From: Alan Cox Date: Wed, 29 Oct 2008 21:01:20 +0000 (-0700) Subject: nfsd: fix vm overcommit crash X-Git-Tag: v2.6.27.47~2 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3f955fe683ffdda7fd68e0b61779001cb9b50011;p=pandora-kernel.git nfsd: fix vm overcommit crash commit 731572d39fcd3498702eda4600db4c43d51e0b26 upstream. Junjiro R. Okajima reported a problem where knfsd crashes if you are using it to export shmemfs objects and run strict overcommit. In this situation the current->mm based modifier to the overcommit goes through a NULL pointer. We could simply check for NULL and skip the modifier but we've caught other real bugs in the past from mm being NULL here - cases where we did need a valid mm set up (eg the exec bug about a year ago). To preserve the checks and get the logic we want shuffle the checking around and add a new helper to the vm_ security wrappers Also fix a current->mm reference in nommu that should use the passed mm [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: fix build] Reported-by: Junjiro R. Okajima Acked-by: James Morris Signed-off-by: Alan Cox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- Reading git-diff-tree failed