diff mbox series

[10/14] ALSA: emu10k1: validate min/max values of translated controls

Message ID 20230510173917.3073107-11-oswald.buddenhagen@gmx.de
State Accepted
Commit 1a38ae579606dae836dced573d5ffa78cce6fc48
Headers show
Series ALSA: emu10k1: various improvements to the DSP-based mixer code | expand

Commit Message

Oswald Buddenhagen May 10, 2023, 5:39 p.m. UTC 
User space could pass arbitrary ranges, which were uncritically
accepted. This could lead to table lookups out of range.

I don't think that this is a security issue, as it only allowed someone
with CAP_SYS_ADMIN to crash the kernel, but still.

Setting an invalid translation mode will also be rejected now. That did
no harm, but it's still better to detect errors.

Signed-off-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
---
 sound/pci/emu10k1/emufx.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)
diff mbox series

Patch

diff --git a/sound/pci/emu10k1/emufx.c b/sound/pci/emu10k1/emufx.c
index 53b32f005cf7..01d69e496696 100644
--- a/sound/pci/emu10k1/emufx.c
+++ b/sound/pci/emu10k1/emufx.c
@@ -769,6 +769,32 @@  static int snd_emu10k1_verify_controls(struct snd_emu10k1 *emu,
 			err = -EINVAL;
 			goto __error;
 		}
+		switch (gctl->translation) {
+		case EMU10K1_GPR_TRANSLATION_NONE:
+			break;
+		case EMU10K1_GPR_TRANSLATION_TABLE100:
+			if (gctl->min != 0 || gctl->max != 100) {
+				err = -EINVAL;
+				goto __error;
+			}
+			break;
+		case EMU10K1_GPR_TRANSLATION_BASS:
+		case EMU10K1_GPR_TRANSLATION_TREBLE:
+			if (gctl->min != 0 || gctl->max != 40) {
+				err = -EINVAL;
+				goto __error;
+			}
+			break;
+		case EMU10K1_GPR_TRANSLATION_ONOFF:
+			if (gctl->min != 0 || gctl->max != 1) {
+				err = -EINVAL;
+				goto __error;
+			}
+			break;
+		default:
+			err = -EINVAL;
+			goto __error;
+		}
 	}
 	for (i = 0; i < icode->gpr_list_control_count; i++) {
 	     	/* FIXME: we need to check the WRITE access */