diff options
Diffstat (limited to 'fs')
-rw-r--r-- | fs/exec.c | 92 |
1 files changed, 92 insertions, 0 deletions
@@ -56,6 +56,7 @@ #include <linux/pipe_fs_i.h> #include <linux/oom.h> #include <linux/compat.h> +#include <linux/vmalloc.h> #include <asm/uaccess.h> #include <asm/mmu_context.h> @@ -831,6 +832,97 @@ int kernel_read(struct file *file, loff_t offset, EXPORT_SYMBOL(kernel_read); +int kernel_read_file(struct file *file, void **buf, loff_t *size, + loff_t max_size, enum kernel_read_file_id id) +{ + loff_t i_size, pos; + ssize_t bytes = 0; + int ret; + + if (!S_ISREG(file_inode(file)->i_mode) || max_size < 0) + return -EINVAL; + + ret = security_kernel_read_file(file, id); + if (ret) + return ret; + + i_size = i_size_read(file_inode(file)); + if (max_size > 0 && i_size > max_size) + return -EFBIG; + if (i_size <= 0) + return -EINVAL; + + *buf = vmalloc(i_size); + if (!*buf) + return -ENOMEM; + + pos = 0; + while (pos < i_size) { + bytes = kernel_read(file, pos, (char *)(*buf) + pos, + i_size - pos); + if (bytes < 0) { + ret = bytes; + goto out; + } + + if (bytes == 0) + break; + pos += bytes; + } + + if (pos != i_size) { + ret = -EIO; + goto out; + } + + ret = security_kernel_post_read_file(file, *buf, i_size, id); + if (!ret) + *size = pos; + +out: + if (ret < 0) { + vfree(*buf); + *buf = NULL; + } + return ret; +} +EXPORT_SYMBOL_GPL(kernel_read_file); + +int kernel_read_file_from_path(char *path, void **buf, loff_t *size, + loff_t max_size, enum kernel_read_file_id id) +{ + struct file *file; + int ret; + + if (!path || !*path) + return -EINVAL; + + file = filp_open(path, O_RDONLY, 0); + if (IS_ERR(file)) + return PTR_ERR(file); + + ret = kernel_read_file(file, buf, size, max_size, id); + fput(file); + return ret; +} +EXPORT_SYMBOL_GPL(kernel_read_file_from_path); + +int kernel_read_file_from_fd(int fd, void **buf, loff_t *size, loff_t max_size, + enum kernel_read_file_id id) +{ + struct fd f = fdget(fd); + int ret = -EBADF; + + if (!f.file) + goto out; + + ret = kernel_read_file(f.file, buf, size, max_size, id); +out: + fdput(f); + return ret; +} +EXPORT_SYMBOL_GPL(kernel_read_file_from_fd); + ssize_t read_code(struct file *file, unsigned long addr, loff_t pos, size_t len) { ssize_t res = vfs_read(file, (void __user *)addr, len, &pos); |