Since commit 9ba9d11544f9 ("media: ivtv: Access v4l2_fh from file") all ioctl handlers have been ported to operate on the file * first function argument.
The ivtv DVB layer calls ivtv_init_on_first_open() when the driver needs to start streaming. This function calls the s_input() and s_frequency() ioctl handlers directly, but being called from the driver context, it doesn't have a valid file * to pass them. This causes the ioctl handlers to deference an invalid pointer.
Fix this by wrapping the ioctl handlers implementation in helper functions which accepts a ivtv_open_id pointer as first argument and make the ivtv_init_on_first_open() function call the helpers without going through the ioctl handlers.
The bug has been reported by Smatch.
Reported-by: Dan Carpenter dan.carpenter@linaro.org Closes: https://lore.kernel.org/all/aKL4OMWsESUdX8KQ@stanley.mountain/ Fixes: 9ba9d11544f9 ("media: ivtv: Access v4l2_fh from file") Signed-off-by: Jacopo Mondi jacopo.mondi@ideasonboard.com --- drivers/media/pci/ivtv/ivtv-driver.c | 4 ++-- drivers/media/pci/ivtv/ivtv-ioctl.c | 22 +++++++++++++++++----- drivers/media/pci/ivtv/ivtv-ioctl.h | 6 ++++-- 3 files changed, 23 insertions(+), 9 deletions(-)
diff --git a/drivers/media/pci/ivtv/ivtv-driver.c b/drivers/media/pci/ivtv/ivtv-driver.c index ecc20cd89926fe2ce4e472526a6b5fc0857615dd..bcbb03271047df9b127039759dbfefbaae67f9c3 100644 --- a/drivers/media/pci/ivtv/ivtv-driver.c +++ b/drivers/media/pci/ivtv/ivtv-driver.c @@ -1310,13 +1310,13 @@ int ivtv_init_on_first_open(struct ivtv *itv)
video_input = itv->active_input; itv->active_input++; /* Force update of input */ - ivtv_s_input(NULL, &fh, video_input); + ivtv_do_s_input(&fh, video_input);
/* Let the VIDIOC_S_STD ioctl do all the work, keeps the code in one place. */ itv->std++; /* Force full standard initialization */ itv->std_out = itv->std; - ivtv_s_frequency(NULL, &fh, &vf); + ivtv_do_s_frequency(&fh, &vf);
if (itv->card->v4l2_capabilities & V4L2_CAP_VIDEO_OUTPUT) { /* Turn on the TV-out: ivtv_init_mpeg_decoder() initializes diff --git a/drivers/media/pci/ivtv/ivtv-ioctl.c b/drivers/media/pci/ivtv/ivtv-ioctl.c index 8077a71d4850ec773caa20c3fca08f92f3117d69..ba1fce42a8d6d7d9a3779bfc9dfd310060e61103 100644 --- a/drivers/media/pci/ivtv/ivtv-ioctl.c +++ b/drivers/media/pci/ivtv/ivtv-ioctl.c @@ -974,9 +974,9 @@ static int ivtv_g_input(struct file *file, void *fh, unsigned int *i) return 0; }
-int ivtv_s_input(struct file *file, void *fh, unsigned int inp) +int ivtv_do_s_input(struct ivtv_open_id *id, unsigned int inp) { - struct ivtv *itv = file2id(file)->itv; + struct ivtv *itv = id->itv; v4l2_std_id std; int i;
@@ -1017,6 +1017,11 @@ int ivtv_s_input(struct file *file, void *fh, unsigned int inp) return 0; }
+static int ivtv_s_input(struct file *file, void *fh, unsigned int inp) +{ + return ivtv_do_s_input(file2id(file), inp); +} + static int ivtv_g_output(struct file *file, void *fh, unsigned int *i) { struct ivtv *itv = file2id(file)->itv; @@ -1065,10 +1070,11 @@ static int ivtv_g_frequency(struct file *file, void *fh, struct v4l2_frequency * return 0; }
-int ivtv_s_frequency(struct file *file, void *fh, const struct v4l2_frequency *vf) +int ivtv_do_s_frequency(struct ivtv_open_id *id, + const struct v4l2_frequency *vf) { - struct ivtv *itv = file2id(file)->itv; - struct ivtv_stream *s = &itv->streams[file2id(file)->type]; + struct ivtv *itv = id->itv; + struct ivtv_stream *s = &itv->streams[id->type];
if (s->vdev.vfl_dir) return -ENOTTY; @@ -1082,6 +1088,12 @@ int ivtv_s_frequency(struct file *file, void *fh, const struct v4l2_frequency *v return 0; }
+static int ivtv_s_frequency(struct file *file, void *fh, + const struct v4l2_frequency *vf) +{ + return ivtv_do_s_frequency(file2id(file), vf); +} + static int ivtv_g_std(struct file *file, void *fh, v4l2_std_id *std) { struct ivtv *itv = file2id(file)->itv; diff --git a/drivers/media/pci/ivtv/ivtv-ioctl.h b/drivers/media/pci/ivtv/ivtv-ioctl.h index 42c2516379fcbbd0640820ab0e3abe9bf00b57ea..7c91b8963b420761c2afcab1dece4d19a4ec0322 100644 --- a/drivers/media/pci/ivtv/ivtv-ioctl.h +++ b/drivers/media/pci/ivtv/ivtv-ioctl.h @@ -17,7 +17,9 @@ int ivtv_set_speed(struct ivtv *itv, int speed); void ivtv_set_funcs(struct video_device *vdev); void ivtv_s_std_enc(struct ivtv *itv, v4l2_std_id std); void ivtv_s_std_dec(struct ivtv *itv, v4l2_std_id std); -int ivtv_s_frequency(struct file *file, void *fh, const struct v4l2_frequency *vf); -int ivtv_s_input(struct file *file, void *fh, unsigned int inp); + +struct ivtv_open_id; +int ivtv_do_s_frequency(struct ivtv_open_id *id, const struct v4l2_frequency *vf); +int ivtv_do_s_input(struct ivtv_open_id *id, unsigned int inp);
#endif