From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 86DE03644A0 for ; Sat, 5 Sep 2026 20:05:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788638721; cv=none; b=HRAPAOJns7WHBcjdutUGl5BK3AL8FethHkjw7k8qP9KlMSbm5H6bjHRhkClwhZPpA/L0dCoebmQJa1ozobL1z+Duq/WKPAgsIhCFJWnCxt3PsgO8VIBXY4hPchA75amIDml793q8ZkqsVV80CZtV1d4EFds4jce2bGJj3BObOWE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788638721; c=relaxed/simple; bh=2uvuErZQ2meuRx1dJ7atnDAEUrZhCHS+O0WWDfpECOs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=OzKkHUq59/7AFiD8A8ZLgJgAVXxkiPjfgLRcl3LKa3dqv2hqVn3lDD7O8mcIgRLYw3Ztjj2XZOjpEHCAcdXo9LWdwnqJ9oXNwy2uSm//2irtCH0RQrkGrh3pQfoGoRYaKHIih6gg+6fCVbe6h1GBD6g8F5pJyzTwG4PsyXLjJYk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bYJszQe7; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="bYJszQe7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C1B061F00A3E; Sat, 5 Sep 2026 20:05:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788638720; bh=/aF9lDhDb3DFJ73Wlata1W2FzBb6J+GTo0d/benturE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=bYJszQe7z+g+sSdCg4wzPjPYj/XS4mvFa8e7+LwEi36FcnrTk9umWH6r89OkberTN 5etJMeh6Q7JexszQnRl/5q/fznakToqVV1uHIyIuVU14IeYmR2B01bKm9jsS3sm4CP T72fTox/IXNV30d4sLs9j37xUbsyy1x+4CC9ZhALRY/1apwW16wQUL9vaXorRq/FZH VBzfD3SsZwdmDjBWtBJCR9O9WBdyonj4jgJ6v9SBAfhWbsSU16bOLUXCStTokiMAoi Nbh6+eykgJ0yvOJ3TTMFIScZX11yGCUQjQOFtlpdxhegbFxMG7he3QO6Cj4iQL5wYG yuw3MSp7pr4HA== From: Sasha Levin To: stable@vger.kernel.org Cc: Jeff Layton , Chuck Lever , Sasha Levin Subject: [PATCH 6.12.y 2/2] nfsd: fix stale s2s_cp_stateids IDR entry for async COPY Date: Sat, 5 Sep 2026 16:05:17 -0400 Message-ID: <20260905200517.607056-2-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260905200517.607056-1-sashal@kernel.org> References: <2026090320-purple-stiffness-b344@gregkh> <20260905200517.607056-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Jeff Layton [ Upstream commit d0beaee498e11880e72826026db0e9c9890fc114 ] For an async COPY, nfsd4_copy() called nfs4_init_copy_state() before dup_copy_fields(), so the s2s_cp_stateids IDR was pointed at &u->copy->cp_stateid -- memory in the per-rqstp COMPOUND buffer that is reused by the next request. dup_copy_fields() copies only the value into async_copy, so the IDR slot dangled at the transient buffer for the whole background copy. Any IDR walker then dereferences reused request memory: the laundromat reads cs_type from it and, if the bytes look like an expired NFS4_COPYNOTIFY_STID, follows into refcount_dec()/idr_remove()/kfree() on garbage; manage_cpntf_state() has the same exposure via idr_find(). Duplicate the fields first, then register the stateid on the stable async_copy. result->cb_stateid is unchanged. Fixes: e0639dc5805a ("NFSD introduce async copy feature") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20260710-nfsd-testing-v3-3-a0ff7db6aa3e@kernel.org Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin --- fs/nfsd/nfs4proc.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index ee67978996293..d4b47f43b07d8 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -1854,11 +1854,12 @@ nfsd4_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, async_copy->cp_src = kmalloc(sizeof(*async_copy->cp_src), GFP_KERNEL); if (!async_copy->cp_src) goto out_dec_async_copy_err; - if (!nfs4_init_copy_state(nn, copy)) + dup_copy_fields(copy, async_copy); + + if (!nfs4_init_copy_state(nn, async_copy)) goto out_dec_async_copy_err; - memcpy(&result->cb_stateid, ©->cp_stateid.cs_stid, + memcpy(&result->cb_stateid, &async_copy->cp_stateid.cs_stid, sizeof(result->cb_stateid)); - dup_copy_fields(copy, async_copy); if ((READ_ONCE(copy->nf_dst->nf_file->f_mode) & FMODE_NOCMTIME) != 0) async_copy->attr_update = true; -- 2.53.0