently embedded at struct media_device. While this works fine during normal usage, it leads to a race condition during devnode unregister. the problem is that drivers assume that, after calling media_device_unregister(), the struct that contains media_device can be freed. This is not true, as it can't be freed until userspace closes all opened /dev/media devnodes. In other words, if the media devnode is still open, and media_device gets freed, any call to an ioctl will make the core to try to access struct media_device, with will cause an use-after-free and even GPF. Fix this by dynamically allocating the struct media_devnode and only freeing it when it is safe. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-04-27 19:28:26 -03:00

[media] media-devnode: fix namespace mess Along all media controller code, "mdev" is used to represent a pointer to struct media_device, and "devnode" for a pointer to struct media_devnode. However, inside media-devnode.[ch], "mdev" is used to represent a pointer to struct media_devnode. This is very confusing and may lead to development errors. So, let's change all occurrences at media-devnode.[ch] to also use "devnode" for such pointers. This patch doesn't make any functional changes. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

2016-03-23 11:22:57 -03:00

[media] media: Media device node support The media_devnode structure provides support for registering and unregistering character devices using a dynamic major number. Reference counting is handled internally, making device drivers easier to write without having to solve the open/disconnect race condition issue over and over again. The code is based on video/v4l2-dev.c. [mchehab@redhat.com: Remove linux/smp_lock.h include to not break compilation on bisect] Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2009-12-09 08:39:56 -03:00

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176 lines

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