paride/pcd: return earlier when an error happens in pcd_atapi()
Commit Message
clang static analysis reports
drivers/block/paride/pcd.c:856:36: warning: The left operand of '&'
is a garbage value [core.UndefinedBinaryOperatorResult]
tocentry->cdte_ctrl = buffer[5] & 0xf;
~~~~~~~~~ ^
When the call to pcd_atapi() fails, buffer[] is in an unknown state,
so return early.
Signed-off-by: Tom Rix <trix@redhat.com>
---
drivers/block/paride/pcd.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
Comments
On Sat, Jan 14, 2023 at 9:01 AM Tom Rix <trix@redhat.com> wrote:
>
> clang static analysis reports
> drivers/block/paride/pcd.c:856:36: warning: The left operand of '&'
> is a garbage value [core.UndefinedBinaryOperatorResult]
> tocentry->cdte_ctrl = buffer[5] & 0xf;
> ~~~~~~~~~ ^
>
> When the call to pcd_atapi() fails, buffer[] is in an unknown state,
> so return early.
>
> Signed-off-by: Tom Rix <trix@redhat.com>
> ---
> drivers/block/paride/pcd.c | 11 ++++++-----
> 1 file changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/block/paride/pcd.c b/drivers/block/paride/pcd.c
> index a5ab40784119..4524d8880463 100644
> --- a/drivers/block/paride/pcd.c
> +++ b/drivers/block/paride/pcd.c
> @@ -827,12 +827,13 @@ static int pcd_audio_ioctl(struct cdrom_device_info *cdi, unsigned int cmd, void
> char buffer[32];
> int r;
Hi Tom, Thanks for the patch!
It looks like `r` is now unused; mind removing that in v2?
Same below.
>
> - r = pcd_atapi(cd, cmd, 12, buffer, "read toc header");
> + if (pcd_atapi(cd, cmd, 12, buffer, "read toc header"))
> + return -EIO;
>
> tochdr->cdth_trk0 = buffer[2];
> tochdr->cdth_trk1 = buffer[3];
>
> - return r ? -EIO : 0;
> + return 0;
> }
>
> case CDROMREADTOCENTRY:
> @@ -845,13 +846,13 @@ static int pcd_audio_ioctl(struct cdrom_device_info *cdi, unsigned int cmd, void
> struct cdrom_tocentry *tocentry =
> (struct cdrom_tocentry *) arg;
> unsigned char buffer[32];
> - int r;
^
>
> cmd[1] =
> (tocentry->cdte_format == CDROM_MSF ? 0x02 : 0);
> cmd[6] = tocentry->cdte_track;
>
> - r = pcd_atapi(cd, cmd, 12, buffer, "read toc entry");
> + if (pcd_atapi(cd, cmd, 12, buffer, "read toc entry"))
> + return -EIO;
>
> tocentry->cdte_ctrl = buffer[5] & 0xf;
> tocentry->cdte_adr = buffer[5] >> 4;
> @@ -866,7 +867,7 @@ static int pcd_audio_ioctl(struct cdrom_device_info *cdi, unsigned int cmd, void
> (((((buffer[8] << 8) + buffer[9]) << 8)
> + buffer[10]) << 8) + buffer[11];
>
> - return r ? -EIO : 0;
> + return 0;
> }
>
> default:
> --
> 2.27.0
>
>
@@ -827,12 +827,13 @@ static int pcd_audio_ioctl(struct cdrom_device_info *cdi, unsigned int cmd, void
char buffer[32];
int r;
- r = pcd_atapi(cd, cmd, 12, buffer, "read toc header");
+ if (pcd_atapi(cd, cmd, 12, buffer, "read toc header"))
+ return -EIO;
tochdr->cdth_trk0 = buffer[2];
tochdr->cdth_trk1 = buffer[3];
- return r ? -EIO : 0;
+ return 0;
}
case CDROMREADTOCENTRY:
@@ -845,13 +846,13 @@ static int pcd_audio_ioctl(struct cdrom_device_info *cdi, unsigned int cmd, void
struct cdrom_tocentry *tocentry =
(struct cdrom_tocentry *) arg;
unsigned char buffer[32];
- int r;
cmd[1] =
(tocentry->cdte_format == CDROM_MSF ? 0x02 : 0);
cmd[6] = tocentry->cdte_track;
- r = pcd_atapi(cd, cmd, 12, buffer, "read toc entry");
+ if (pcd_atapi(cd, cmd, 12, buffer, "read toc entry"))
+ return -EIO;
tocentry->cdte_ctrl = buffer[5] & 0xf;
tocentry->cdte_adr = buffer[5] >> 4;
@@ -866,7 +867,7 @@ static int pcd_audio_ioctl(struct cdrom_device_info *cdi, unsigned int cmd, void
(((((buffer[8] << 8) + buffer[9]) << 8)
+ buffer[10]) << 8) + buffer[11];
- return r ? -EIO : 0;
+ return 0;
}
default: