From: Yu Kuai yukuai3@huawei.com
mainline inclusion from mainline-v6.7-rc1 commit 617787f1386da5e851dad68926a31522134d352b category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8T02O
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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Protect 'suspend_lo' and 'suspend_hi' with READ_ONCE/WRITE_ONCE to prevent reading abnormal values.
Signed-off-by: Yu Kuai yukuai3@huawei.com Signed-off-by: Song Liu song@kernel.org Link: https://lore.kernel.org/r/20231010151958.145896-2-yukuai1@huaweicloud.com Signed-off-by: Li Nan linan122@huawei.com --- drivers/md/md.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-)
diff --git a/drivers/md/md.c b/drivers/md/md.c index 3695653cf365..331e0c1f6938 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -359,11 +359,11 @@ static bool is_suspended(struct mddev *mddev, struct bio *bio) return true; if (bio_data_dir(bio) != WRITE) return false; - if (mddev->suspend_lo >= mddev->suspend_hi) + if (READ_ONCE(mddev->suspend_lo) >= READ_ONCE(mddev->suspend_hi)) return false; - if (bio->bi_iter.bi_sector >= mddev->suspend_hi) + if (bio->bi_iter.bi_sector >= READ_ONCE(mddev->suspend_hi)) return false; - if (bio_end_sector(bio) < mddev->suspend_lo) + if (bio_end_sector(bio) < READ_ONCE(mddev->suspend_lo)) return false; return true; } @@ -5172,7 +5172,8 @@ __ATTR(sync_max, S_IRUGO|S_IWUSR, max_sync_show, max_sync_store); static ssize_t suspend_lo_show(struct mddev *mddev, char *page) { - return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_lo); + return sprintf(page, "%llu\n", + (unsigned long long)READ_ONCE(mddev->suspend_lo)); }
static ssize_t @@ -5192,7 +5193,7 @@ suspend_lo_store(struct mddev *mddev, const char *buf, size_t len) return err;
mddev_suspend(mddev); - mddev->suspend_lo = new; + WRITE_ONCE(mddev->suspend_lo, new); mddev_resume(mddev);
mddev_unlock(mddev); @@ -5204,7 +5205,8 @@ __ATTR(suspend_lo, S_IRUGO|S_IWUSR, suspend_lo_show, suspend_lo_store); static ssize_t suspend_hi_show(struct mddev *mddev, char *page) { - return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_hi); + return sprintf(page, "%llu\n", + (unsigned long long)READ_ONCE(mddev->suspend_hi)); }
static ssize_t @@ -5224,7 +5226,7 @@ suspend_hi_store(struct mddev *mddev, const char *buf, size_t len) return err;
mddev_suspend(mddev); - mddev->suspend_hi = new; + WRITE_ONCE(mddev->suspend_hi, new); mddev_resume(mddev);
mddev_unlock(mddev);