mm: fix overflow in vm_map_ram()
authorGuillermo Julián Moreno <guillermo.julian@naudit.es>
Fri, 3 Jun 2016 21:55:33 +0000 (14:55 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 3 Jun 2016 22:06:22 +0000 (15:06 -0700)
commit65ee03c4b9f89e1b088defd97273be6da169d798
treeca5bd05b3bc29cf2a5a07f083fd80221049aa06e
parent4340fa55298d17049e71c7a34e04647379c269f3
mm: fix overflow in vm_map_ram()

When remapping pages accounting for 4G or more memory space, the
operation 'count << PAGE_SHIFT' overflows as it is performed on an
integer.  Solution: cast before doing the bitshift.

[akpm@linux-foundation.org: fix vm_unmap_ram() also]
[akpm@linux-foundation.org: fix vmap() as well, per Guillermo]
Link: http://lkml.kernel.org/r/etPan.57175fb3.7a271c6b.2bd@naudit.es
Signed-off-by: Guillermo Julián Moreno <guillermo.julian@naudit.es>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/vmalloc.c