user/sven/linux.git, branch v4.1.50

Linux 4.1.50

2018-03-05T21:35:54Z

Signed-off-by: Sasha Levin

media: v4l2-compat-ioctl32.c: refactor compat ioctl32 logic

2018-03-04T15:28:48Z

commit a1dfb4c48cc1e64eeb7800a27c66a6f7e88d075a upstream. The 32-bit compat v4l2 ioctl handling is implemented based on its 64-bit equivalent. It converts 32-bit data structures into its 64-bit equivalents and needs to provide the data to the 64-bit ioctl in user space memory which is commonly allocated using compat_alloc_user_space(). However, due to how that function is implemented, it can only be called a single time for every syscall invocation. Supposedly to avoid this limitation, the existing code uses a mix of memory from the kernel stack and memory allocated through compat_alloc_user_space(). Under normal circumstances, this would not work, because the 64-bit ioctl expects all pointers to point to user space memory. As a workaround, set_fs(KERNEL_DS) is called to temporarily disable this extra safety check and allow kernel pointers. However, this might introduce a security vulnerability: The result of the 32-bit to 64-bit conversion is writeable by user space because the output buffer has been allocated via compat_alloc_user_space(). A malicious user space process could then manipulate pointers inside this output buffer, and due to the previous set_fs(KERNEL_DS) call, functions like get_user() or put_user() no longer prevent kernel memory access. The new approach is to pre-calculate the total amount of user space memory that is needed, allocate it using compat_alloc_user_space() and then divide up the allocated memory to accommodate all data structures that need to be converted. An alternative approach would have been to retain the union type karg that they allocated on the kernel stack in do_video_ioctl(), copy all data from user space into karg and then back to user space. However, we decided against this approach because it does not align with other compat syscall implementations. Instead, we tried to replicate the get_user/put_user pairs as found in other places in the kernel: if (get_user(clipcount, &up->clipcount) || put_user(clipcount, &kp->clipcount)) return -EFAULT; Notes from hans.verkuil@cisco.com: This patch was taken from: https://github.com/LineageOS/android_kernel_samsung_apq8084/commit/97b733953c06e4f0398ade18850f0817778255f7 Clearly nobody could be bothered to upstream this patch or at minimum tell us :-( We only heard about this a week ago. This patch was rebased and cleaned up. Compared to the original I also swapped the order of the convert_in_user arguments so that they matched copy_in_user. It was hard to review otherwise. I also replaced the ALLOC_USER_SPACE/ALLOC_AND_GET by a normal function. Fixes: 6b5a9492ca ("v4l: introduce string control support.") Signed-off-by: Daniel Mentz Co-developed-by: Hans Verkuil Acked-by: Sakari Ailus Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin

media: v4l2-compat-ioctl32.c: don't copy back the result for certain errors

2018-03-04T15:28:48Z

commit d83a8243aaefe62ace433e4384a4f077bed86acb upstream. Some ioctls need to copy back the result even if the ioctl returned an error. However, don't do this for the error code -ENOTTY. It makes no sense in that cases. Signed-off-by: Hans Verkuil Acked-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin

media: v4l2-compat-ioctl32.c: drop pr_info for unknown buffer type

2018-03-04T15:28:47Z

commit 169f24ca68bf0f247d111aef07af00dd3a02ae88 upstream. There is nothing wrong with using an unknown buffer type. So stop spamming the kernel log whenever this happens. The kernel will just return -EINVAL to signal this. Signed-off-by: Hans Verkuil Acked-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin

media: v4l2-compat-ioctl32.c: copy clip list in put_v4l2_window32

2018-03-04T15:28:47Z

commit a751be5b142ef6bcbbb96d9899516f4d9c8d0ef4 upstream. put_v4l2_window32() didn't copy back the clip list to userspace. Drivers can update the clip rectangles, so this should be done. Signed-off-by: Hans Verkuil Acked-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin

media: v4l2-compat-ioctl32: Copy v4l2_window->global_alpha

2018-03-04T15:28:47Z

commit 025a26fa14f8fd55d50ab284a30c016a5be953d0 upstream. Commit b2787845fb91 ("V4L/DVB (5289): Add support for video output overlays.") added the field global_alpha to struct v4l2_window but did not update the compat layer accordingly. This change adds global_alpha to struct v4l2_window32 and copies the value for global_alpha back and forth. Signed-off-by: Daniel Mentz Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin

media: v4l2-compat-ioctl32.c: make ctrl_is_pointer work for subdevs

2018-03-04T15:28:47Z

commit 273caa260035c03d89ad63d72d8cd3d9e5c5e3f1 upstream. If the device is of type VFL_TYPE_SUBDEV then vdev->ioctl_ops is NULL so the 'if (!ops->vidioc_query_ext_ctrl)' check would crash. Add a test for !ops to the condition. All sub-devices that have controls will use the control framework, so they do not have an equivalent to ops->vidioc_query_ext_ctrl. Returning false if ops is NULL is the correct thing to do here. Fixes: b8c601e8af ("v4l2-compat-ioctl32.c: fix ctrl_is_pointer") Signed-off-by: Hans Verkuil Acked-by: Sakari Ailus Reported-by: Laurent Pinchart Reviewed-by: Laurent Pinchart Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin

media: v4l2-compat-ioctl32.c: fix ctrl_is_pointer

2018-03-04T15:28:47Z

commit b8c601e8af2d08f733d74defa8465303391bb930 upstream. ctrl_is_pointer just hardcoded two known string controls, but that caused problems when using e.g. custom controls that use a pointer for the payload. Reimplement this function: it now finds the v4l2_ctrl (if the driver uses the control framework) or it calls vidioc_query_ext_ctrl (if the driver implements that directly). In both cases it can now check if the control is a pointer control or not. Signed-off-by: Hans Verkuil Acked-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin

media: v4l2-compat-ioctl32.c: copy m.userptr in put_v4l2_plane32

2018-03-04T15:28:47Z

commit 8ed5a59dcb47a6f76034ee760b36e089f3e82529 upstream. The struct v4l2_plane32 should set m.userptr as well. The same happens in v4l2_buffer32 and v4l2-compliance tests for this. Signed-off-by: Hans Verkuil Acked-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin

media: v4l2-compat-ioctl32.c: avoid sizeof(type)

2018-03-04T15:28:47Z

commit 333b1e9f96ce05f7498b581509bb30cde03018bf upstream. Instead of doing sizeof(struct foo) use sizeof(*up). There even were cases where 4 * sizeof(__u32) was used instead of sizeof(kp->reserved), which is very dangerous when the size of the reserved array changes. Signed-off-by: Hans Verkuil Acked-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin