path: root/mm
diff options
authorGrazvydas Ignotas <notasas@gmail.com>2015-02-12 23:00:19 (GMT)
committerLinus Torvalds <torvalds@linux-foundation.org>2015-02-13 02:54:11 (GMT)
commit9cb12d7b4ccaa976f97ce0c5fd0f1b6a83bc2a75 (patch)
treee0a8e02b5cb9296e057f68b4cb8a53398345e189 /mm
parent8f4ab07f4bf1b1069c01b7c6758a7d444406996b (diff)
mm/memory.c: actually remap enough memory
For whatever reason, generic_access_phys() only remaps one page, but actually allows to access arbitrary size. It's quite easy to trigger large reads, like printing out large structure with gdb, which leads to a crash. Fix it by remapping correct size. Fixes: 28b2ee20c7cb ("access_process_vm device memory infrastructure") Signed-off-by: Grazvydas Ignotas <notasas@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/memory.c b/mm/memory.c
index f7886ab..9927532 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3462,7 +3462,7 @@ int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
if (follow_phys(vma, addr, write, &prot, &phys_addr))
return -EINVAL;
- maddr = ioremap_prot(phys_addr, PAGE_SIZE, prot);
+ maddr = ioremap_prot(phys_addr, PAGE_ALIGN(len + offset), prot);
if (write)
memcpy_toio(maddr + offset, buf, len);

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