Driver-Core: extend devnode callbacks to provide permissions
This allows subsytems to provide devtmpfs with non-default permissions
for the device node. Instead of the default mode of 0600, null, zero,
random, urandom, full, tty, ptmx now have a mode of 0666, which allows
non-privileged processes to access standard device nodes in case no
other userspace process applies the expected permissions.
This also fixes a wrong assignment in pktcdvd and a checkpatch.pl complain.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c
index fc93e2f..1573aeb 100644
--- a/drivers/char/hw_random/core.c
+++ b/drivers/char/hw_random/core.c
@@ -153,7 +153,7 @@
static struct miscdevice rng_miscdev = {
.minor = RNG_MISCDEV_MINOR,
.name = RNG_MODULE_NAME,
- .devnode = "hwrng",
+ .nodename = "hwrng",
.fops = &rng_chrdev_ops,
};
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 0491cdf..0aede1d 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -866,24 +866,25 @@
static const struct memdev {
const char *name;
+ mode_t mode;
const struct file_operations *fops;
struct backing_dev_info *dev_info;
} devlist[] = {
- [ 1] = { "mem", &mem_fops, &directly_mappable_cdev_bdi },
+ [1] = { "mem", 0, &mem_fops, &directly_mappable_cdev_bdi },
#ifdef CONFIG_DEVKMEM
- [ 2] = { "kmem", &kmem_fops, &directly_mappable_cdev_bdi },
+ [2] = { "kmem", 0, &kmem_fops, &directly_mappable_cdev_bdi },
#endif
- [ 3] = {"null", &null_fops, NULL },
+ [3] = { "null", 0666, &null_fops, NULL },
#ifdef CONFIG_DEVPORT
- [ 4] = { "port", &port_fops, NULL },
+ [4] = { "port", 0, &port_fops, NULL },
#endif
- [ 5] = { "zero", &zero_fops, &zero_bdi },
- [ 7] = { "full", &full_fops, NULL },
- [ 8] = { "random", &random_fops, NULL },
- [ 9] = { "urandom", &urandom_fops, NULL },
- [11] = { "kmsg", &kmsg_fops, NULL },
+ [5] = { "zero", 0666, &zero_fops, &zero_bdi },
+ [7] = { "full", 0666, &full_fops, NULL },
+ [8] = { "random", 0666, &random_fops, NULL },
+ [9] = { "urandom", 0666, &urandom_fops, NULL },
+ [11] = { "kmsg", 0, &kmsg_fops, NULL },
#ifdef CONFIG_CRASH_DUMP
- [12] = { "oldmem", &oldmem_fops, NULL },
+ [12] = { "oldmem", 0, &oldmem_fops, NULL },
#endif
};
@@ -920,6 +921,13 @@
.open = memory_open,
};
+static char *mem_devnode(struct device *dev, mode_t *mode)
+{
+ if (mode && devlist[MINOR(dev->devt)].mode)
+ *mode = devlist[MINOR(dev->devt)].mode;
+ return NULL;
+}
+
static struct class *mem_class;
static int __init chr_dev_init(void)
@@ -935,6 +943,7 @@
printk("unable to get major %d for memory devs\n", MEM_MAJOR);
mem_class = class_create(THIS_MODULE, "mem");
+ mem_class->devnode = mem_devnode;
for (minor = 1; minor < ARRAY_SIZE(devlist); minor++) {
if (!devlist[minor].name)
continue;
diff --git a/drivers/char/misc.c b/drivers/char/misc.c
index 62c99fa..1ee27cc 100644
--- a/drivers/char/misc.c
+++ b/drivers/char/misc.c
@@ -263,12 +263,14 @@
EXPORT_SYMBOL(misc_register);
EXPORT_SYMBOL(misc_deregister);
-static char *misc_nodename(struct device *dev)
+static char *misc_devnode(struct device *dev, mode_t *mode)
{
struct miscdevice *c = dev_get_drvdata(dev);
- if (c->devnode)
- return kstrdup(c->devnode, GFP_KERNEL);
+ if (mode && c->mode)
+ *mode = c->mode;
+ if (c->nodename)
+ return kstrdup(c->nodename, GFP_KERNEL);
return NULL;
}
@@ -287,7 +289,7 @@
err = -EIO;
if (register_chrdev(MISC_MAJOR,"misc",&misc_fops))
goto fail_printk;
- misc_class->nodename = misc_nodename;
+ misc_class->devnode = misc_devnode;
return 0;
fail_printk:
diff --git a/drivers/char/raw.c b/drivers/char/raw.c
index 40268db..64acd05 100644
--- a/drivers/char/raw.c
+++ b/drivers/char/raw.c
@@ -261,7 +261,7 @@
static struct cdev raw_cdev;
-static char *raw_nodename(struct device *dev)
+static char *raw_devnode(struct device *dev, mode_t *mode)
{
return kasprintf(GFP_KERNEL, "raw/%s", dev_name(dev));
}
@@ -289,7 +289,7 @@
ret = PTR_ERR(raw_class);
goto error_region;
}
- raw_class->nodename = raw_nodename;
+ raw_class->devnode = raw_devnode;
device_create(raw_class, NULL, MKDEV(RAW_MAJOR, 0), NULL, "rawctl");
return 0;
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index a3afa0c..c70d9da 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -3056,11 +3056,22 @@
}
}
+static char *tty_devnode(struct device *dev, mode_t *mode)
+{
+ if (!mode)
+ return NULL;
+ if (dev->devt == MKDEV(TTYAUX_MAJOR, 0) ||
+ dev->devt == MKDEV(TTYAUX_MAJOR, 2))
+ *mode = 0666;
+ return NULL;
+}
+
static int __init tty_class_init(void)
{
tty_class = class_create(THIS_MODULE, "tty");
if (IS_ERR(tty_class))
return PTR_ERR(tty_class);
+ tty_class->devnode = tty_devnode;
return 0;
}
