diff options
| -rw-r--r-- | fs/char_dev.c | 17 | ||||
| -rw-r--r-- | fs/proc/devices.c | 8 | ||||
| -rw-r--r-- | include/linux/fs.h | 2 |
3 files changed, 18 insertions, 9 deletions
diff --git a/fs/char_dev.c b/fs/char_dev.c index c9d18362e89d..ebcc8fb3fa66 100644 --- a/fs/char_dev.c +++ b/fs/char_dev.c @@ -28,6 +28,8 @@ static struct kobj_map *cdev_map; static DEFINE_MUTEX(chrdevs_lock); +#define CHRDEV_MAJOR_HASH_SIZE 255 + static struct char_device_struct { struct char_device_struct *next; unsigned int major; @@ -49,12 +51,12 @@ void chrdev_show(struct seq_file *f, off_t offset) { struct char_device_struct *cd; - if (offset < CHRDEV_MAJOR_HASH_SIZE) { - mutex_lock(&chrdevs_lock); - for (cd = chrdevs[offset]; cd; cd = cd->next) + mutex_lock(&chrdevs_lock); + for (cd = chrdevs[major_to_index(offset)]; cd; cd = cd->next) { + if (cd->major == offset) seq_printf(f, "%3d %s\n", cd->major, cd->name); - mutex_unlock(&chrdevs_lock); } + mutex_unlock(&chrdevs_lock); } #endif /* CONFIG_PROC_FS */ @@ -117,6 +119,13 @@ __register_chrdev_region(unsigned int major, unsigned int baseminor, major = ret; } + if (major >= CHRDEV_MAJOR_MAX) { + pr_err("CHRDEV \"%s\" major requested (%d) is greater than the maximum (%d)\n", + name, major, CHRDEV_MAJOR_MAX); + ret = -EINVAL; + goto out; + } + cd->major = major; cd->baseminor = baseminor; cd->minorct = minorct; diff --git a/fs/proc/devices.c b/fs/proc/devices.c index 50493edc30e5..d196e22c4f1c 100644 --- a/fs/proc/devices.c +++ b/fs/proc/devices.c @@ -7,14 +7,14 @@ static int devinfo_show(struct seq_file *f, void *v) { int i = *(loff_t *) v; - if (i < CHRDEV_MAJOR_HASH_SIZE) { + if (i < CHRDEV_MAJOR_MAX) { if (i == 0) seq_puts(f, "Character devices:\n"); chrdev_show(f, i); } #ifdef CONFIG_BLOCK else { - i -= CHRDEV_MAJOR_HASH_SIZE; + i -= CHRDEV_MAJOR_MAX; if (i == 0) seq_puts(f, "\nBlock devices:\n"); blkdev_show(f, i); @@ -25,7 +25,7 @@ static int devinfo_show(struct seq_file *f, void *v) static void *devinfo_start(struct seq_file *f, loff_t *pos) { - if (*pos < (BLKDEV_MAJOR_HASH_SIZE + CHRDEV_MAJOR_HASH_SIZE)) + if (*pos < (BLKDEV_MAJOR_HASH_SIZE + CHRDEV_MAJOR_MAX)) return pos; return NULL; } @@ -33,7 +33,7 @@ static void *devinfo_start(struct seq_file *f, loff_t *pos) static void *devinfo_next(struct seq_file *f, void *v, loff_t *pos) { (*pos)++; - if (*pos >= (BLKDEV_MAJOR_HASH_SIZE + CHRDEV_MAJOR_HASH_SIZE)) + if (*pos >= (BLKDEV_MAJOR_HASH_SIZE + CHRDEV_MAJOR_MAX)) return NULL; return pos; } diff --git a/include/linux/fs.h b/include/linux/fs.h index 1773dcf1e318..b07433c335ca 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2470,7 +2470,7 @@ static inline void bd_unlink_disk_holder(struct block_device *bdev, #endif /* fs/char_dev.c */ -#define CHRDEV_MAJOR_HASH_SIZE 255 +#define CHRDEV_MAJOR_MAX 512 /* Marks the bottom of the first segment of free char majors */ #define CHRDEV_MAJOR_DYN_END 234 /* Marks the top and bottom of the second segment of free char majors */ |