From 762d2b24a7628c8070427804fe5601891164cd22 Mon Sep 17 00:00:00 2001 From: Wang Jinchao Date: Tue, 5 Aug 2025 22:01:36 +0800 Subject: [PATCH] md/raid1: Fix stack memory use after return in raid1_reshape stable inclusion from stable-v6.6.99 commit df5894014a92ff0196dbc212a7764e97366fd2b7 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/ICOXOC CVE: CVE-2025-38445 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=df5894014a92ff0196dbc212a7764e97366fd2b7 ------------------ [ Upstream commit d67ed2ccd2d1dcfda9292c0ea8697a9d0f2f0d98 ] In the raid1_reshape function, newpool is allocated on the stack and assigned to conf->r1bio_pool. This results in conf->r1bio_pool.wait.head pointing to a stack address. Accessing this address later can lead to a kernel panic. Example access path: raid1_reshape() { // newpool is on the stack mempool_t newpool, oldpool; // initialize newpool.wait.head to stack address mempool_init(&newpool, ...); conf->r1bio_pool = newpool; } raid1_read_request() or raid1_write_request() { alloc_r1bio() { mempool_alloc() { // if pool->alloc fails remove_element() { --pool->curr_nr; } } } } mempool_free() { if (pool->curr_nr < pool->min_nr) { // pool->wait.head is a stack address // wake_up() will try to access this invalid address // which leads to a kernel panic return; wake_up(&pool->wait); } } Fix: reinit conf->r1bio_pool.wait after assigning newpool. Fixes: afeee514ce7f ("md: convert to bioset_init()/mempool_init()") Signed-off-by: Wang Jinchao Reviewed-by: Yu Kuai Link: https://lore.kernel.org/linux-raid/20250612112901.3023950-1-wangjinchao600@gmail.com Signed-off-by: Yu Kuai Signed-off-by: Sasha Levin Signed-off-by: Zheng Qixing --- drivers/md/raid1.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 4b7e68276d6c..8741b10db2bc 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -3263,6 +3263,7 @@ static int raid1_reshape(struct mddev *mddev) /* ok, everything is stopped */ oldpool = conf->r1bio_pool; conf->r1bio_pool = newpool; + init_waitqueue_head(&conf->r1bio_pool.wait); for (d = d2 = 0; d < conf->raid_disks; d++) { struct md_rdev *rdev = conf->mirrors[d].rdev; -- Gitee