This is a note to let you know that I've just added the patch titled
SUNRPC: Add xdr_set_scratch_page() and xdr_reset_scratch_buffer()
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
sunrpc-add-xdr_set_scratch_page-and-xdr_reset_scratc.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 520c12fe7527e8c6fa85982c46d0d079fa704a08
Author: Chuck Lever <chuck.lever@xxxxxxxxxx>
Date: Wed Nov 11 15:52:47 2020 -0500
SUNRPC: Add xdr_set_scratch_page() and xdr_reset_scratch_buffer()
[ Upstream commit 0ae4c3e8a64ace1b8d7de033b0751afe43024416 ]
Clean up: De-duplicate some frequently-used code.
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
Stable-dep-of: 401bc1f90874 ("NFSD: Protect against send buffer overflow in NFSv2 READ")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/nfs/blocklayout/blocklayout.c b/fs/nfs/blocklayout/blocklayout.c
index 08108b6d2fa1..3be6836074ae 100644
--- a/fs/nfs/blocklayout/blocklayout.c
+++ b/fs/nfs/blocklayout/blocklayout.c
@@ -697,7 +697,7 @@ bl_alloc_lseg(struct pnfs_layout_hdr *lo, struct nfs4_layoutget_res *lgr,
xdr_init_decode_pages(&xdr, &buf,
lgr->layoutp->pages, lgr->layoutp->len);
- xdr_set_scratch_buffer(&xdr, page_address(scratch), PAGE_SIZE);
+ xdr_set_scratch_page(&xdr, scratch);
status = -EIO;
p = xdr_inline_decode(&xdr, 4);
diff --git a/fs/nfs/blocklayout/dev.c b/fs/nfs/blocklayout/dev.c
index dec5880ac6de..acb1d22907da 100644
--- a/fs/nfs/blocklayout/dev.c
+++ b/fs/nfs/blocklayout/dev.c
@@ -510,7 +510,7 @@ bl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
goto out;
xdr_init_decode_pages(&xdr, &buf, pdev->pages, pdev->pglen);
- xdr_set_scratch_buffer(&xdr, page_address(scratch), PAGE_SIZE);
+ xdr_set_scratch_page(&xdr, scratch);
p = xdr_inline_decode(&xdr, sizeof(__be32));
if (!p)
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 9f88ca7b2001..935029632d5f 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -576,7 +576,7 @@ int nfs_readdir_page_filler(nfs_readdir_descriptor_t *desc, struct nfs_entry *en
goto out_nopages;
xdr_init_decode_pages(&stream, &buf, xdr_pages, buflen);
- xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
+ xdr_set_scratch_page(&stream, scratch);
do {
if (entry->label)
diff --git a/fs/nfs/filelayout/filelayout.c b/fs/nfs/filelayout/filelayout.c
index ae5ed3a07494..d2103852475f 100644
--- a/fs/nfs/filelayout/filelayout.c
+++ b/fs/nfs/filelayout/filelayout.c
@@ -666,7 +666,7 @@ filelayout_decode_layout(struct pnfs_layout_hdr *flo,
return -ENOMEM;
xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages, lgr->layoutp->len);
- xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
+ xdr_set_scratch_page(&stream, scratch);
/* 20 = ufl_util (4), first_stripe_index (4), pattern_offset (8),
* num_fh (4) */
diff --git a/fs/nfs/filelayout/filelayoutdev.c b/fs/nfs/filelayout/filelayoutdev.c
index d913e818858f..86c3f7e69ec4 100644
--- a/fs/nfs/filelayout/filelayoutdev.c
+++ b/fs/nfs/filelayout/filelayoutdev.c
@@ -82,7 +82,7 @@ nfs4_fl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
goto out_err;
xdr_init_decode_pages(&stream, &buf, pdev->pages, pdev->pglen);
- xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
+ xdr_set_scratch_page(&stream, scratch);
/* Get the stripe count (number of stripe index) */
p = xdr_inline_decode(&stream, 4);
diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index a8a02081942d..0200d96b8d5b 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -378,7 +378,7 @@ ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages,
lgr->layoutp->len);
- xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
+ xdr_set_scratch_page(&stream, scratch);
/* stripe unit and mirror_array_cnt */
rc = -EIO;
diff --git a/fs/nfs/flexfilelayout/flexfilelayoutdev.c b/fs/nfs/flexfilelayout/flexfilelayoutdev.c
index 1f12297109b4..bfa7202ca7be 100644
--- a/fs/nfs/flexfilelayout/flexfilelayoutdev.c
+++ b/fs/nfs/flexfilelayout/flexfilelayoutdev.c
@@ -69,7 +69,7 @@ nfs4_ff_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
INIT_LIST_HEAD(&dsaddrs);
xdr_init_decode_pages(&stream, &buf, pdev->pages, pdev->pglen);
- xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
+ xdr_set_scratch_page(&stream, scratch);
/* multipath count */
p = xdr_inline_decode(&stream, 4);
diff --git a/fs/nfs/nfs42xdr.c b/fs/nfs/nfs42xdr.c
index f2248d9d4db5..df5bee2f505c 100644
--- a/fs/nfs/nfs42xdr.c
+++ b/fs/nfs/nfs42xdr.c
@@ -1536,7 +1536,7 @@ static int nfs4_xdr_dec_listxattrs(struct rpc_rqst *rqstp,
struct compound_hdr hdr;
int status;
- xdr_set_scratch_buffer(xdr, page_address(res->scratch), PAGE_SIZE);
+ xdr_set_scratch_page(xdr, res->scratch);
status = decode_compound_hdr(xdr, &hdr);
if (status)
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index e2f0e3446e22..f21dc4284468 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -6406,10 +6406,8 @@ nfs4_xdr_dec_getacl(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
struct compound_hdr hdr;
int status;
- if (res->acl_scratch != NULL) {
- void *p = page_address(res->acl_scratch);
- xdr_set_scratch_buffer(xdr, p, PAGE_SIZE);
- }
+ if (res->acl_scratch != NULL)
+ xdr_set_scratch_page(xdr, res->acl_scratch);
status = decode_compound_hdr(xdr, &hdr);
if (status)
goto out;
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 735ee8a79870..9aeeb51e8c61 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -2274,7 +2274,7 @@ static void svcxdr_init_encode(struct svc_rqst *rqstp,
xdr->end = head->iov_base + PAGE_SIZE - rqstp->rq_auth_slack;
/* Tail and page_len should be zero at this point: */
buf->len = buf->head[0].iov_len;
- xdr->scratch.iov_len = 0;
+ xdr_reset_scratch_buffer(xdr);
xdr->page_ptr = buf->pages - 1;
buf->buflen = PAGE_SIZE * (1 + rqstp->rq_page_end - buf->pages)
- rqstp->rq_auth_slack;
diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h
index 6d9d1520612b..0c8cab6210b3 100644
--- a/include/linux/sunrpc/xdr.h
+++ b/include/linux/sunrpc/xdr.h
@@ -246,7 +246,6 @@ extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf,
__be32 *p, struct rpc_rqst *rqst);
extern void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf,
struct page **pages, unsigned int len);
-extern void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen);
extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
@@ -254,6 +253,49 @@ extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned in
extern uint64_t xdr_align_data(struct xdr_stream *, uint64_t, uint32_t);
extern uint64_t xdr_expand_hole(struct xdr_stream *, uint64_t, uint64_t);
+/**
+ * xdr_set_scratch_buffer - Attach a scratch buffer for decoding data.
+ * @xdr: pointer to xdr_stream struct
+ * @buf: pointer to an empty buffer
+ * @buflen: size of 'buf'
+ *
+ * The scratch buffer is used when decoding from an array of pages.
+ * If an xdr_inline_decode() call spans across page boundaries, then
+ * we copy the data into the scratch buffer in order to allow linear
+ * access.
+ */
+static inline void
+xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen)
+{
+ xdr->scratch.iov_base = buf;
+ xdr->scratch.iov_len = buflen;
+}
+
+/**
+ * xdr_set_scratch_page - Attach a scratch buffer for decoding data
+ * @xdr: pointer to xdr_stream struct
+ * @page: an anonymous page
+ *
+ * See xdr_set_scratch_buffer().
+ */
+static inline void
+xdr_set_scratch_page(struct xdr_stream *xdr, struct page *page)
+{
+ xdr_set_scratch_buffer(xdr, page_address(page), PAGE_SIZE);
+}
+
+/**
+ * xdr_reset_scratch_buffer - Clear scratch buffer information
+ * @xdr: pointer to xdr_stream struct
+ *
+ * See xdr_set_scratch_buffer().
+ */
+static inline void
+xdr_reset_scratch_buffer(struct xdr_stream *xdr)
+{
+ xdr_set_scratch_buffer(xdr, NULL, 0);
+}
+
/**
* xdr_stream_remaining - Return the number of bytes remaining in the stream
* @xdr: pointer to struct xdr_stream
diff --git a/net/sunrpc/auth_gss/gss_rpc_xdr.c b/net/sunrpc/auth_gss/gss_rpc_xdr.c
index 2ff7b7083eba..c636c648849b 100644
--- a/net/sunrpc/auth_gss/gss_rpc_xdr.c
+++ b/net/sunrpc/auth_gss/gss_rpc_xdr.c
@@ -789,7 +789,7 @@ int gssx_dec_accept_sec_context(struct rpc_rqst *rqstp,
scratch = alloc_page(GFP_KERNEL);
if (!scratch)
return -ENOMEM;
- xdr_set_scratch_buffer(xdr, page_address(scratch), PAGE_SIZE);
+ xdr_set_scratch_page(xdr, scratch);
/* res->status */
err = gssx_dec_status(xdr, &res->status);
diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index d84bb5037bb5..02adc5c7f034 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -669,7 +669,7 @@ void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p,
struct kvec *iov = buf->head;
int scratch_len = buf->buflen - buf->page_len - buf->tail[0].iov_len;
- xdr_set_scratch_buffer(xdr, NULL, 0);
+ xdr_reset_scratch_buffer(xdr);
BUG_ON(scratch_len < 0);
xdr->buf = buf;
xdr->iov = iov;
@@ -713,7 +713,7 @@ inline void xdr_commit_encode(struct xdr_stream *xdr)
page = page_address(*xdr->page_ptr);
memcpy(xdr->scratch.iov_base, page, shift);
memmove(page, page + shift, (void *)xdr->p - page);
- xdr->scratch.iov_len = 0;
+ xdr_reset_scratch_buffer(xdr);
}
EXPORT_SYMBOL_GPL(xdr_commit_encode);
@@ -743,8 +743,7 @@ static __be32 *xdr_get_next_encode_buffer(struct xdr_stream *xdr,
* the "scratch" iov to track any temporarily unused fragment of
* space at the end of the previous buffer:
*/
- xdr->scratch.iov_base = xdr->p;
- xdr->scratch.iov_len = frag1bytes;
+ xdr_set_scratch_buffer(xdr, xdr->p, frag1bytes);
p = page_address(*xdr->page_ptr);
/*
* Note this is where the next encode will start after we've
@@ -1056,8 +1055,7 @@ void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p,
struct rpc_rqst *rqst)
{
xdr->buf = buf;
- xdr->scratch.iov_base = NULL;
- xdr->scratch.iov_len = 0;
+ xdr_reset_scratch_buffer(xdr);
xdr->nwords = XDR_QUADLEN(buf->len);
if (buf->head[0].iov_len != 0)
xdr_set_iov(xdr, buf->head, buf->len);
@@ -1105,24 +1103,6 @@ static __be32 * __xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes)
return p;
}
-/**
- * xdr_set_scratch_buffer - Attach a scratch buffer for decoding data.
- * @xdr: pointer to xdr_stream struct
- * @buf: pointer to an empty buffer
- * @buflen: size of 'buf'
- *
- * The scratch buffer is used when decoding from an array of pages.
- * If an xdr_inline_decode() call spans across page boundaries, then
- * we copy the data into the scratch buffer in order to allow linear
- * access.
- */
-void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen)
-{
- xdr->scratch.iov_base = buf;
- xdr->scratch.iov_len = buflen;
-}
-EXPORT_SYMBOL_GPL(xdr_set_scratch_buffer);
-
static __be32 *xdr_copy_to_scratch(struct xdr_stream *xdr, size_t nbytes)
{
__be32 *p;
