fs/kernel_read_file: Remove redundant size argument
In preparation for refactoring kernel_read_file*(), remove the redundant
"size" argument which is not needed: it can be included in the return
code, with callers adjusted. (VFS reads already cannot be larger than
INT_MAX.)
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Link: https://lore.kernel.org/r/20201002173828.2099543-6-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/fs/kernel_read_file.c b/fs/kernel_read_file.c
index 54d972d..dc28a8d 100644
--- a/fs/kernel_read_file.c
+++ b/fs/kernel_read_file.c
@@ -5,7 +5,7 @@
#include <linux/security.h>
#include <linux/vmalloc.h>
-int kernel_read_file(struct file *file, void **buf, loff_t *size,
+int kernel_read_file(struct file *file, void **buf,
loff_t max_size, enum kernel_read_file_id id)
{
loff_t i_size, pos;
@@ -29,7 +29,7 @@ int kernel_read_file(struct file *file, void **buf, loff_t *size,
ret = -EINVAL;
goto out;
}
- if (i_size > SIZE_MAX || (max_size > 0 && i_size > max_size)) {
+ if (i_size > INT_MAX || (max_size > 0 && i_size > max_size)) {
ret = -EFBIG;
goto out;
}
@@ -59,8 +59,6 @@ int kernel_read_file(struct file *file, void **buf, loff_t *size,
}
ret = security_kernel_post_read_file(file, *buf, i_size, id);
- if (!ret)
- *size = pos;
out_free:
if (ret < 0) {
@@ -72,11 +70,11 @@ int kernel_read_file(struct file *file, void **buf, loff_t *size,
out:
allow_write_access(file);
- return ret;
+ return ret == 0 ? pos : ret;
}
EXPORT_SYMBOL_GPL(kernel_read_file);
-int kernel_read_file_from_path(const char *path, void **buf, loff_t *size,
+int kernel_read_file_from_path(const char *path, void **buf,
loff_t max_size, enum kernel_read_file_id id)
{
struct file *file;
@@ -89,14 +87,14 @@ int kernel_read_file_from_path(const char *path, void **buf, loff_t *size,
if (IS_ERR(file))
return PTR_ERR(file);
- ret = kernel_read_file(file, buf, size, max_size, id);
+ ret = kernel_read_file(file, buf, max_size, id);
fput(file);
return ret;
}
EXPORT_SYMBOL_GPL(kernel_read_file_from_path);
int kernel_read_file_from_path_initns(const char *path, void **buf,
- loff_t *size, loff_t max_size,
+ loff_t max_size,
enum kernel_read_file_id id)
{
struct file *file;
@@ -115,13 +113,13 @@ int kernel_read_file_from_path_initns(const char *path, void **buf,
if (IS_ERR(file))
return PTR_ERR(file);
- ret = kernel_read_file(file, buf, size, max_size, id);
+ ret = kernel_read_file(file, buf, max_size, id);
fput(file);
return ret;
}
EXPORT_SYMBOL_GPL(kernel_read_file_from_path_initns);
-int kernel_read_file_from_fd(int fd, void **buf, loff_t *size, loff_t max_size,
+int kernel_read_file_from_fd(int fd, void **buf, loff_t max_size,
enum kernel_read_file_id id)
{
struct fd f = fdget(fd);
@@ -130,7 +128,7 @@ int kernel_read_file_from_fd(int fd, void **buf, loff_t *size, loff_t max_size,
if (!f.file)
goto out;
- ret = kernel_read_file(f.file, buf, size, max_size, id);
+ ret = kernel_read_file(f.file, buf, max_size, id);
out:
fdput(f);
return ret;