From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E6D411ED38 for ; Tue, 25 Jul 2023 11:11:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6714BC433C8; Tue, 25 Jul 2023 11:11:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1690283494; bh=KeRhk83MhruqRoA9820t8Qu5f0ERdwl5+FHCOt7QBJ0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ykCoVuDX/QKMTFSmhjvwkmbE+fGh3MDPQwEga5wxCKjevFfEP5b9BWBKiLuXdYggF aONxsPHyDVPm0j+1UAKEnrBUOEZan8MvJYWsIMypNrn0CMbnZNA/AzbtTmMcXy9yZk 8dAy9d7qpXkxD27lkQF2YUuuS4+kosxjhEBiSzgE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Li Nan , Yu Kuai , Song Liu , Sasha Levin Subject: [PATCH 5.10 018/509] md/raid10: fix null-ptr-deref of mreplace in raid10_sync_request Date: Tue, 25 Jul 2023 12:39:17 +0200 Message-ID: <20230725104554.485706292@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230725104553.588743331@linuxfoundation.org> References: <20230725104553.588743331@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Li Nan [ Upstream commit 34817a2441747b48e444cb0e05d84e14bc9443da ] There are two check of 'mreplace' in raid10_sync_request(). In the first check, 'need_replace' will be set and 'mreplace' will be used later if no-Faulty 'mreplace' exists, In the second check, 'mreplace' will be set to NULL if it is Faulty, but 'need_replace' will not be changed accordingly. null-ptr-deref occurs if Faulty is set between two check. Fix it by merging two checks into one. And replace 'need_replace' with 'mreplace' because their values are always the same. Fixes: ee37d7314a32 ("md/raid10: Fix raid10 replace hang when new added disk faulty") Signed-off-by: Li Nan Reviewed-by: Yu Kuai Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20230527072218.2365857-2-linan666@huaweicloud.com Signed-off-by: Sasha Levin --- drivers/md/raid10.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 6a0459f9fafbc..01680029f0de5 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -3037,7 +3037,6 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr, int must_sync; int any_working; int need_recover = 0; - int need_replace = 0; struct raid10_info *mirror = &conf->mirrors[i]; struct md_rdev *mrdev, *mreplace; @@ -3049,11 +3048,10 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr, !test_bit(Faulty, &mrdev->flags) && !test_bit(In_sync, &mrdev->flags)) need_recover = 1; - if (mreplace != NULL && - !test_bit(Faulty, &mreplace->flags)) - need_replace = 1; + if (mreplace && test_bit(Faulty, &mreplace->flags)) + mreplace = NULL; - if (!need_recover && !need_replace) { + if (!need_recover && !mreplace) { rcu_read_unlock(); continue; } @@ -3069,8 +3067,6 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr, rcu_read_unlock(); continue; } - if (mreplace && test_bit(Faulty, &mreplace->flags)) - mreplace = NULL; /* Unless we are doing a full sync, or a replacement * we only need to recover the block if it is set in * the bitmap @@ -3193,11 +3189,11 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr, bio = r10_bio->devs[1].repl_bio; if (bio) bio->bi_end_io = NULL; - /* Note: if need_replace, then bio + /* Note: if replace is not NULL, then bio * cannot be NULL as r10buf_pool_alloc will * have allocated it. */ - if (!need_replace) + if (!mreplace) break; bio->bi_next = biolist; biolist = bio; -- 2.39.2