diff options
| author | Clemens Ladisch <clemens@ladisch.de> | 2011-06-21 22:09:50 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-08-14 12:32:52 -0700 |
| commit | f982f91516fa4cfd9d20518833cd04ad714585be (patch) | |
| tree | 15c7992ad6e54fbda868a026afd5ecf98f9b1bca /lib/lru_cache.c | |
| parent | 97c24d1d455df17ca3ef281d1a290988f4686643 (diff) | |
mm: fix wrong vmap address calculations with odd NR_CPUS values
Commit db64fe02258f ("mm: rewrite vmap layer") introduced code that does
address calculations under the assumption that VMAP_BLOCK_SIZE is a
power of two. However, this might not be true if CONFIG_NR_CPUS is not
set to a power of two.
Wrong vmap_block index/offset values could lead to memory corruption.
However, this has never been observed in practice (or never been
diagnosed correctly); what caught this was the BUG_ON in vb_alloc() that
checks for inconsistent vmap_block indices.
To fix this, ensure that VMAP_BLOCK_SIZE always is a power of two.
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=31572
Reported-by: Pavel Kysilka <goldenfish@linuxsoft.cz>
Reported-by: Matias A. Fonzo <selk@dragora.org>
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: 2.6.28+ <stable@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib/lru_cache.c')
0 files changed, 0 insertions, 0 deletions