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: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Ananth 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: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Oleg Nesterov 2012-06-15 17:43:47 +02:00 committed by Ingo Molnar
parent fc36f59565
commit eb2bf57bee
1 changed files with 0 additions and 5 deletions

View File

@ -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 @@ retry:
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)