linux-kernel - [PATCH 5.10 115/167] ALSA: pcm: Fix mmap capability check

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 26 Jul 2021 17:39:08 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Takashi Iwai <tiwai@...e.de>
Subject: [PATCH 5.10 115/167] ALSA: pcm: Fix mmap capability check

From: Takashi Iwai <tiwai@...e.de>

commit c4824ae7db418aee6f50f308a20b832e58e997fd upstream.

The hw_support_mmap() doesn't cover all memory allocation types and
might use a wrong device pointer for checking the capability.
Check the all memory allocation types more completely.

Cc: <stable@...r.kernel.org>
Link: https://lore.kernel.org/r/20210720092640.12338-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@...e.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 sound/core/pcm_native.c |   14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -246,12 +246,18 @@ static bool hw_support_mmap(struct snd_p
 	if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_MMAP))
 		return false;
 
-	if (substream->ops->mmap ||
-	    (substream->dma_buffer.dev.type != SNDRV_DMA_TYPE_DEV &&
-	     substream->dma_buffer.dev.type != SNDRV_DMA_TYPE_DEV_UC))
+	if (substream->ops->mmap)
 		return true;
 
-	return dma_can_mmap(substream->dma_buffer.dev.dev);
+	switch (substream->dma_buffer.dev.type) {
+	case SNDRV_DMA_TYPE_UNKNOWN:
+		return false;
+	case SNDRV_DMA_TYPE_CONTINUOUS:
+	case SNDRV_DMA_TYPE_VMALLOC:
+		return true;
+	default:
+		return dma_can_mmap(substream->dma_buffer.dev.dev);
+	}
 }
 
 static int constrain_mask_params(struct snd_pcm_substream *substream,