In the Linux kernel, the following vulnerability has been resolved:
media: vimc: skip .s_stream() for stopped entities
Syzbot reported [1] a warning prompted by a check in callsstream() that checks whether .s_stream() operation is warranted for unstarted or stopped subdevs.
Add a simple fix in vimcstreamerpipelineterminate() ensuring that entities skip a call to .sstream() unless they have been previously properly started.
[1] Syzbot report: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 5933 at drivers/media/v4l2-core/v4l2-subdev.c:460 callsstream+0x2df/0x350 drivers/media/v4l2-core/v4l2-subdev.c:460 Modules linked in: CPU: 0 UID: 0 PID: 5933 Comm: syz-executor330 Not tainted 6.13.0-rc2-syzkaller-00362-g2d8308bf5b67 #0 ... Call Trace: <TASK> vimcstreamerpipelineterminate+0x218/0x320 drivers/media/test-drivers/vimc/vimc-streamer.c:62 vimcstreamerpipelineinit drivers/media/test-drivers/vimc/vimc-streamer.c:101 [inline] vimcstreamersstream+0x650/0x9a0 drivers/media/test-drivers/vimc/vimc-streamer.c:203 vimccapturestartstreaming+0xa1/0x130 drivers/media/test-drivers/vimc/vimc-capture.c:256 vb2startstreaming+0x15f/0x5a0 drivers/media/common/videobuf2/videobuf2-core.c:1789 vb2corestreamon+0x2a7/0x450 drivers/media/common/videobuf2/videobuf2-core.c:2348 vb2streamon drivers/media/common/videobuf2/videobuf2-v4l2.c:875 [inline] vb2ioctlstreamon+0xf4/0x170 drivers/media/common/videobuf2/videobuf2-v4l2.c:1118 _videodoioctl+0xaf0/0xf00 drivers/media/v4l2-core/v4l2-ioctl.c:3122 videousercopy+0x4d2/0x1620 drivers/media/v4l2-core/v4l2-ioctl.c:3463 v4l2ioctl+0x1ba/0x250 drivers/media/v4l2-core/v4l2-dev.c:366 vfsioctl fs/ioctl.c:51 [inline] _dosysioctl fs/ioctl.c:906 [inline] _sesysioctl fs/ioctl.c:892 [inline] _x64sysioctl+0x190/0x200 fs/ioctl.c:892 dosyscallx64 arch/x86/entry/common.c:52 [inline] dosyscall64+0xcd/0x250 arch/x86/entry/common.c:83 entrySYSCALL64afterhwframe+0x77/0x7f RIP: 0033:0x7f2b85c01b19 ...