[PATCH 0/9] misc: constify 'struct bin_attribute'

[PATCH 0/9] misc: constify 'struct bin_attribute'

[Thomas Weißschuh]

The sysfs core now allows instances of 'struct bin_attribute' to be
moved into read-only memory. Make use of that to protect them against
accidental or malicious modifications.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
Thomas Weißschuh (9):
      ocxl: Constify 'struct bin_attribute'
      cxl: Constify 'struct bin_attribute'
      misc: sram: constify 'struct bin_attribute'
      misc: c2port: Calculate bin_attribute size through group callback
      misc: c2port: Constify 'struct bin_attribute'
      misc: pch_phub: Constify 'struct bin_attribute'
      misc: eeprom/idt_89hpesx: Constify 'struct bin_attribute'
      misc: eeprom/max6875: Constify 'struct bin_attribute'
      misc: ds1682: Constify 'struct bin_attribute'

 drivers/misc/c2port/core.c        | 27 +++++++++++++++++++--------
 drivers/misc/cxl/sysfs.c          |  8 ++++----
 drivers/misc/ds1682.c             |  8 ++++----
 drivers/misc/eeprom/idt_89hpesx.c |  6 +++---
 drivers/misc/eeprom/max6875.c     |  4 ++--
 drivers/misc/ocxl/sysfs.c         |  4 ++--
 drivers/misc/pch_phub.c           |  8 ++++----
 drivers/misc/sram.c               |  8 ++++----
 8 files changed, 42 insertions(+), 31 deletions(-)
---
base-commit: 78d4f34e2115b517bcbfe7ec0d018bbbb6f9b0b8
change-id: 20241215-sysfs-const-bin_attr-misc-drivers-721114a2b3d3

Best regards,
-- 
Thomas Weißschuh <linux@weissschuh.net>

[PATCH 1/9] ocxl: Constify 'struct bin_attribute'

[Thomas Weißschuh]

The sysfs core now allows instances of 'struct bin_attribute' to be
moved into read-only memory. Make use of that to protect them against
accidental or malicious modifications.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 drivers/misc/ocxl/sysfs.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/misc/ocxl/sysfs.c b/drivers/misc/ocxl/sysfs.c
index 07520d6e6dc55702696b8656440914c379e6e27a..e849641687a005fec5eb7a6b2e96bc0e9d04dc05 100644
--- a/drivers/misc/ocxl/sysfs.c
+++ b/drivers/misc/ocxl/sysfs.c
@@ -94,7 +94,7 @@ static struct device_attribute afu_attrs[] = {
 };
 
 static ssize_t global_mmio_read(struct file *filp, struct kobject *kobj,
-				struct bin_attribute *bin_attr, char *buf,
+				const struct bin_attribute *bin_attr, char *buf,
 				loff_t off, size_t count)
 {
 	struct ocxl_afu *afu = to_afu(kobj_to_dev(kobj));
@@ -155,7 +155,7 @@ int ocxl_sysfs_register_afu(struct ocxl_file_info *info)
 	info->attr_global_mmio.attr.name = "global_mmio_area";
 	info->attr_global_mmio.attr.mode = 0600;
 	info->attr_global_mmio.size = info->afu->config.global_mmio_size;
-	info->attr_global_mmio.read = global_mmio_read;
+	info->attr_global_mmio.read_new = global_mmio_read;
 	info->attr_global_mmio.mmap = global_mmio_mmap;
 	rc = device_create_bin_file(&info->dev, &info->attr_global_mmio);
 	if (rc) {

-- 
2.47.1

[PATCH 2/9] cxl: Constify 'struct bin_attribute'

[Thomas Weißschuh]

The sysfs core now allows instances of 'struct bin_attribute' to be
moved into read-only memory. Make use of that to protect them against
accidental or malicious modifications.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 drivers/misc/cxl/sysfs.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/misc/cxl/sysfs.c b/drivers/misc/cxl/sysfs.c
index 409bd1c39663159a0d11c3ccba2aa5a8451baa34..b1fc6446bd4b7caa2f5c6e23e0aba5934caffd46 100644
--- a/drivers/misc/cxl/sysfs.c
+++ b/drivers/misc/cxl/sysfs.c
@@ -444,7 +444,7 @@ static ssize_t api_version_compatible_show(struct device *device,
 }
 
 static ssize_t afu_eb_read(struct file *filp, struct kobject *kobj,
-			       struct bin_attribute *bin_attr, char *buf,
+			       const struct bin_attribute *bin_attr, char *buf,
 			       loff_t off, size_t count)
 {
 	struct cxl_afu *afu = to_cxl_afu(kobj_to_dev(kobj));
@@ -538,7 +538,7 @@ static ssize_t class_show(struct kobject *kobj,
 }
 
 static ssize_t afu_read_config(struct file *filp, struct kobject *kobj,
-			       struct bin_attribute *bin_attr, char *buf,
+			       const struct bin_attribute *bin_attr, char *buf,
 			       loff_t off, size_t count)
 {
 	struct afu_config_record *cr = to_cr(kobj);
@@ -620,7 +620,7 @@ static struct afu_config_record *cxl_sysfs_afu_new_cr(struct cxl_afu *afu, int c
 	cr->config_attr.attr.name = "config";
 	cr->config_attr.attr.mode = S_IRUSR;
 	cr->config_attr.size = afu->crs_len;
-	cr->config_attr.read = afu_read_config;
+	cr->config_attr.read_new = afu_read_config;
 
 	rc = kobject_init_and_add(&cr->kobj, &afu_config_record_type,
 				  &afu->dev.kobj, "cr%i", cr->cr);
@@ -693,7 +693,7 @@ int cxl_sysfs_afu_add(struct cxl_afu *afu)
 		afu->attr_eb.attr.name = "afu_err_buff";
 		afu->attr_eb.attr.mode = S_IRUGO;
 		afu->attr_eb.size = afu->eb_len;
-		afu->attr_eb.read = afu_eb_read;
+		afu->attr_eb.read_new = afu_eb_read;
 
 		rc = device_create_bin_file(&afu->dev, &afu->attr_eb);
 		if (rc) {

-- 
2.47.1

[PATCH 3/9] misc: sram: constify 'struct bin_attribute'

[Thomas Weißschuh]

The sysfs core now allows instances of 'struct bin_attribute' to be
moved into read-only memory. Make use of that to protect them against
accidental or malicious modifications.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 drivers/misc/sram.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/misc/sram.c b/drivers/misc/sram.c
index e40b027a88e25209933a20dc9dbd7db29cb81ba5..e5069882457ef6ba5dc084d02994034dc39d24c6 100644
--- a/drivers/misc/sram.c
+++ b/drivers/misc/sram.c
@@ -23,7 +23,7 @@
 #define SRAM_GRANULARITY	32
 
 static ssize_t sram_read(struct file *filp, struct kobject *kobj,
-			 struct bin_attribute *attr,
+			 const struct bin_attribute *attr,
 			 char *buf, loff_t pos, size_t count)
 {
 	struct sram_partition *part;
@@ -38,7 +38,7 @@ static ssize_t sram_read(struct file *filp, struct kobject *kobj,
 }
 
 static ssize_t sram_write(struct file *filp, struct kobject *kobj,
-			  struct bin_attribute *attr,
+			  const struct bin_attribute *attr,
 			  char *buf, loff_t pos, size_t count)
 {
 	struct sram_partition *part;
@@ -83,8 +83,8 @@ static int sram_add_export(struct sram_dev *sram, struct sram_reserve *block,
 		return -ENOMEM;
 
 	part->battr.attr.mode = S_IRUSR | S_IWUSR;
-	part->battr.read = sram_read;
-	part->battr.write = sram_write;
+	part->battr.read_new = sram_read;
+	part->battr.write_new = sram_write;
 	part->battr.size = block->size;
 
 	return device_create_bin_file(sram->dev, &part->battr);

-- 
2.47.1

[PATCH 4/9] misc: c2port: Calculate bin_attribute size through group callback

[Thomas Weißschuh]

Modifying the size of the global bin_attribute instance can be racy.
Instead use the new .bin_size callback to do so safely.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 drivers/misc/c2port/core.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/drivers/misc/c2port/core.c b/drivers/misc/c2port/core.c
index 2bb1dd2511f9dd178b8c06baa460bb609f7f8fd7..5d6767b484c998b44a3c90c177d12028db1ea1af 100644
--- a/drivers/misc/c2port/core.c
+++ b/drivers/misc/c2port/core.c
@@ -874,9 +874,22 @@ static struct bin_attribute *c2port_bin_attrs[] = {
 	NULL,
 };
 
+static size_t c2port_bin_attr_size(struct kobject *kobj,
+				   const struct bin_attribute *attr,
+				   int i)
+{
+	struct c2port_device *c2dev = dev_get_drvdata(kobj_to_dev(kobj));
+
+	if (attr == &bin_attr_flash_data)
+		return c2dev->ops->blocks_num * c2dev->ops->block_size;
+
+	return attr->size;
+}
+
 static const struct attribute_group c2port_group = {
 	.attrs = c2port_attrs,
 	.bin_attrs = c2port_bin_attrs,
+	.bin_size = c2port_bin_attr_size,
 };
 
 static const struct attribute_group *c2port_groups[] = {
@@ -913,8 +926,6 @@ struct c2port_device *c2port_device_register(char *name,
 		goto error_idr_alloc;
 	c2dev->id = ret;
 
-	bin_attr_flash_data.size = ops->blocks_num * ops->block_size;
-
 	c2dev->dev = device_create(c2port_class, NULL, 0, c2dev,
 				   "c2port%d", c2dev->id);
 	if (IS_ERR(c2dev->dev)) {

-- 
2.47.1

[PATCH 5/9] misc: c2port: Constify 'struct bin_attribute'

[Thomas Weißschuh]

The sysfs core now allows instances of 'struct bin_attribute' to be
moved into read-only memory. Make use of that to protect them against
accidental or malicious modifications.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 drivers/misc/c2port/core.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/misc/c2port/core.c b/drivers/misc/c2port/core.c
index 5d6767b484c998b44a3c90c177d12028db1ea1af..eb780e635352f3a815e8d400d71c04b47507cd4b 100644
--- a/drivers/misc/c2port/core.c
+++ b/drivers/misc/c2port/core.c
@@ -714,7 +714,7 @@ static ssize_t __c2port_read_flash_data(struct c2port_device *dev,
 }
 
 static ssize_t c2port_read_flash_data(struct file *filp, struct kobject *kobj,
-				struct bin_attribute *attr,
+				const struct bin_attribute *attr,
 				char *buffer, loff_t offset, size_t count)
 {
 	struct c2port_device *c2dev = dev_get_drvdata(kobj_to_dev(kobj));
@@ -829,7 +829,7 @@ static ssize_t __c2port_write_flash_data(struct c2port_device *dev,
 }
 
 static ssize_t c2port_write_flash_data(struct file *filp, struct kobject *kobj,
-				struct bin_attribute *attr,
+				const struct bin_attribute *attr,
 				char *buffer, loff_t offset, size_t count)
 {
 	struct c2port_device *c2dev = dev_get_drvdata(kobj_to_dev(kobj));
@@ -849,8 +849,8 @@ static ssize_t c2port_write_flash_data(struct file *filp, struct kobject *kobj,
 	return ret;
 }
 /* size is computed at run-time */
-static BIN_ATTR(flash_data, 0644, c2port_read_flash_data,
-		c2port_write_flash_data, 0);
+static const BIN_ATTR(flash_data, 0644, c2port_read_flash_data,
+		      c2port_write_flash_data, 0);
 
 /*
  * Class attributes
@@ -869,7 +869,7 @@ static struct attribute *c2port_attrs[] = {
 	NULL,
 };
 
-static struct bin_attribute *c2port_bin_attrs[] = {
+static const struct bin_attribute *const c2port_bin_attrs[] = {
 	&bin_attr_flash_data,
 	NULL,
 };
@@ -888,7 +888,7 @@ static size_t c2port_bin_attr_size(struct kobject *kobj,
 
 static const struct attribute_group c2port_group = {
 	.attrs = c2port_attrs,
-	.bin_attrs = c2port_bin_attrs,
+	.bin_attrs_new = c2port_bin_attrs,
 	.bin_size = c2port_bin_attr_size,
 };
 

-- 
2.47.1

[PATCH 6/9] misc: pch_phub: Constify 'struct bin_attribute'

[Thomas Weißschuh]

The sysfs core now allows instances of 'struct bin_attribute' to be
moved into read-only memory. Make use of that to protect them against
accidental or malicious modifications.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 drivers/misc/pch_phub.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/misc/pch_phub.c b/drivers/misc/pch_phub.c
index 8d2b7135738ed5543138f2249d2379a10113b410..6121c0940cd148d48b8d574065c50703b6a301d7 100644
--- a/drivers/misc/pch_phub.c
+++ b/drivers/misc/pch_phub.c
@@ -483,7 +483,7 @@ static int pch_phub_write_gbe_mac_addr(struct pch_phub_reg *chip, u8 *data)
 }
 
 static ssize_t pch_phub_bin_read(struct file *filp, struct kobject *kobj,
-				 struct bin_attribute *attr, char *buf,
+				 const struct bin_attribute *attr, char *buf,
 				 loff_t off, size_t count)
 {
 	unsigned int rom_signature;
@@ -553,7 +553,7 @@ static ssize_t pch_phub_bin_read(struct file *filp, struct kobject *kobj,
 }
 
 static ssize_t pch_phub_bin_write(struct file *filp, struct kobject *kobj,
-				  struct bin_attribute *attr,
+				  const struct bin_attribute *attr,
 				  char *buf, loff_t off, size_t count)
 {
 	int err;
@@ -655,8 +655,8 @@ static const struct bin_attribute pch_bin_attr = {
 		.mode = S_IRUGO | S_IWUSR,
 	},
 	.size = PCH_PHUB_OROM_SIZE + 1,
-	.read = pch_phub_bin_read,
-	.write = pch_phub_bin_write,
+	.read_new = pch_phub_bin_read,
+	.write_new = pch_phub_bin_write,
 };
 
 static int pch_phub_probe(struct pci_dev *pdev,

-- 
2.47.1

[PATCH 7/9] misc: eeprom/idt_89hpesx: Constify 'struct bin_attribute'

[Thomas Weißschuh]

The sysfs core now allows instances of 'struct bin_attribute' to be
moved into read-only memory. Make use of that to protect them against
accidental or malicious modifications.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 drivers/misc/eeprom/idt_89hpesx.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/misc/eeprom/idt_89hpesx.c b/drivers/misc/eeprom/idt_89hpesx.c
index 43421fe37d338874ff1c2949497c64ebf0143106..1fc632ebf22f560088084519e5ad8e8b37958368 100644
--- a/drivers/misc/eeprom/idt_89hpesx.c
+++ b/drivers/misc/eeprom/idt_89hpesx.c
@@ -847,7 +847,7 @@ static int idt_csr_read(struct idt_89hpesx_dev *pdev, u16 csraddr, u32 *data)
  * @count:	Number of bytes to write
  */
 static ssize_t eeprom_write(struct file *filp, struct kobject *kobj,
-			    struct bin_attribute *attr,
+			    const struct bin_attribute *attr,
 			    char *buf, loff_t off, size_t count)
 {
 	struct idt_89hpesx_dev *pdev;
@@ -871,7 +871,7 @@ static ssize_t eeprom_write(struct file *filp, struct kobject *kobj,
  * @count:	Number of bytes to write
  */
 static ssize_t eeprom_read(struct file *filp, struct kobject *kobj,
-			   struct bin_attribute *attr,
+			   const struct bin_attribute *attr,
 			   char *buf, loff_t off, size_t count)
 {
 	struct idt_89hpesx_dev *pdev;
@@ -1017,7 +1017,7 @@ static ssize_t idt_dbgfs_csr_read(struct file *filep, char __user *ubuf,
  * NOTE Size will be changed in compliance with OF node. EEPROM attribute will
  * be read-only as well if the corresponding flag is specified in OF node.
  */
-static BIN_ATTR_RW(eeprom, EEPROM_DEF_SIZE);
+static const BIN_ATTR_RW(eeprom, EEPROM_DEF_SIZE);
 
 /*
  * csr_dbgfs_ops - CSR debugfs-node read/write operations

-- 
2.47.1

[PATCH 8/9] misc: eeprom/max6875: Constify 'struct bin_attribute'

[Thomas Weißschuh]

The sysfs core now allows instances of 'struct bin_attribute' to be
moved into read-only memory. Make use of that to protect them against
accidental or malicious modifications.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 drivers/misc/eeprom/max6875.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/misc/eeprom/max6875.c b/drivers/misc/eeprom/max6875.c
index 6fab2ffa736b741593931c413f230d7c43b5b8dd..1c36ad153e783ead6ba2481c64838390f0bb05f4 100644
--- a/drivers/misc/eeprom/max6875.c
+++ b/drivers/misc/eeprom/max6875.c
@@ -104,7 +104,7 @@ static void max6875_update_slice(struct i2c_client *client, int slice)
 }
 
 static ssize_t max6875_read(struct file *filp, struct kobject *kobj,
-			    struct bin_attribute *bin_attr,
+			    const struct bin_attribute *bin_attr,
 			    char *buf, loff_t off, size_t count)
 {
 	struct i2c_client *client = kobj_to_i2c_client(kobj);
@@ -127,7 +127,7 @@ static const struct bin_attribute user_eeprom_attr = {
 		.mode = S_IRUGO,
 	},
 	.size = USER_EEPROM_SIZE,
-	.read = max6875_read,
+	.read_new = max6875_read,
 };
 
 static int max6875_probe(struct i2c_client *client)

-- 
2.47.1

[PATCH 9/9] misc: ds1682: Constify 'struct bin_attribute'

[Thomas Weißschuh]

The sysfs core now allows instances of 'struct bin_attribute' to be
moved into read-only memory. Make use of that to protect them against
accidental or malicious modifications.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 drivers/misc/ds1682.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/misc/ds1682.c b/drivers/misc/ds1682.c
index 4175df7ef0111f69ed8d4229b7ab50a3c3d7ad12..5d5a70a62e98b6691aac1c0f9142d39555ba4f8c 100644
--- a/drivers/misc/ds1682.c
+++ b/drivers/misc/ds1682.c
@@ -154,7 +154,7 @@ static const struct attribute_group ds1682_group = {
  * User data attribute
  */
 static ssize_t ds1682_eeprom_read(struct file *filp, struct kobject *kobj,
-				  struct bin_attribute *attr,
+				  const struct bin_attribute *attr,
 				  char *buf, loff_t off, size_t count)
 {
 	struct i2c_client *client = kobj_to_i2c_client(kobj);
@@ -172,7 +172,7 @@ static ssize_t ds1682_eeprom_read(struct file *filp, struct kobject *kobj,
 }
 
 static ssize_t ds1682_eeprom_write(struct file *filp, struct kobject *kobj,
-				   struct bin_attribute *attr,
+				   const struct bin_attribute *attr,
 				   char *buf, loff_t off, size_t count)
 {
 	struct i2c_client *client = kobj_to_i2c_client(kobj);
@@ -194,8 +194,8 @@ static const struct bin_attribute ds1682_eeprom_attr = {
 		.mode = S_IRUGO | S_IWUSR,
 	},
 	.size = DS1682_EEPROM_SIZE,
-	.read = ds1682_eeprom_read,
-	.write = ds1682_eeprom_write,
+	.read_new = ds1682_eeprom_read,
+	.write_new = ds1682_eeprom_write,
 };
 
 static int ds1682_nvmem_read(void *priv, unsigned int offset, void *val,

-- 
2.47.1

Re: [PATCH 2/9] cxl: Constify 'struct bin_attribute'

[Andrew Donnellan]

On Mon, 2024-12-16 at 12:32 +0100, Thomas Weißschuh wrote:
> The sysfs core now allows instances of 'struct bin_attribute' to be
> moved into read-only memory. Make use of that to protect them against
> accidental or malicious modifications.
> 
> Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>

Acked-by: Andrew Donnellan <ajd@linux.ibm.com>

noting that we're hoping to remove this driver shortly.


-- 
Andrew Donnellan    OzLabs, ADL Canberra
ajd@linux.ibm.com   IBM Australia Limited

Re: [PATCH 1/9] ocxl: Constify 'struct bin_attribute'

[Andrew Donnellan]

On Mon, 2024-12-16 at 12:32 +0100, Thomas Weißschuh wrote:
> The sysfs core now allows instances of 'struct bin_attribute' to be
> moved into read-only memory. Make use of that to protect them against
> accidental or malicious modifications.
> 
> Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>

Acked-by: Andrew Donnellan <ajd@linux.ibm.com>


-- 
Andrew Donnellan    OzLabs, ADL Canberra
ajd@linux.ibm.com   IBM Australia Limited