[PATCH] paride/pcd: return earlier when an error happens in pcd_atapi()

[Tom Rix]

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@xxxxxxxxxx>
---
 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;
 
-			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