Commit 7bbb015f authored Sep 04, 2024 by Liam R. Howlett Committed by Wen Zhiwei Oct 29, 2024

mm/damon/vaddr: protect vma traversal in __damon_va_thre_regions() with rcu read lock

stable inclusion
from stable-v6.6.54
commit b35a42bdaf18bd6f2e3137f7072567040ea5d81e
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/IAZ3K2

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b35a42bdaf18bd6f2e3137f7072567040ea5d81e

--------------------------------

commit fb497d6db7c19c797cbd694b52d1af87c4eebcc6 upstream.

Traversing VMAs of a given maple tree should be protected by rcu read
lock.  However, __damon_va_three_regions() is not doing the protection.
Hold the lock.

Link: https://lkml.kernel.org/r/20240905001204.1481-1-sj@kernel.org


Fixes: d0cf3dd4 ("damon: convert __damon_va_three_regions to use the VMA iterator")
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: SeongJae Park <sj@kernel.org>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Closes: https://lore.kernel.org/b83651a0-5b24-4206-b860-cb54ffdf209b@roeck-us.net


Tested-by: Guenter Roeck <linux@roeck-us.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Wen Zhiwei <wenzhiwei@kylinos.cn>

parent da133ba1

mm/damon/vaddr.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -126,6 +126,7 @@ static int __damon_va_three_regions(struct mm_struct *mm,
		* If this is too slow, it can be optimised to examine the maple
		* tree gaps.
		*/
		rcu_read_lock();
		for_each_vma(vmi, vma) {
		unsigned long gap;

		@@ -146,6 +147,7 @@ static int __damon_va_three_regions(struct mm_struct *mm,
		next:
		prev = vma;
		}
		rcu_read_unlock();

		if (!sz_range(&second_gap) \|\| !sz_range(&first_gap))
		return -EINVAL;