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| author | Peilin Ye <yepeilin.cs@gmail.com> | 2020-07-27 11:00:02 +0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab+huawei@kernel.org> | 2020-08-26 17:29:36 +0300 |
| commit | 4ffb879ea648c2b42da4ca992ed3db87e564af69 (patch) | |
| tree | 3a7d497d8c8215edcbe5b466a71f759190689030 /drivers | |
| parent | bec2ddfd39f07ac2c1dec9fd5299424ad75c0a9d (diff) | |
| download | linux-4ffb879ea648c2b42da4ca992ed3db87e564af69.tar.xz | |
media: media/v4l2-core: Fix kernel-infoleak in video_put_user()
video_put_user() is copying uninitialized stack memory to userspace due
to the compiler not initializing holes in the structures declared on the
stack. Fix it by initializing `ev32` and `vb32` using memset().
Reported-and-tested-by: syzbot+79d751604cb6f29fbf59@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?extid=79d751604cb6f29fbf59
Cc: stable@vger.kernel.org
Fixes: 1a6c0b36dd19 ("media: v4l2-core: fix VIDIOC_DQEVENT for time64 ABI")
Fixes: 577c89b0ce72 ("media: v4l2-core: fix v4l2_buffer handling for time64 ABI")
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/media/v4l2-core/v4l2-ioctl.c | 50 |
1 files changed, 27 insertions, 23 deletions
diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c index a556880f225a..e3a25ea913ac 100644 --- a/drivers/media/v4l2-core/v4l2-ioctl.c +++ b/drivers/media/v4l2-core/v4l2-ioctl.c @@ -3189,14 +3189,16 @@ static int video_put_user(void __user *arg, void *parg, unsigned int cmd) #ifdef CONFIG_COMPAT_32BIT_TIME case VIDIOC_DQEVENT_TIME32: { struct v4l2_event *ev = parg; - struct v4l2_event_time32 ev32 = { - .type = ev->type, - .pending = ev->pending, - .sequence = ev->sequence, - .timestamp.tv_sec = ev->timestamp.tv_sec, - .timestamp.tv_nsec = ev->timestamp.tv_nsec, - .id = ev->id, - }; + struct v4l2_event_time32 ev32; + + memset(&ev32, 0, sizeof(ev32)); + + ev32.type = ev->type; + ev32.pending = ev->pending; + ev32.sequence = ev->sequence; + ev32.timestamp.tv_sec = ev->timestamp.tv_sec; + ev32.timestamp.tv_nsec = ev->timestamp.tv_nsec; + ev32.id = ev->id; memcpy(&ev32.u, &ev->u, sizeof(ev->u)); memcpy(&ev32.reserved, &ev->reserved, sizeof(ev->reserved)); @@ -3210,21 +3212,23 @@ static int video_put_user(void __user *arg, void *parg, unsigned int cmd) case VIDIOC_DQBUF_TIME32: case VIDIOC_PREPARE_BUF_TIME32: { struct v4l2_buffer *vb = parg; - struct v4l2_buffer_time32 vb32 = { - .index = vb->index, - .type = vb->type, - .bytesused = vb->bytesused, - .flags = vb->flags, - .field = vb->field, - .timestamp.tv_sec = vb->timestamp.tv_sec, - .timestamp.tv_usec = vb->timestamp.tv_usec, - .timecode = vb->timecode, - .sequence = vb->sequence, - .memory = vb->memory, - .m.userptr = vb->m.userptr, - .length = vb->length, - .request_fd = vb->request_fd, - }; + struct v4l2_buffer_time32 vb32; + + memset(&vb32, 0, sizeof(vb32)); + + vb32.index = vb->index; + vb32.type = vb->type; + vb32.bytesused = vb->bytesused; + vb32.flags = vb->flags; + vb32.field = vb->field; + vb32.timestamp.tv_sec = vb->timestamp.tv_sec; + vb32.timestamp.tv_usec = vb->timestamp.tv_usec; + vb32.timecode = vb->timecode; + vb32.sequence = vb->sequence; + vb32.memory = vb->memory; + vb32.m.userptr = vb->m.userptr; + vb32.length = vb->length; + vb32.request_fd = vb->request_fd; if (copy_to_user(arg, &vb32, sizeof(vb32))) return -EFAULT; |