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Commit eb2bf57b authored by Oleg Nesterov's avatar Oleg Nesterov Committed by Ingo Molnar
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uprobes: No need to re-check vma_address() in write_opcode() 



write_opcode() is called by register_for_each_vma() and
uprobe_mmap() paths. In both cases the caller has already
verified this vaddr under mmap_sem, no need to re-check.

Note also that this check is wrong anyway, we should not
truncate loff_t returned by vma_address() if we do not trust
this mapping.

Signed-off-by: default avatarOleg Nesterov <oleg@redhat.com>
Acked-by: default avatarSrikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: default avatarAnanth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154347.GA9604@redhat.com


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent fc36f595

kernel/events/uprobes.c

+0 −5
Original line number Diff line number Diff line
@@ -211,7 +211,6 @@ static int write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm, 
	struct vm_area_struct *vma;

	struct uprobe *uprobe;

	unsigned long pgoff;

	loff_t addr;

	int ret;

retry:

	/* Read the page with vaddr into memory */
@@ -235,10 +234,6 @@ static int write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm, 
	if (mapping != vma->vm_file->f_mapping)

		goto put_out;



	addr = vma_address(vma, uprobe->offset);

	if (vaddr != (unsigned long)addr)

		goto put_out;



	ret = -ENOMEM;

	new_page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, vaddr);

	if (!new_page)