[PATCH 5.19 0123/1157] media: [PATCH] pci: atomisp_cmd: fix three missing checks on list iterator

Greg Kroah-Hartman
2022-08-15T22:25:02Z

From: Xiaomeng Tong <xiam0nd.tong@gmail.com>

commit 09b204eb9de9fdf07d028c41c4331b5cfeb70dd7 upstream.

The three bugs are here:
__func__, s3a_buf->s3a_data->exp_id);
__func__, md_buf->metadata->exp_id);
__func__, dis_buf->dis_data->exp_id);

The list iterator 's3a_buf/md_buf/dis_buf' will point to a bogus
position containing HEAD if the list is empty or no element is found.
This case must be checked before any use of the iterator, otherwise
it will lead to a invalid memory access.

To fix this bug, add an check. Use a new variable '*_iter' as the
list iterator, while use the old variable '*_buf' as a dedicated
pointer to point to the found element.

Link: https://lore.kernel.org/linux-media/20220414041415.3342-1-xiam0nd.tong@gmail.com
Cc: stable@vger.kernel.org
Fixes: ad85094b293e4 ("Revert "media: staging: atomisp: Remove driver"")
Signed-off-by: Xiaomeng Tong <xiam0nd.tong@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/staging/media/atomisp/pci/atomisp_cmd.c | 57 +++++++++++++++---------
1 file changed, 36 insertions(+), 21 deletions(-)

--- a/drivers/staging/media/atomisp/pci/atomisp_cmd.c
+++ b/drivers/staging/media/atomisp/pci/atomisp_cmd.c
@@ -901,9 +901,9 @@ void atomisp_buf_done(struct atomisp_sub
int err;
unsigned long irqflags;
struct ia_css_frame *frame = NULL;
- struct atomisp_s3a_buf *s3a_buf = NULL, *_s3a_buf_tmp;
- struct atomisp_dis_buf *dis_buf = NULL, *_dis_buf_tmp;
- struct atomisp_metadata_buf *md_buf = NULL, *_md_buf_tmp;
+ struct atomisp_s3a_buf *s3a_buf = NULL, *_s3a_buf_tmp, *s3a_iter;
+ struct atomisp_dis_buf *dis_buf = NULL, *_dis_buf_tmp, *dis_iter;
+ struct atomisp_metadata_buf *md_buf = NULL, *_md_buf_tmp, *md_iter;
enum atomisp_metadata_type md_type;
struct atomisp_device *isp = asd->isp;
struct v4l2_control ctrl;
@@ -942,60 +942,75 @@ void atomisp_buf_done(struct atomisp_sub

switch (buf_type) {
case IA_CSS_BUFFER_TYPE_3A_STATISTICS:
- list_for_each_entry_safe(s3a_buf, _s3a_buf_tmp,
+ list_for_each_entry_safe(s3a_iter, _s3a_buf_tmp,
&asd->s3a_stats_in_css, list) {
- if (s3a_buf->s3a_data ==
+ if (s3a_iter->s3a_data ==
buffer.css_buffer.data.stats_3a) {
- list_del_init(&s3a_buf->list);
- list_add_tail(&s3a_buf->list,
+ list_del_init(&s3a_iter->list);
+ list_add_tail(&s3a_iter->list,
&asd->s3a_stats_ready);
+ s3a_buf = s3a_iter;
break;
}
}

asd->s3a_bufs_in_css[css_pipe_id]--;
atomisp_3a_stats_ready_event(asd, buffer.css_buffer.exp_id);
- dev_dbg(isp->dev, "%s: s3a stat with exp_id %d is ready\n",
- __func__, s3a_buf->s3a_data->exp_id);
+ if (s3a_buf)
+ dev_dbg(isp->dev, "%s: s3a stat with exp_id %d is ready\n",
+ __func__, s3a_buf->s3a_data->exp_id);
+ else
+ dev_dbg(isp->dev, "%s: s3a stat is ready with no exp_id found\n",
+ __func__);
break;
case IA_CSS_BUFFER_TYPE_METADATA:
if (error)
break;

md_type = atomisp_get_metadata_type(asd, css_pipe_id);
- list_for_each_entry_safe(md_buf, _md_buf_tmp,
+ list_for_each_entry_safe(md_iter, _md_buf_tmp,
&asd->metadata_in_css[md_type], list) {
- if (md_buf->metadata ==
+ if (md_iter->metadata ==
buffer.css_buffer.data.metadata) {
- list_del_init(&md_buf->list);
- list_add_tail(&md_buf->list,
+ list_del_init(&md_iter->list);
+ list_add_tail(&md_iter->list,
&asd->metadata_ready[md_type]);
+ md_buf = md_iter;
break;
}
}
asd->metadata_bufs_in_css[stream_id][css_pipe_id]--;
atomisp_metadata_ready_event(asd, md_type);
- dev_dbg(isp->dev, "%s: metadata with exp_id %d is ready\n",
- __func__, md_buf->metadata->exp_id);
+ if (md_buf)
+ dev_dbg(isp->dev, "%s: metadata with exp_id %d is ready\n",
+ __func__, md_buf->metadata->exp_id);
+ else
+ dev_dbg(isp->dev, "%s: metadata is ready with no exp_id found\n",
+ __func__);
break;
case IA_CSS_BUFFER_TYPE_DIS_STATISTICS:
- list_for_each_entry_safe(dis_buf, _dis_buf_tmp,
+ list_for_each_entry_safe(dis_iter, _dis_buf_tmp,
&asd->dis_stats_in_css, list) {
- if (dis_buf->dis_data ==
+ if (dis_iter->dis_data ==
buffer.css_buffer.data.stats_dvs) {
spin_lock_irqsave(&asd->dis_stats_lock,
irqflags);
- list_del_init(&dis_buf->list);
- list_add(&dis_buf->list, &asd->dis_stats);
+ list_del_init(&dis_iter->list);
+ list_add(&dis_iter->list, &asd->dis_stats);
asd->params.dis_proj_data_valid = true;
spin_unlock_irqrestore(&asd->dis_stats_lock,
irqflags);
+ dis_buf = dis_iter;
break;
}
}
asd->dis_bufs_in_css--;
- dev_dbg(isp->dev, "%s: dis stat with exp_id %d is ready\n",
- __func__, dis_buf->dis_data->exp_id);
+ if (dis_buf)
+ dev_dbg(isp->dev, "%s: dis stat with exp_id %d is ready\n",
+ __func__, dis_buf->dis_data->exp_id);
+ else
+ dev_dbg(isp->dev, "%s: dis stat is ready with no exp_id found\n",
+ __func__);
break;
case IA_CSS_BUFFER_TYPE_VF_OUTPUT_FRAME:
case IA_CSS_BUFFER_TYPE_SEC_VF_OUTPUT_FRAME: