diff options
| -rw-r--r-- | fs/read_write.c | 17 |
1 files changed, 9 insertions, 8 deletions
diff --git a/fs/read_write.c b/fs/read_write.c index 8f9fc05990ae..5110cd1e6e27 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -499,6 +499,7 @@ static ssize_t __vfs_write(struct file *file, const char __user *p, return -EINVAL; } +/* caller is responsible for file_start_write/file_end_write */ ssize_t __kernel_write(struct file *file, const void *buf, size_t count, loff_t *pos) { mm_segment_t old_fs; @@ -528,16 +529,16 @@ ssize_t __kernel_write(struct file *file, const void *buf, size_t count, loff_t ssize_t kernel_write(struct file *file, const void *buf, size_t count, loff_t *pos) { - mm_segment_t old_fs; - ssize_t res; + ssize_t ret; - old_fs = get_fs(); - set_fs(KERNEL_DS); - /* The cast to a user pointer is valid due to the set_fs() */ - res = vfs_write(file, (__force const char __user *)buf, count, pos); - set_fs(old_fs); + ret = rw_verify_area(WRITE, file, pos, count); + if (ret) + return ret; - return res; + file_start_write(file); + ret = __kernel_write(file, buf, count, pos); + file_end_write(file); + return ret; } EXPORT_SYMBOL(kernel_write); |