2024-02-11 01:53:25

by Lenko Donchev

Subject: [PATCH] fs/ntfs3: use kcalloc() instead of kzalloc()

We are trying to get rid of all multiplications from allocation
functions to prevent integer overflows[1]. Here the multiplication is
obviously safe, but using kcalloc() is more appropriate and improves
readability. This patch has no effect on runtime behavior.

Link: https://github.com/KSPP/linux/issues/162 [1]
Link: https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [2]

Signed-off-by: Lenko Donchev <[email protected]>
---
fs/ntfs3/frecord.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ntfs3/frecord.c b/fs/ntfs3/frecord.c
index 3b42938a9d3b..d435446537ca 100644
--- a/fs/ntfs3/frecord.c
+++ b/fs/ntfs3/frecord.c
@@ -2636,7 +2636,7 @@ int ni_read_frame(struct ntfs_inode *ni, u64 frame_vbo, struct page **pages,
goto out1;
}

- pages_disk = kzalloc(npages_disk * sizeof(struct page *), GFP_NOFS);
+ pages_disk = kcalloc(npages_disk, sizeof(struct page *), GFP_NOFS);
if (!pages_disk) {
err = -ENOMEM;
goto out2;
--
2.43.0

2024-02-11 04:32:09

by Gustavo A. R. Silva

Subject: Re: [PATCH] fs/ntfs3: use kcalloc() instead of kzalloc()

On 2/10/24 19:53, Lenko Donchev wrote:
> We are trying to get rid of all multiplications from allocation
> functions to prevent integer overflows[1]. Here the multiplication is
> obviously safe, but using kcalloc() is more appropriate and improves
> readability. This patch has no effect on runtime behavior.
>
> Link: https://github.com/KSPP/linux/issues/162 [1]
> Link: https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [2]
>
> Signed-off-by: Lenko Donchev <[email protected]>
> ---
> fs/ntfs3/frecord.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/ntfs3/frecord.c b/fs/ntfs3/frecord.c
> index 3b42938a9d3b..d435446537ca 100644
> --- a/fs/ntfs3/frecord.c
> +++ b/fs/ntfs3/frecord.c
> @@ -2636,7 +2636,7 @@ int ni_read_frame(struct ntfs_inode *ni, u64 frame_vbo, struct page **pages,
> goto out1;
> }
>
> - pages_disk = kzalloc(npages_disk * sizeof(struct page *), GFP_NOFS);
> + pages_disk = kcalloc(npages_disk, sizeof(struct page *), GFP_NOFS);

`sizeof(*pages_disk)` is preferable over `sizeof(struct page *)`

Thanks
--
Gustavo

> if (!pages_disk) {
> err = -ENOMEM;
> goto out2;