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	mm/mprotect: replace can_modify_mm with can_modify_vma
Avoid taking an extra trip down the mmap tree by checking the vmas directly. mprotect (per POSIX) tolerates partial failure. Link: https://lkml.kernel.org/r/20240817-mseal-depessimize-v3-3-d8d2e037df30@gmail.com Signed-off-by: Pedro Falcato <pedro.falcato@gmail.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Jeff Xu <jeffxu@chromium.org> Cc: Kees Cook <kees@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Shuah Khan <shuah@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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					 1 changed files with 3 additions and 9 deletions
				
			
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					@ -611,6 +611,9 @@ mprotect_fixup(struct vma_iterator *vmi, struct mmu_gather *tlb,
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	unsigned long charged = 0;
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						unsigned long charged = 0;
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	int error;
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						int error;
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						if (!can_modify_vma(vma))
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							return -EPERM;
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	if (newflags == oldflags) {
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						if (newflags == oldflags) {
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		*pprev = vma;
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							*pprev = vma;
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		return 0;
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							return 0;
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					@ -769,15 +772,6 @@ static int do_mprotect_pkey(unsigned long start, size_t len,
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		}
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							}
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	}
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						}
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	/*
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	 * checking if memory is sealed.
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	 * can_modify_mm assumes we have acquired the lock on MM.
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	 */
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	if (unlikely(!can_modify_mm(current->mm, start, end))) {
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		error = -EPERM;
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		goto out;
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	}
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	prev = vma_prev(&vmi);
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						prev = vma_prev(&vmi);
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	if (start > vma->vm_start)
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						if (start > vma->vm_start)
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		prev = vma;
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							prev = vma;
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