From 5591bf07225523600450edd9e6ad258bb877b779 Mon Sep 17 00:00:00 2001 From: Dan Rosenberg Date: Tue, 28 Sep 2010 14:18:20 -0400 Subject: ALSA: prevent heap corruption in snd_ctl_new() The snd_ctl_new() function in sound/core/control.c allocates space for a snd_kcontrol struct by performing arithmetic operations on a user-provided size without checking for integer overflow. If a user provides a large enough size, an overflow will occur, the allocated chunk will be too small, and a second user-influenced value will be written repeatedly past the bounds of this chunk. This code is reachable by unprivileged users who have permission to open a /dev/snd/controlC* device (on many distros, this is group "audio") via the SNDRV_CTL_IOCTL_ELEM_ADD and SNDRV_CTL_IOCTL_ELEM_REPLACE ioctls. Signed-off-by: Dan Rosenberg Cc: Signed-off-by: Takashi Iwai --- sound/core/control.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'sound') diff --git a/sound/core/control.c b/sound/core/control.c index 070aab49019..45a818002d9 100644 --- a/sound/core/control.c +++ b/sound/core/control.c @@ -31,6 +31,7 @@ /* max number of user-defined controls */ #define MAX_USER_CONTROLS 32 +#define MAX_CONTROL_COUNT 1028 struct snd_kctl_ioctl { struct list_head list; /* list of all ioctls */ @@ -195,6 +196,10 @@ static struct snd_kcontrol *snd_ctl_new(struct snd_kcontrol *control, if (snd_BUG_ON(!control || !control->count)) return NULL; + + if (control->count > MAX_CONTROL_COUNT) + return NULL; + kctl = kzalloc(sizeof(*kctl) + sizeof(struct snd_kcontrol_volatile) * control->count, GFP_KERNEL); if (kctl == NULL) { snd_printk(KERN_ERR "Cannot allocate control instance\n"); -- cgit v1.2.3-70-g09d2 From e913b146493993c8ac33561655c590e58b500c6f Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Thu, 30 Sep 2010 22:59:12 +0200 Subject: ALSA: i2c/other/ak4xx-adda: Fix a compile warning with CONFIG_PROCFS=n Signed-off-by: Takashi Iwai --- sound/i2c/other/ak4xxx-adda.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'sound') diff --git a/sound/i2c/other/ak4xxx-adda.c b/sound/i2c/other/ak4xxx-adda.c index 1adb8a3c2b6..42d7844ecd0 100644 --- a/sound/i2c/other/ak4xxx-adda.c +++ b/sound/i2c/other/ak4xxx-adda.c @@ -900,7 +900,7 @@ static int proc_init(struct snd_akm4xxx *ak) return 0; } #else /* !CONFIG_PROC_FS */ -static int proc_init(struct snd_akm4xxx *ak) {} +static int proc_init(struct snd_akm4xxx *ak) { return 0; } #endif int snd_akm4xxx_build_controls(struct snd_akm4xxx *ak) -- cgit v1.2.3-70-g09d2