From e454cea20bdcff10ee698d11b8882662a0153a47 Mon Sep 17 00:00:00 2001 From: Kay Sievers Date: Fri, 18 Sep 2009 23:01:12 +0200 Subject: 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 Signed-off-by: Greg Kroah-Hartman --- drivers/char/hw_random/core.c | 2 +- drivers/char/mem.c | 29 +++++++++++++++++++---------- drivers/char/misc.c | 10 ++++++---- drivers/char/raw.c | 4 ++-- drivers/char/tty_io.c | 11 +++++++++++ 5 files changed, 39 insertions(+), 17 deletions(-) (limited to 'drivers/char') diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index fc93e2fc7c71..1573aebd54b5 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -153,7 +153,7 @@ static const struct file_operations rng_chrdev_ops = { 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 0491cdf63f2a..0aede1d6a9ea 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -866,24 +866,25 @@ static const struct file_operations kmsg_fops = { 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 @@ static const struct file_operations memory_fops = { .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 @@ static int __init chr_dev_init(void) 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 62c99fa59e2b..1ee27cc23426 100644 --- a/drivers/char/misc.c +++ b/drivers/char/misc.c @@ -263,12 +263,14 @@ int misc_deregister(struct miscdevice *misc) 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 @@ static int __init misc_init(void) 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 40268db02e22..64acd05f71c8 100644 --- a/drivers/char/raw.c +++ b/drivers/char/raw.c @@ -261,7 +261,7 @@ static const struct file_operations raw_ctl_fops = { 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 @@ static int __init raw_init(void) 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 a3afa0c387cd..c70d9dabefae 100644 --- a/drivers/char/tty_io.c +++ b/drivers/char/tty_io.c @@ -3056,11 +3056,22 @@ void __init console_init(void) } } +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; } -- cgit v1.2.3