[alsa-devel] [PATCH 2/5] ALSA: info - Check file position validity in common layer
Takashi Iwai
tiwai at suse.de
Wed Apr 14 10:18:00 CEST 2010
Check the validity of the file position in the common info layer before
calling read or write callbacks in assumption that entry->size is set up
properly to indicate the max file size.
Removed the redundant checks from the callbacks as well.
Signed-off-by: Takashi Iwai <tiwai at suse.de>
---
sound/core/info.c | 14 +++++++++--
sound/drivers/opl4/opl4_proc.c | 46 ++++++++++++++--------------------------
sound/isa/gus/gus_mem_proc.c | 14 +++--------
sound/pci/cs4281.c | 24 +++++---------------
sound/pci/cs46xx/cs46xx_lib.c | 12 ++-------
sound/pci/emu10k1/emuproc.c | 43 +++++++++++++++++--------------------
sound/pci/mixart/mixart.c | 12 ----------
7 files changed, 60 insertions(+), 105 deletions(-)
diff --git a/sound/core/info.c b/sound/core/info.c
index ff968be..f90a6fd 100644
--- a/sound/core/info.c
+++ b/sound/core/info.c
@@ -232,10 +232,15 @@ static ssize_t snd_info_entry_read(struct file *file, char __user *buffer,
return -EFAULT;
break;
case SNDRV_INFO_CONTENT_DATA:
- if (entry->c.ops->read)
+ if (pos >= entry->size)
+ return 0;
+ if (entry->c.ops->read) {
+ size = entry->size - pos;
+ size = min(count, size);
size = entry->c.ops->read(entry,
data->file_private_data,
- file, buffer, count, pos);
+ file, buffer, size, pos);
+ }
break;
}
if ((ssize_t) size > 0)
@@ -282,10 +287,13 @@ static ssize_t snd_info_entry_write(struct file *file, const char __user *buffer
size = count;
break;
case SNDRV_INFO_CONTENT_DATA:
- if (entry->c.ops->write)
+ if (entry->c.ops->write && count > 0) {
+ size_t maxsize = entry->size - pos;
+ count = min(count, maxsize);
size = entry->c.ops->write(entry,
data->file_private_data,
file, buffer, count, pos);
+ }
break;
}
if ((ssize_t) size > 0)
diff --git a/sound/drivers/opl4/opl4_proc.c b/sound/drivers/opl4/opl4_proc.c
index eb72814..210b89d 100644
--- a/sound/drivers/opl4/opl4_proc.c
+++ b/sound/drivers/opl4/opl4_proc.c
@@ -55,25 +55,18 @@ static ssize_t snd_opl4_mem_proc_read(struct snd_info_entry *entry,
size_t count, loff_t pos)
{
struct snd_opl4 *opl4 = entry->private_data;
- long size;
char* buf;
- size = count;
- if (pos + size > entry->size)
- size = entry->size - pos;
- if (size > 0) {
- buf = vmalloc(size);
- if (!buf)
- return -ENOMEM;
- snd_opl4_read_memory(opl4, buf, pos, size);
- if (copy_to_user(_buf, buf, size)) {
- vfree(buf);
- return -EFAULT;
- }
+ buf = vmalloc(count);
+ if (!buf)
+ return -ENOMEM;
+ snd_opl4_read_memory(opl4, buf, pos, count);
+ if (copy_to_user(_buf, buf, count)) {
vfree(buf);
- return size;
+ return -EFAULT;
}
- return 0;
+ vfree(buf);
+ return count;
}
static ssize_t snd_opl4_mem_proc_write(struct snd_info_entry *entry,
@@ -83,25 +76,18 @@ static ssize_t snd_opl4_mem_proc_write(struct snd_info_entry *entry,
size_t count, size_t pos)
{
struct snd_opl4 *opl4 = entry->private_data;
- long size;
char *buf;
- size = count;
- if (pos + size > entry->size)
- size = entry->size - pos;
- if (size > 0) {
- buf = vmalloc(size);
- if (!buf)
- return -ENOMEM;
- if (copy_from_user(buf, _buf, size)) {
- vfree(buf);
- return -EFAULT;
- }
- snd_opl4_write_memory(opl4, buf, pos, size);
+ buf = vmalloc(count);
+ if (!buf)
+ return -ENOMEM;
+ if (copy_from_user(buf, _buf, count)) {
vfree(buf);
- return size;
+ return -EFAULT;
}
- return 0;
+ snd_opl4_write_memory(opl4, buf, pos, count);
+ vfree(buf);
+ return count;
}
static loff_t snd_opl4_mem_proc_llseek(struct snd_info_entry *entry,
diff --git a/sound/isa/gus/gus_mem_proc.c b/sound/isa/gus/gus_mem_proc.c
index b2d2dba..faa2bec 100644
--- a/sound/isa/gus/gus_mem_proc.c
+++ b/sound/isa/gus/gus_mem_proc.c
@@ -36,20 +36,14 @@ static ssize_t snd_gf1_mem_proc_dump(struct snd_info_entry *entry,
struct file *file, char __user *buf,
size_t count, loff_t pos)
{
- long size;
struct gus_proc_private *priv = entry->private_data;
struct snd_gus_card *gus = priv->gus;
int err;
- size = count;
- if (pos + size > priv->size)
- size = (long)priv->size - pos;
- if (size > 0) {
- if ((err = snd_gus_dram_read(gus, buf, pos, size, priv->rom)) < 0)
- return err;
- return size;
- }
- return 0;
+ err = snd_gus_dram_read(gus, buf, pos, count, priv->rom);
+ if (err < 0)
+ return err;
+ return count;
}
static loff_t snd_gf1_mem_proc_llseek(struct snd_info_entry *entry,
diff --git a/sound/pci/cs4281.c b/sound/pci/cs4281.c
index b0bba2e..6772070 100644
--- a/sound/pci/cs4281.c
+++ b/sound/pci/cs4281.c
@@ -1144,17 +1144,11 @@ static ssize_t snd_cs4281_BA0_read(struct snd_info_entry *entry,
struct file *file, char __user *buf,
size_t count, loff_t pos)
{
- long size;
struct cs4281 *chip = entry->private_data;
- size = count;
- if (pos + size > CS4281_BA0_SIZE)
- size = (long)CS4281_BA0_SIZE - pos;
- if (size > 0) {
- if (copy_to_user_fromio(buf, chip->ba0 + pos, size))
- return -EFAULT;
- }
- return size;
+ if (copy_to_user_fromio(buf, chip->ba0 + pos, count))
+ return -EFAULT;
+ return count;
}
static ssize_t snd_cs4281_BA1_read(struct snd_info_entry *entry,
@@ -1162,17 +1156,11 @@ static ssize_t snd_cs4281_BA1_read(struct snd_info_entry *entry,
struct file *file, char __user *buf,
size_t count, loff_t pos)
{
- long size;
struct cs4281 *chip = entry->private_data;
- size = count;
- if (pos + size > CS4281_BA1_SIZE)
- size = (long)CS4281_BA1_SIZE - pos;
- if (size > 0) {
- if (copy_to_user_fromio(buf, chip->ba1 + pos, size))
- return -EFAULT;
- }
- return size;
+ if (copy_to_user_fromio(buf, chip->ba1 + pos, count))
+ return -EFAULT;
+ return count;
}
static struct snd_info_entry_ops snd_cs4281_proc_ops_BA0 = {
diff --git a/sound/pci/cs46xx/cs46xx_lib.c b/sound/pci/cs46xx/cs46xx_lib.c
index 08117b1..aad3708 100644
--- a/sound/pci/cs46xx/cs46xx_lib.c
+++ b/sound/pci/cs46xx/cs46xx_lib.c
@@ -2662,17 +2662,11 @@ static ssize_t snd_cs46xx_io_read(struct snd_info_entry *entry,
struct file *file, char __user *buf,
size_t count, loff_t pos)
{
- long size;
struct snd_cs46xx_region *region = entry->private_data;
- size = count;
- if (pos + (size_t)size > region->size)
- size = region->size - pos;
- if (size > 0) {
- if (copy_to_user_fromio(buf, region->remap_addr + pos, size))
- return -EFAULT;
- }
- return size;
+ if (copy_to_user_fromio(buf, region->remap_addr + pos, count))
+ return -EFAULT;
+ return count;
}
static struct snd_info_entry_ops snd_cs46xx_proc_io_ops = {
diff --git a/sound/pci/emu10k1/emuproc.c b/sound/pci/emu10k1/emuproc.c
index 347b241..bc38dd4 100644
--- a/sound/pci/emu10k1/emuproc.c
+++ b/sound/pci/emu10k1/emuproc.c
@@ -346,10 +346,12 @@ static ssize_t snd_emu10k1_fx8010_read(struct snd_info_entry *entry,
struct file *file, char __user *buf,
size_t count, loff_t pos)
{
- long size;
struct snd_emu10k1 *emu = entry->private_data;
unsigned int offset;
int tram_addr = 0;
+ unsigned int *tmp;
+ long res;
+ unsigned int idx;
if (!strcmp(entry->name, "fx8010_tram_addr")) {
offset = TANKMEMADDRREGBASE;
@@ -361,30 +363,25 @@ static ssize_t snd_emu10k1_fx8010_read(struct snd_info_entry *entry,
} else {
offset = emu->audigy ? A_FXGPREGBASE : FXGPREGBASE;
}
- size = count;
- if (pos + size > entry->size)
- size = (long)entry->size - pos;
- if (size > 0) {
- unsigned int *tmp;
- long res;
- unsigned int idx;
- if ((tmp = kmalloc(size + 8, GFP_KERNEL)) == NULL)
- return -ENOMEM;
- for (idx = 0; idx < ((pos & 3) + size + 3) >> 2; idx++)
- if (tram_addr && emu->audigy) {
- tmp[idx] = snd_emu10k1_ptr_read(emu, offset + idx + (pos >> 2), 0) >> 11;
- tmp[idx] |= snd_emu10k1_ptr_read(emu, 0x100 + idx + (pos >> 2), 0) << 20;
- } else
- tmp[idx] = snd_emu10k1_ptr_read(emu, offset + idx + (pos >> 2), 0);
- if (copy_to_user(buf, ((char *)tmp) + (pos & 3), size))
- res = -EFAULT;
- else {
- res = size;
+
+ tmp = kmalloc(count + 8, GFP_KERNEL);
+ if (!tmp)
+ return -ENOMEM;
+ for (idx = 0; idx < ((pos & 3) + count + 3) >> 2; idx++) {
+ unsigned int val;
+ val = snd_emu10k1_ptr_read(emu, offset + idx + (pos >> 2), 0);
+ if (tram_addr && emu->audigy) {
+ val >>= 11;
+ val |= snd_emu10k1_ptr_read(emu, 0x100 + idx + (pos >> 2), 0) << 20;
}
- kfree(tmp);
- return res;
+ tmp[idx] = val;
}
- return 0;
+ if (copy_to_user(buf, ((char *)tmp) + (pos & 3), count))
+ res = -EFAULT;
+ else
+ res = count;
+ kfree(tmp);
+ return res;
}
static void snd_emu10k1_proc_voices_read(struct snd_info_entry *entry,
diff --git a/sound/pci/mixart/mixart.c b/sound/pci/mixart/mixart.c
index b5df78b..be95e00 100644
--- a/sound/pci/mixart/mixart.c
+++ b/sound/pci/mixart/mixart.c
@@ -1161,13 +1161,7 @@ static ssize_t snd_mixart_BA0_read(struct snd_info_entry *entry,
size_t count, loff_t pos)
{
struct mixart_mgr *mgr = entry->private_data;
- unsigned long maxsize;
- if (pos >= MIXART_BA0_SIZE)
- return 0;
- maxsize = MIXART_BA0_SIZE - pos;
- if (count > maxsize)
- count = maxsize;
count = count & ~3; /* make sure the read size is a multiple of 4 bytes */
if (copy_to_user_fromio(buf, MIXART_MEM(mgr, pos), count))
return -EFAULT;
@@ -1183,13 +1177,7 @@ static ssize_t snd_mixart_BA1_read(struct snd_info_entry *entry,
size_t count, loff_t pos)
{
struct mixart_mgr *mgr = entry->private_data;
- unsigned long maxsize;
- if (pos > MIXART_BA1_SIZE)
- return 0;
- maxsize = MIXART_BA1_SIZE - pos;
- if (count > maxsize)
- count = maxsize;
count = count & ~3; /* make sure the read size is a multiple of 4 bytes */
if (copy_to_user_fromio(buf, MIXART_REG(mgr, pos), count))
return -EFAULT;
--
1.7.0.4
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