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 6B65E1624E9 for ; Mon, 20 Oct 2025 12:56:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760964966; cv=none; b=MO2AzWDcYoOH02hUjCYKJA/9aejmng7tyePDBaGROACW5PGPJL3RezUQwi7TM9bCyl4MjAavlV/IE3J3gPKqqQSYNaAX7dghrfu4/t6PXXyZLn+9D0RwBNx4pJWMqCUabMMDt8sTKcclVLIIJCbUY8xBahg1WiFvetWSiLUgz3E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760964966; c=relaxed/simple; bh=0e/hiJDL+SsTyJUNYdry2hi4lOu2u+4dw7H35Gyvjck=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=e69BUs0s7N268AF9PH4EggBVxsnQnTGJ0EAoGkGZRYymHyVvfu09Xvxht+owMWIMULeGbTQ/qTM4bG7to7uQ0/UJT10PG5/3z6EGkZZIJ/CQir4PG+xodKSTe4NDtgk4xS7NANNCZ45kBqAqrLg0YXIixNx5xA9OroDuj14V6XU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Cvlp6gte; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Cvlp6gte" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6BC9AC4CEF9; Mon, 20 Oct 2025 12:56:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1760964966; bh=0e/hiJDL+SsTyJUNYdry2hi4lOu2u+4dw7H35Gyvjck=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Cvlp6gtetQ04mfQt/FXCkAgBLmDGgNtK7FMnENHf8HGKyZqRU78CZVoLQYiJdimGA 1z7HeDVzyrYRCrNQhb0VzzDJCuSnTNWWK3B0ZIPQhCsA2pSJyzzL8OBSf3DVhEuDzU HhmRjEwHEgsLDUkLr0xUNmqaFSyOykz1AWo6id7ZDpsStTr8UpNU8WOWV8hjTdrC2w VSgErBfz26JVWiy9zWKyE0GLl7YYQmHECL6WqK5382KuwB7k9NcFiPMMJpJSLiYPi0 wdjV0S46wxirtdWKQkrWcGlRxlnFOstyEsWQCzWgfaVheJWwvaQ8EbuJqzxbOD+d1z 5ExowLHk4U6Fw== From: Sasha Levin To: stable@vger.kernel.org Cc: Sergey Bashirov , Chuck Lever , Sasha Levin Subject: [PATCH 5.15.y 1/3] NFSD: Rework encoding and decoding of nfsd4_deviceid Date: Mon, 20 Oct 2025 08:56:00 -0400 Message-ID: <20251020125602.1761375-1-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <2025101659-tightly-grandma-7323@gregkh> References: <2025101659-tightly-grandma-7323@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Sergey Bashirov [ Upstream commit 832738e4b325b742940761e10487403f9aad13e8 ] Compilers may optimize the layout of C structures, so we should not rely on sizeof struct and memcpy to encode and decode XDR structures. The byte order of the fields should also be taken into account. This patch adds the correct functions to handle the deviceid4 structure and removes the pad field, which is currently not used by NFSD, from the runtime state. The server's byte order is preserved because the deviceid4 blob on the wire is only used as a cookie by the client. Signed-off-by: Sergey Bashirov Signed-off-by: Chuck Lever Stable-dep-of: d68886bae76a ("NFSD: Fix last write offset handling in layoutcommit") Signed-off-by: Sasha Levin --- fs/nfsd/blocklayoutxdr.c | 7 ++----- fs/nfsd/flexfilelayoutxdr.c | 3 +-- fs/nfsd/nfs4layouts.c | 1 - fs/nfsd/nfs4xdr.c | 14 +------------- fs/nfsd/xdr4.h | 36 +++++++++++++++++++++++++++++++++++- 5 files changed, 39 insertions(+), 22 deletions(-) diff --git a/fs/nfsd/blocklayoutxdr.c b/fs/nfsd/blocklayoutxdr.c index 1ed2f691ebb90..dd35c472eb37d 100644 --- a/fs/nfsd/blocklayoutxdr.c +++ b/fs/nfsd/blocklayoutxdr.c @@ -29,8 +29,7 @@ nfsd4_block_encode_layoutget(struct xdr_stream *xdr, *p++ = cpu_to_be32(len); *p++ = cpu_to_be32(1); /* we always return a single extent */ - p = xdr_encode_opaque_fixed(p, &b->vol_id, - sizeof(struct nfsd4_deviceid)); + p = svcxdr_encode_deviceid4(p, &b->vol_id); p = xdr_encode_hyper(p, b->foff); p = xdr_encode_hyper(p, b->len); p = xdr_encode_hyper(p, b->soff); @@ -145,9 +144,7 @@ nfsd4_block_decode_layoutupdate(__be32 *p, u32 len, struct iomap **iomapp, for (i = 0; i < nr_iomaps; i++) { struct pnfs_block_extent bex; - memcpy(&bex.vol_id, p, sizeof(struct nfsd4_deviceid)); - p += XDR_QUADLEN(sizeof(struct nfsd4_deviceid)); - + p = svcxdr_decode_deviceid4(p, &bex.vol_id); p = xdr_decode_hyper(p, &bex.foff); if (bex.foff & (block_size - 1)) { dprintk("%s: unaligned offset 0x%llx\n", diff --git a/fs/nfsd/flexfilelayoutxdr.c b/fs/nfsd/flexfilelayoutxdr.c index bb205328e043d..223a10f37898e 100644 --- a/fs/nfsd/flexfilelayoutxdr.c +++ b/fs/nfsd/flexfilelayoutxdr.c @@ -54,8 +54,7 @@ nfsd4_ff_encode_layoutget(struct xdr_stream *xdr, *p++ = cpu_to_be32(1); /* single mirror */ *p++ = cpu_to_be32(1); /* single data server */ - p = xdr_encode_opaque_fixed(p, &fl->deviceid, - sizeof(struct nfsd4_deviceid)); + p = svcxdr_encode_deviceid4(p, &fl->deviceid); *p++ = cpu_to_be32(1); /* efficiency */ diff --git a/fs/nfsd/nfs4layouts.c b/fs/nfsd/nfs4layouts.c index e4e23b2a3e655..d0fbbd34db689 100644 --- a/fs/nfsd/nfs4layouts.c +++ b/fs/nfsd/nfs4layouts.c @@ -120,7 +120,6 @@ nfsd4_set_deviceid(struct nfsd4_deviceid *id, const struct svc_fh *fhp, id->fsid_idx = fhp->fh_export->ex_devid_map->idx; id->generation = device_generation; - id->pad = 0; return 0; } diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 0fb48e0c179da..3a9f929cdb31e 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -566,18 +566,6 @@ nfsd4_decode_state_owner4(struct nfsd4_compoundargs *argp, } #ifdef CONFIG_NFSD_PNFS -static __be32 -nfsd4_decode_deviceid4(struct nfsd4_compoundargs *argp, - struct nfsd4_deviceid *devid) -{ - __be32 *p; - - p = xdr_inline_decode(argp->xdr, NFS4_DEVICEID4_SIZE); - if (!p) - return nfserr_bad_xdr; - memcpy(devid, p, sizeof(*devid)); - return nfs_ok; -} static __be32 nfsd4_decode_layoutupdate4(struct nfsd4_compoundargs *argp, @@ -1733,7 +1721,7 @@ nfsd4_decode_getdeviceinfo(struct nfsd4_compoundargs *argp, __be32 status; memset(gdev, 0, sizeof(*gdev)); - status = nfsd4_decode_deviceid4(argp, &gdev->gd_devid); + status = nfsd4_decode_deviceid4(argp->xdr, &gdev->gd_devid); if (status) return status; if (xdr_stream_decode_u32(argp->xdr, &gdev->gd_layout_type) < 0) diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h index 9bd1ade6ba54f..c2765619edd4e 100644 --- a/fs/nfsd/xdr4.h +++ b/fs/nfsd/xdr4.h @@ -459,9 +459,43 @@ struct nfsd4_reclaim_complete { struct nfsd4_deviceid { u64 fsid_idx; u32 generation; - u32 pad; }; +static inline __be32 * +svcxdr_encode_deviceid4(__be32 *p, const struct nfsd4_deviceid *devid) +{ + __be64 *q = (__be64 *)p; + + *q = (__force __be64)devid->fsid_idx; + p += 2; + *p++ = (__force __be32)devid->generation; + *p++ = xdr_zero; + return p; +} + +static inline __be32 * +svcxdr_decode_deviceid4(__be32 *p, struct nfsd4_deviceid *devid) +{ + __be64 *q = (__be64 *)p; + + devid->fsid_idx = (__force u64)(*q); + p += 2; + devid->generation = (__force u32)(*p++); + p++; /* NFSD does not use the remaining octets */ + return p; +} + +static inline __be32 +nfsd4_decode_deviceid4(struct xdr_stream *xdr, struct nfsd4_deviceid *devid) +{ + __be32 *p = xdr_inline_decode(xdr, NFS4_DEVICEID4_SIZE); + + if (unlikely(!p)) + return nfserr_bad_xdr; + svcxdr_decode_deviceid4(p, devid); + return nfs_ok; +} + struct nfsd4_layout_seg { u32 iomode; u64 offset; -- 2.51.0