https://github.com/torvalds/linux
Revision f683739539e819e9b821a197d80e52258510837b authored by Naoya Horiguchi on 25 March 2015, 22:55:14 UTC, committed by Linus Torvalds on 25 March 2015, 23:20:30 UTC
walk_page_test() is purely pagewalk's internal stuff, and its positive
return values are not intended to be passed to the callers of pagewalk.

However, in the current code if the last vma in the do-while loop in
walk_page_range() happens to return a positive value, it leaks outside
walk_page_range().  So the user visible effect is invalid/unexpected
return value (according to the reporter, mbind() causes it.)

This patch fixes it simply by reinitializing the return value after
checked.

Another exposed interface, walk_page_vma(), already returns 0 for such
cases so no problem.

Fixes: fafaa4264eba ("pagewalk: improve vma handling")
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Kazutomo Yoshii <kazutomo.yoshii@gmail.com>
Reported-by: Kazutomo Yoshii <kazutomo.yoshii@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 3fe89b3
History
Tip revision: f683739539e819e9b821a197d80e52258510837b authored by Naoya Horiguchi on 25 March 2015, 22:55:14 UTC
mm/pagewalk.c: prevent positive return value of walk_page_test() from being passed to callers
Tip revision: f683739
File Mode Size
Documentation
arch
block
crypto
drivers
firmware
fs
include
init
ipc
kernel
lib
mm
net
samples
scripts
security
sound
tools
usr
virt
.gitignore -rw-r--r-- 1.2 KB
.mailmap -rw-r--r-- 4.9 KB
COPYING -rw-r--r-- 18.3 KB
CREDITS -rw-r--r-- 94.0 KB
Kbuild -rw-r--r-- 2.1 KB
Kconfig -rw-r--r-- 252 bytes
MAINTAINERS -rw-r--r-- 298.8 KB
Makefile -rw-r--r-- 53.3 KB
README -rw-r--r-- 18.3 KB
REPORTING-BUGS -rw-r--r-- 7.3 KB

README

back to top