From: Xiaomeng Tong <xiam0nd.tong@xxxxxxxxx> 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@xxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx Fixes: ad85094b293e4 ("Revert "media: staging: atomisp: Remove driver"") Signed-off-by: Xiaomeng Tong <xiam0nd.tong@xxxxxxxxx> Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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 @@ -899,9 +899,9 @@ 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; @@ -940,60 +940,75 @@ 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: