diff options
author | Grazvydas Ignotas <notasas@gmail.com> | 2015-02-12 15:00:19 -0800 |
---|---|---|
committer | Ben Hutchings <ben@decadent.org.uk> | 2015-05-09 23:16:17 +0100 |
commit | c8d452410c798d28ac96c3716b011d3d6b5d3ade (patch) | |
tree | 14c340229514d2a422e6dc5dda8da748d84563a1 /mm | |
parent | ab623fbc5a00f5525569e2c33b6b215e39a2453b (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: Ben Hutchings <ben@decadent.org.uk>
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 0a7bb38f4c98..452b8ba24741 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3831,7 +3831,7 @@ 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 |