path: root/mm
diff options
authorGrazvydas Ignotas <notasas@gmail.com>2015-02-12 15:00:19 -0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2015-03-18 13:22:28 +0100
commit9113c468b621ddb74f2395564720862faa3a083d (patch)
tree07106171f45b552a3db43a9792462529175186c9 /mm
parent2295074e4465734d4cb83cba15e055b4b2a87737 (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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'mm')
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/memory.c b/mm/memory.c
index 8b2d75f61b32..04232bb173f0 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4088,7 +4088,7 @@ 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);