Re: [RFC PATCH v5 2/4] mseal: add mseal syscall

[Matthew Wilcox]

On Tue, Jan 09, 2024 at 03:45:40PM +0000, jeffxu@xxxxxxxxxxxx wrote:
> +extern bool can_modify_mm(struct mm_struct *mm, unsigned long start,
> +		unsigned long end);
> +extern bool can_modify_mm_madv(struct mm_struct *mm, unsigned long start,
> +		unsigned long end, int behavior);

unnecessary use of extern.

> +static inline unsigned long get_mmap_seals(unsigned long prot,
> +	unsigned long flags)

needs more than one tab indent so it doesn't look like part of the body.

> +{
> +	unsigned long vm_seals;
> +
> +	if (prot & PROT_SEAL)
> +		vm_seals = VM_SEALED | VM_SEALABLE;
> +	else
> +		vm_seals = (flags & MAP_SEALABLE) ? VM_SEALABLE:0;

need spaces around the :

> +++ b/include/uapi/asm-generic/mman-common.h
> @@ -17,6 +17,11 @@
>  #define PROT_GROWSDOWN	0x01000000	/* mprotect flag: extend change to start of growsdown vma */
>  #define PROT_GROWSUP	0x02000000	/* mprotect flag: extend change to end of growsup vma */
>  
> +/*
> + * The PROT_SEAL defines memory sealing in the prot argument of mmap().
> + */
> +#define PROT_SEAL	_BITUL(26)	/* 0x04000000 */

why not follow the existing style?

> +static inline void set_vma_sealed(struct vm_area_struct *vma)
> +{
> +	vma->__vm_flags |= VM_SEALED;
> +}

uhh ... vm_flags_set() ?