[PATCH 5.17 0310/1126] media: meson: vdec: potential dereference of null pointer

From: Greg Kroah-Hartman
Date: Tue Apr 05 2022 - 04:51:16 EST


From: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>

[ Upstream commit c8c80c996182239ff9b05eda4db50184cf3b2e99 ]

As the possible failure of the kzalloc(), the 'new_ts' could be NULL
pointer.
Therefore, it should be better to check it in order to avoid the
dereference of the NULL pointer.
Also, the caller esparser_queue() needs to deal with the return value of
the amvdec_add_ts().

Fixes: 876f123b8956 ("media: meson: vdec: bring up to compliance")
Signed-off-by: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>
Suggested-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
Reviewed-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/staging/media/meson/vdec/esparser.c | 7 ++++++-
drivers/staging/media/meson/vdec/vdec_helpers.c | 8 ++++++--
drivers/staging/media/meson/vdec/vdec_helpers.h | 4 ++--
3 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/staging/media/meson/vdec/esparser.c b/drivers/staging/media/meson/vdec/esparser.c
index db7022707ff8..86ccc8937afc 100644
--- a/drivers/staging/media/meson/vdec/esparser.c
+++ b/drivers/staging/media/meson/vdec/esparser.c
@@ -328,7 +328,12 @@ esparser_queue(struct amvdec_session *sess, struct vb2_v4l2_buffer *vbuf)

offset = esparser_get_offset(sess);

- amvdec_add_ts(sess, vb->timestamp, vbuf->timecode, offset, vbuf->flags);
+ ret = amvdec_add_ts(sess, vb->timestamp, vbuf->timecode, offset, vbuf->flags);
+ if (ret) {
+ v4l2_m2m_buf_done(vbuf, VB2_BUF_STATE_ERROR);
+ return ret;
+ }
+
dev_dbg(core->dev, "esparser: ts = %llu pld_size = %u offset = %08X flags = %08X\n",
vb->timestamp, payload_size, offset, vbuf->flags);

diff --git a/drivers/staging/media/meson/vdec/vdec_helpers.c b/drivers/staging/media/meson/vdec/vdec_helpers.c
index 203d7afa085d..7d2a75653250 100644
--- a/drivers/staging/media/meson/vdec/vdec_helpers.c
+++ b/drivers/staging/media/meson/vdec/vdec_helpers.c
@@ -227,13 +227,16 @@ int amvdec_set_canvases(struct amvdec_session *sess,
}
EXPORT_SYMBOL_GPL(amvdec_set_canvases);

-void amvdec_add_ts(struct amvdec_session *sess, u64 ts,
- struct v4l2_timecode tc, u32 offset, u32 vbuf_flags)
+int amvdec_add_ts(struct amvdec_session *sess, u64 ts,
+ struct v4l2_timecode tc, u32 offset, u32 vbuf_flags)
{
struct amvdec_timestamp *new_ts;
unsigned long flags;

new_ts = kzalloc(sizeof(*new_ts), GFP_KERNEL);
+ if (!new_ts)
+ return -ENOMEM;
+
new_ts->ts = ts;
new_ts->tc = tc;
new_ts->offset = offset;
@@ -242,6 +245,7 @@ void amvdec_add_ts(struct amvdec_session *sess, u64 ts,
spin_lock_irqsave(&sess->ts_spinlock, flags);
list_add_tail(&new_ts->list, &sess->timestamps);
spin_unlock_irqrestore(&sess->ts_spinlock, flags);
+ return 0;
}
EXPORT_SYMBOL_GPL(amvdec_add_ts);

diff --git a/drivers/staging/media/meson/vdec/vdec_helpers.h b/drivers/staging/media/meson/vdec/vdec_helpers.h
index 88137d15aa3a..4bf3e61d081b 100644
--- a/drivers/staging/media/meson/vdec/vdec_helpers.h
+++ b/drivers/staging/media/meson/vdec/vdec_helpers.h
@@ -56,8 +56,8 @@ void amvdec_dst_buf_done_offset(struct amvdec_session *sess,
* @offset: offset in the VIFIFO where the associated packet was written
* @flags: the vb2_v4l2_buffer flags
*/
-void amvdec_add_ts(struct amvdec_session *sess, u64 ts,
- struct v4l2_timecode tc, u32 offset, u32 flags);
+int amvdec_add_ts(struct amvdec_session *sess, u64 ts,
+ struct v4l2_timecode tc, u32 offset, u32 flags);
void amvdec_remove_ts(struct amvdec_session *sess, u64 ts);

/**
--
2.34.1