2017-02-18 18:18:11

by Trond Myklebust

[permalink] [raw]
Subject: [PATCH v2 0/4] XDR cleanups for NFSv4

Various cleanups and bugfixes for the NFSv4 client XDR code

v2: Add documentation to the generic helpers

Trond Myklebust (4):
SUNRPC: Add generic helpers for xdr_stream encode/decode
NFSv4: Replace ad-hoc xdr encode/decode helpers with xdr_stream_*
generics
NFSv4: Fix the underestimation of delegation XDR space reservation
NFSv4: Remove bogus "struct nfs_client" argument from decode_ace()

fs/nfs/callback_xdr.c | 8 +-
fs/nfs/flexfilelayout/flexfilelayout.c | 5 +-
fs/nfs/nfs4xdr.c | 58 ++++-------
include/linux/sunrpc/xdr.h | 171 +++++++++++++++++++++++++++++++++
4 files changed, 193 insertions(+), 49 deletions(-)

--
2.9.3



2017-02-18 18:18:14

by Trond Myklebust

[permalink] [raw]
Subject: [PATCH v2 2/4] NFSv4: Replace ad-hoc xdr encode/decode helpers with xdr_stream_* generics

Signed-off-by: Trond Myklebust <[email protected]>
---
fs/nfs/callback_xdr.c | 8 ++----
fs/nfs/flexfilelayout/flexfilelayout.c | 5 +---
fs/nfs/nfs4xdr.c | 52 ++++++++++------------------------
3 files changed, 18 insertions(+), 47 deletions(-)

diff --git a/fs/nfs/callback_xdr.c b/fs/nfs/callback_xdr.c
index eb094c6011d8..e732a65db546 100644
--- a/fs/nfs/callback_xdr.c
+++ b/fs/nfs/callback_xdr.c
@@ -582,12 +582,8 @@ static __be32 decode_notify_lock_args(struct svc_rqst *rqstp, struct xdr_stream

static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
{
- __be32 *p;
-
- p = xdr_reserve_space(xdr, 4 + len);
- if (unlikely(p == NULL))
- return htonl(NFS4ERR_RESOURCE);
- xdr_encode_opaque(p, str, len);
+ if (unlikely(xdr_stream_encode_opaque(xdr, str, len) < 0))
+ return cpu_to_be32(NFS4ERR_RESOURCE);
return 0;
}

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index 42e3e9daa328..471efdc2589d 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -1966,10 +1966,7 @@ static int ff_layout_encode_ioerr(struct xdr_stream *xdr,
static void
encode_opaque_fixed(struct xdr_stream *xdr, const void *buf, size_t len)
{
- __be32 *p;
-
- p = xdr_reserve_space(xdr, len);
- xdr_encode_opaque_fixed(p, buf, len);
+ WARN_ON_ONCE(xdr_stream_encode_opaque_fixed(xdr, buf, len) < 0);
}

static void
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index e9255cb453e6..62ff0ff19880 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -924,34 +924,22 @@ static __be32 *reserve_space(struct xdr_stream *xdr, size_t nbytes)

static void encode_opaque_fixed(struct xdr_stream *xdr, const void *buf, size_t len)
{
- __be32 *p;
-
- p = xdr_reserve_space(xdr, len);
- xdr_encode_opaque_fixed(p, buf, len);
+ WARN_ON_ONCE(xdr_stream_encode_opaque_fixed(xdr, buf, len) < 0);
}

static void encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
{
- __be32 *p;
-
- p = reserve_space(xdr, 4 + len);
- xdr_encode_opaque(p, str, len);
+ WARN_ON_ONCE(xdr_stream_encode_opaque(xdr, str, len) < 0);
}

static void encode_uint32(struct xdr_stream *xdr, u32 n)
{
- __be32 *p;
-
- p = reserve_space(xdr, 4);
- *p = cpu_to_be32(n);
+ WARN_ON_ONCE(xdr_stream_encode_u32(xdr, n) < 0);
}

static void encode_uint64(struct xdr_stream *xdr, u64 n)
{
- __be32 *p;
-
- p = reserve_space(xdr, 8);
- xdr_encode_hyper(p, n);
+ WARN_ON_ONCE(xdr_stream_encode_u64(xdr, n) < 0);
}

static void encode_nfs4_seqid(struct xdr_stream *xdr,
@@ -3062,20 +3050,13 @@ static void print_overflow_msg(const char *func, const struct xdr_stream *xdr)

static int decode_opaque_inline(struct xdr_stream *xdr, unsigned int *len, char **string)
{
- __be32 *p;
-
- p = xdr_inline_decode(xdr, 4);
- if (unlikely(!p))
- goto out_overflow;
- *len = be32_to_cpup(p);
- p = xdr_inline_decode(xdr, *len);
- if (unlikely(!p))
- goto out_overflow;
- *string = (char *)p;
+ ssize_t ret = xdr_stream_decode_opaque_inline(xdr, (void **)string);
+ if (unlikely(ret < 0)) {
+ print_overflow_msg(__func__, xdr);
+ return -EIO;
+ }
+ *len = ret;
return 0;
-out_overflow:
- print_overflow_msg(__func__, xdr);
- return -EIO;
}

static int decode_compound_hdr(struct xdr_stream *xdr, struct compound_hdr *hdr)
@@ -4294,15 +4275,12 @@ static int decode_access(struct xdr_stream *xdr, u32 *supported, u32 *access)

static int decode_opaque_fixed(struct xdr_stream *xdr, void *buf, size_t len)
{
- __be32 *p;
-
- p = xdr_inline_decode(xdr, len);
- if (likely(p)) {
- memcpy(buf, p, len);
- return 0;
+ ssize_t ret = xdr_stream_decode_opaque_fixed(xdr, buf, len);
+ if (unlikely(ret < 0)) {
+ print_overflow_msg(__func__, xdr);
+ return -EIO;
}
- print_overflow_msg(__func__, xdr);
- return -EIO;
+ return 0;
}

static int decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
--
2.9.3


2017-02-18 18:18:16

by Trond Myklebust

[permalink] [raw]
Subject: [PATCH v2 4/4] NFSv4: Remove bogus "struct nfs_client" argument from decode_ace()

We shouldn't need to force callers to carry an unused argument.

Signed-off-by: Trond Myklebust <[email protected]>
---
fs/nfs/nfs4xdr.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 7510a0cd93fa..dbb765fb4180 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -3125,7 +3125,7 @@ static int decode_op_hdr(struct xdr_stream *xdr, enum nfs_opnum4 expected)
}

/* Dummy routine */
-static int decode_ace(struct xdr_stream *xdr, void *ace, struct nfs_client *clp)
+static int decode_ace(struct xdr_stream *xdr, void *ace)
{
__be32 *p;
unsigned int strlen;
@@ -5073,7 +5073,7 @@ static int decode_rw_delegation(struct xdr_stream *xdr,
if (decode_space_limit(xdr, &res->pagemod_limit) < 0)
return -EIO;
}
- return decode_ace(xdr, NULL, res->server->nfs_client);
+ return decode_ace(xdr, NULL);
out_overflow:
print_overflow_msg(__func__, xdr);
return -EIO;
--
2.9.3


2017-02-18 18:18:15

by Trond Myklebust

[permalink] [raw]
Subject: [PATCH v2 3/4] NFSv4: Fix the underestimation of delegation XDR space reservation

Account for the "space_limit" field in struct open_write_delegation4.

Fixes: 2cebf82883f4 ("NFSv4: Fix the underestimate of NFSv4 open request size")
Signed-off-by: Trond Myklebust <[email protected]>
---
fs/nfs/nfs4xdr.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 62ff0ff19880..7510a0cd93fa 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -169,8 +169,10 @@ static int nfs4_stat_to_errno(int);
open_owner_id_maxsz + \
encode_opentype_maxsz + \
encode_claim_null_maxsz)
+#define decode_space_limit_maxsz (3)
#define decode_ace_maxsz (3 + nfs4_owner_maxsz)
#define decode_delegation_maxsz (1 + decode_stateid_maxsz + 1 + \
+ decode_space_limit_maxsz + \
decode_ace_maxsz)
#define decode_change_info_maxsz (5)
#define decode_open_maxsz (op_decode_hdr_maxsz + \
--
2.9.3


2017-02-18 18:18:12

by Trond Myklebust

[permalink] [raw]
Subject: [PATCH v2 1/4] SUNRPC: Add generic helpers for xdr_stream encode/decode

Add some generic helpers for encoding/decoding opaque structures and
basic u32/u64.

Signed-off-by: Trond Myklebust <[email protected]>
---
include/linux/sunrpc/xdr.h | 171 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 171 insertions(+)

diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h
index 56c48c884a24..163da0f31d2b 100644
--- a/include/linux/sunrpc/xdr.h
+++ b/include/linux/sunrpc/xdr.h
@@ -242,6 +242,177 @@ 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);
extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);

+/**
+ * xdr_align_size - Calculate padded size of an object
+ * @n: Size of an object being XDR encoded (in bytes)
+ *
+ * Return value:
+ * Size (in bytes) of the object including xdr padding
+ */
+static inline size_t
+xdr_align_size(size_t n)
+{
+ const size_t mask = sizeof(__u32) - 1;
+
+ return (n + mask) & ~mask;
+}
+
+/**
+ * xdr_stream_encode_u32 - Encode a 32-bit integer
+ * @xdr: pointer to xdr_stream
+ * @n: integer to encode
+ *
+ * Return values:
+ * On success, returns length in bytes of XDR buffer consumed
+ * %-ENOBUFS on XDR buffer overflow
+ */
+static inline ssize_t
+xdr_stream_encode_u32(struct xdr_stream *xdr, __u32 n)
+{
+ const size_t len = sizeof(n);
+ __be32 *p = xdr_reserve_space(xdr, len);
+
+ if (unlikely(!p))
+ return -ENOBUFS;
+ *p = cpu_to_be32(n);
+ return len;
+}
+
+/**
+ * xdr_stream_encode_u64 - Encode a 64-bit integer
+ * @xdr: pointer to xdr_stream
+ * @n: 64-bit integer to encode
+ *
+ * Return values:
+ * On success, returns length in bytes of XDR buffer consumed
+ * %-ENOBUFS on XDR buffer overflow
+ */
+static inline ssize_t
+xdr_stream_encode_u64(struct xdr_stream *xdr, __u64 n)
+{
+ const size_t len = sizeof(n);
+ __be32 *p = xdr_reserve_space(xdr, len);
+
+ if (unlikely(!p))
+ return -ENOBUFS;
+ xdr_encode_hyper(p, n);
+ return len;
+}
+
+/**
+ * xdr_stream_encode_opaque_fixed - Encode fixed length opaque xdr data
+ * @xdr: pointer to xdr_stream
+ * @ptr: pointer to opaque data object
+ * @len: size of object pointed to by @ptr
+ *
+ * Return values:
+ * On success, returns length in bytes of XDR buffer consumed
+ * %-ENOBUFS on XDR buffer overflow
+ */
+static inline ssize_t
+xdr_stream_encode_opaque_fixed(struct xdr_stream *xdr, const void *ptr, size_t len)
+{
+ __be32 *p = xdr_reserve_space(xdr, len);
+
+ if (unlikely(!p))
+ return -ENOBUFS;
+ xdr_encode_opaque_fixed(p, ptr, len);
+ return xdr_align_size(len);
+}
+
+/**
+ * xdr_stream_encode_opaque - Encode variable length opaque xdr data
+ * @xdr: pointer to xdr_stream
+ * @ptr: pointer to opaque data object
+ * @len: size of object pointed to by @ptr
+ *
+ * Return values:
+ * On success, returns length in bytes of XDR buffer consumed
+ * %-ENOBUFS on XDR buffer overflow
+ */
+static inline ssize_t
+xdr_stream_encode_opaque(struct xdr_stream *xdr, const void *ptr, size_t len)
+{
+ __be32 *p = xdr_reserve_space(xdr, len);
+
+ if (unlikely(!p))
+ return -ENOBUFS;
+ xdr_encode_opaque(p, ptr, len);
+ return xdr_align_size(len);
+}
+
+/**
+ * xdr_stream_decode_u32 - Decode a 32-bit integer
+ * @xdr: pointer to xdr_stream
+ * @ptr: location to store integer
+ *
+ * Return values:
+ * On success, returns a positive value
+ * %-ENOBUFS on XDR buffer overflow
+ */
+static inline ssize_t
+xdr_stream_decode_u32(struct xdr_stream *xdr, __u32 *ptr)
+{
+ const size_t len = sizeof(*ptr);
+ __be32 *p = xdr_inline_decode(xdr, len);
+ if (unlikely(!p))
+ return -ENOBUFS;
+ *ptr = be32_to_cpup(p);
+ return len;
+}
+
+/**
+ * xdr_stream_decode_opaque_fixed - Decode fixed length opaque xdr data
+ * @xdr: pointer to xdr_stream
+ * @ptr: location to store data
+ * @len: size of buffer pointed to by @ptr
+ *
+ * Return values:
+ * On success, returns size of object stored in @ptr
+ * %-ENOBUFS on XDR buffer overflow
+ */
+static inline ssize_t
+xdr_stream_decode_opaque_fixed(struct xdr_stream *xdr, void *ptr, size_t len)
+{
+ __be32 *p = xdr_inline_decode(xdr, len);
+
+ if (unlikely(!p))
+ return -ENOBUFS;
+ xdr_decode_opaque_fixed(p, ptr, len);
+ return len;
+}
+
+/**
+ * xdr_stream_decode_opaque_inline - Decode variable length opaque xdr data
+ * @xdr: pointer to xdr_stream
+ * @ptr: location to store pointer to opaque data
+ *
+ * Note: the pointer stored in @ptr cannot be assumed valid after the XDR
+ * buffer has been destroyed, or even after calling xdr_inline_decode()
+ * on @xdr. It is therefore expected that the object it points to should
+ * be processed immediately.
+ *
+ * Return values:
+ * On success, returns size of object stored in *@ptr
+ * %-ENOBUFS on XDR buffer overflow
+ */
+static inline ssize_t
+xdr_stream_decode_opaque_inline(struct xdr_stream *xdr, void **ptr)
+{
+ __be32 *p;
+ __u32 len;
+
+ if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0))
+ return -ENOBUFS;
+ if (len != 0) {
+ p = xdr_inline_decode(xdr, len);
+ if (unlikely(!p))
+ return -ENOBUFS;
+ *ptr = p;
+ } else
+ *ptr = NULL;
+ return len;
+}
#endif /* __KERNEL__ */

#endif /* _SUNRPC_XDR_H_ */
--
2.9.3