diff options
author | Grazvydas Ignotas <notasas@gmail.com> | 2015-02-12 15:00:19 -0800 |
---|---|---|
committer | Zefan Li <lizefan@huawei.com> | 2015-06-19 11:40:16 +0800 |
commit | 601391cbb6334533d6fde4e81f40b53b5f85d73b (patch) | |
tree | d28f27c9c425c144eecf52ef793a704d1908c03b /mm | |
parent | 0484ec07d706577b751c58dbb4df662761d098c6 (diff) |
mm/memory.c: actually remap enough memory
commit 9cb12d7b4ccaa976f97ce0c5fd0f1b6a83bc2a75 upstream.
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>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Zefan Li <lizefan@huawei.com>
Diffstat (limited to 'mm')
-rw-r--r-- | mm/memory.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/memory.c b/mm/memory.c index 45cd14f0c7bf..02aef93416f2 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3845,7 +3845,7 @@ 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); else |