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From: Christoph Hellwig <hch@lst.de>
To: Ido Schimmel <idosch@idosch.org>
Cc: Christoph Hellwig <hch@lst.de>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
	Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
	Eric Dumazet <edumazet@google.com>,
	linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org,
	netdev@vger.kernel.org, bpf@vger.kernel.org,
	netfilter-devel@vger.kernel.org, coreteam@netfilter.org,
	linux-sctp@vger.kernel.org, linux-hams@vger.kernel.org,
	linux-bluetooth@vger.kernel.org,
	bridge@lists.linux-foundation.org, linux-can@vger.kernel.org,
	dccp@vger.kernel.org, linux-decnet-user@lists.sourceforge.net,
	linux-wpan@vger.kernel.org, linux-s390@vger.kernel.org,
	mptcp@lists.01.org, lvs-devel@vger.kernel.org,
	rds-devel@oss.oracle.com, linux-afs@lists.infradead.org,
	tipc-discussion@lists.sourceforge.net, linux-x25@vger.kernel.org
Subject: Re: [PATCH 19/26] net/ipv6: switch ipv6_flowlabel_opt to sockptr_t
Date: Mon, 27 Jul 2020 18:15:55 +0200	[thread overview]
Message-ID: <20200727161555.GA7817@lst.de> (raw)
In-Reply-To: <20200727133331.GA1851348@shredder>

I have to admit I didn't spot the difference between the good and the
bad output even after trying hard..

But can you try the patch below?

---
From cce2d2e1b43ecee5f4af7cf116808b74b330080f Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Mon, 27 Jul 2020 17:42:27 +0200
Subject: net: remove sockptr_advance

sockptr_advance never properly worked.  Replace it with _offset variants
of copy_from_sockptr and copy_to_sockptr.

Fixes: ba423fdaa589 ("net: add a new sockptr_t type")
Reported-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reported-by: Ido Schimmel <idosch@idosch.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/crypto/chelsio/chtls/chtls_main.c | 12 +++++-----
 include/linux/sockptr.h                   | 27 +++++++++++------------
 net/dccp/proto.c                          |  5 ++---
 net/ipv4/netfilter/arp_tables.c           |  8 +++----
 net/ipv4/netfilter/ip_tables.c            |  8 +++----
 net/ipv4/tcp.c                            |  5 +++--
 net/ipv6/ip6_flowlabel.c                  | 11 ++++-----
 net/ipv6/netfilter/ip6_tables.c           |  8 +++----
 net/netfilter/x_tables.c                  |  7 +++---
 net/tls/tls_main.c                        |  6 ++---
 10 files changed, 49 insertions(+), 48 deletions(-)

diff --git a/drivers/crypto/chelsio/chtls/chtls_main.c b/drivers/crypto/chelsio/chtls/chtls_main.c
index c3058dcdb33c5c..66d247efd5615b 100644
--- a/drivers/crypto/chelsio/chtls/chtls_main.c
+++ b/drivers/crypto/chelsio/chtls/chtls_main.c
@@ -525,9 +525,9 @@ static int do_chtls_setsockopt(struct sock *sk, int optname,
 		/* Obtain version and type from previous copy */
 		crypto_info[0] = tmp_crypto_info;
 		/* Now copy the following data */
-		sockptr_advance(optval, sizeof(*crypto_info));
-		rc = copy_from_sockptr((char *)crypto_info + sizeof(*crypto_info),
-				optval,
+		rc = copy_from_sockptr_offset((char *)crypto_info +
+				sizeof(*crypto_info),
+				optval, sizeof(*crypto_info),
 				sizeof(struct tls12_crypto_info_aes_gcm_128)
 				- sizeof(*crypto_info));
 
@@ -542,9 +542,9 @@ static int do_chtls_setsockopt(struct sock *sk, int optname,
 	}
 	case TLS_CIPHER_AES_GCM_256: {
 		crypto_info[0] = tmp_crypto_info;
-		sockptr_advance(optval, sizeof(*crypto_info));
-		rc = copy_from_sockptr((char *)crypto_info + sizeof(*crypto_info),
-				    optval,
+		rc = copy_from_sockptr_offset((char *)crypto_info +
+				sizeof(*crypto_info),
+				optval, sizeof(*crypto_info),
 				sizeof(struct tls12_crypto_info_aes_gcm_256)
 				- sizeof(*crypto_info));
 
diff --git a/include/linux/sockptr.h b/include/linux/sockptr.h
index b13ea1422f93a5..9e6c81d474cba8 100644
--- a/include/linux/sockptr.h
+++ b/include/linux/sockptr.h
@@ -69,19 +69,26 @@ static inline bool sockptr_is_null(sockptr_t sockptr)
 	return !sockptr.user;
 }
 
-static inline int copy_from_sockptr(void *dst, sockptr_t src, size_t size)
+static inline int copy_from_sockptr_offset(void *dst, sockptr_t src,
+		size_t offset, size_t size)
 {
 	if (!sockptr_is_kernel(src))
-		return copy_from_user(dst, src.user, size);
-	memcpy(dst, src.kernel, size);
+		return copy_from_user(dst, src.user + offset, size);
+	memcpy(dst, src.kernel + offset, size);
 	return 0;
 }
 
-static inline int copy_to_sockptr(sockptr_t dst, const void *src, size_t size)
+static inline int copy_from_sockptr(void *dst, sockptr_t src, size_t size)
+{
+	return copy_from_sockptr_offset(dst, src, 0, size);
+}
+
+static inline int copy_to_sockptr_offset(sockptr_t dst, size_t offset,
+		const void *src, size_t size)
 {
 	if (!sockptr_is_kernel(dst))
-		return copy_to_user(dst.user, src, size);
-	memcpy(dst.kernel, src, size);
+		return copy_to_user(dst.user + offset, src, size);
+	memcpy(dst.kernel + offset, src, size);
 	return 0;
 }
 
@@ -112,14 +119,6 @@ static inline void *memdup_sockptr_nul(sockptr_t src, size_t len)
 	return p;
 }
 
-static inline void sockptr_advance(sockptr_t sockptr, size_t len)
-{
-	if (sockptr_is_kernel(sockptr))
-		sockptr.kernel += len;
-	else
-		sockptr.user += len;
-}
-
 static inline long strncpy_from_sockptr(char *dst, sockptr_t src, size_t count)
 {
 	if (sockptr_is_kernel(src)) {
diff --git a/net/dccp/proto.c b/net/dccp/proto.c
index 2e9e8449698fb4..d148ab1530e57b 100644
--- a/net/dccp/proto.c
+++ b/net/dccp/proto.c
@@ -426,9 +426,8 @@ static int dccp_setsockopt_service(struct sock *sk, const __be32 service,
 			return -ENOMEM;
 
 		sl->dccpsl_nr = optlen / sizeof(u32) - 1;
-		sockptr_advance(optval, sizeof(service));
-		if (copy_from_sockptr(sl->dccpsl_list, optval,
-				      optlen - sizeof(service)) ||
+		if (copy_from_sockptr_offset(sl->dccpsl_list, optval,
+				sizeof(service), optlen - sizeof(service)) ||
 		    dccp_list_has_service(sl, DCCP_SERVICE_INVALID_VALUE)) {
 			kfree(sl);
 			return -EFAULT;
diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c
index 9a1567dbc022b6..d1e04d2b5170ec 100644
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -971,8 +971,8 @@ static int do_replace(struct net *net, sockptr_t arg, unsigned int len)
 		return -ENOMEM;
 
 	loc_cpu_entry = newinfo->entries;
-	sockptr_advance(arg, sizeof(tmp));
-	if (copy_from_sockptr(loc_cpu_entry, arg, tmp.size) != 0) {
+	if (copy_from_sockptr_offset(loc_cpu_entry, arg, sizeof(tmp),
+			tmp.size) != 0) {
 		ret = -EFAULT;
 		goto free_newinfo;
 	}
@@ -1267,8 +1267,8 @@ static int compat_do_replace(struct net *net, sockptr_t arg, unsigned int len)
 		return -ENOMEM;
 
 	loc_cpu_entry = newinfo->entries;
-	sockptr_advance(arg, sizeof(tmp));
-	if (copy_from_sockptr(loc_cpu_entry, arg, tmp.size) != 0) {
+	if (copy_from_sockptr_offset(loc_cpu_entry, arg, sizeof(tmp),
+			tmp.size) != 0) {
 		ret = -EFAULT;
 		goto free_newinfo;
 	}
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index f2a9680303d8c0..f15bc21d730164 100644
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -1126,8 +1126,8 @@ do_replace(struct net *net, sockptr_t arg, unsigned int len)
 		return -ENOMEM;
 
 	loc_cpu_entry = newinfo->entries;
-	sockptr_advance(arg, sizeof(tmp));
-	if (copy_from_sockptr(loc_cpu_entry, arg, tmp.size) != 0) {
+	if (copy_from_sockptr_offset(loc_cpu_entry, arg, sizeof(tmp),
+			tmp.size) != 0) {
 		ret = -EFAULT;
 		goto free_newinfo;
 	}
@@ -1508,8 +1508,8 @@ compat_do_replace(struct net *net, sockptr_t arg, unsigned int len)
 		return -ENOMEM;
 
 	loc_cpu_entry = newinfo->entries;
-	sockptr_advance(arg, sizeof(tmp));
-	if (copy_from_sockptr(loc_cpu_entry, arg, tmp.size) != 0) {
+	if (copy_from_sockptr_offset(loc_cpu_entry, arg, sizeof(tmp),
+			tmp.size) != 0) {
 		ret = -EFAULT;
 		goto free_newinfo;
 	}
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 27de9380ed140e..4afec552f211b9 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2801,12 +2801,13 @@ static int tcp_repair_options_est(struct sock *sk, sockptr_t optbuf,
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 	struct tcp_repair_opt opt;
+	size_t offset = 0;
 
 	while (len >= sizeof(opt)) {
-		if (copy_from_sockptr(&opt, optbuf, sizeof(opt)))
+		if (copy_from_sockptr_offset(&opt, optbuf, offset, sizeof(opt)))
 			return -EFAULT;
 
-		sockptr_advance(optbuf, sizeof(opt));
+		offset += sizeof(opt);
 		len -= sizeof(opt);
 
 		switch (opt.opt_code) {
diff --git a/net/ipv6/ip6_flowlabel.c b/net/ipv6/ip6_flowlabel.c
index 215b6f5e733ec9..2d655260dedc75 100644
--- a/net/ipv6/ip6_flowlabel.c
+++ b/net/ipv6/ip6_flowlabel.c
@@ -401,8 +401,8 @@ fl_create(struct net *net, struct sock *sk, struct in6_flowlabel_req *freq,
 		memset(fl->opt, 0, sizeof(*fl->opt));
 		fl->opt->tot_len = sizeof(*fl->opt) + olen;
 		err = -EFAULT;
-		sockptr_advance(optval, CMSG_ALIGN(sizeof(*freq)));
-		if (copy_from_sockptr(fl->opt + 1, optval, olen))
+		if (copy_from_sockptr_offset(fl->opt + 1, optval,
+				CMSG_ALIGN(sizeof(*freq)), olen))
 			goto done;
 
 		msg.msg_controllen = olen;
@@ -703,9 +703,10 @@ static int ipv6_flowlabel_get(struct sock *sk, struct in6_flowlabel_req *freq,
 		goto recheck;
 
 	if (!freq->flr_label) {
-		sockptr_advance(optval,
-				offsetof(struct in6_flowlabel_req, flr_label));
-		if (copy_to_sockptr(optval, &fl->label, sizeof(fl->label))) {
+		size_t offset = offsetof(struct in6_flowlabel_req, flr_label);
+
+		if (copy_to_sockptr_offset(optval, offset, &fl->label,
+				sizeof(fl->label))) {
 			/* Intentionally ignore fault. */
 		}
 	}
diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c
index 1d52957a413f4a..2e2119bfcf1373 100644
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -1143,8 +1143,8 @@ do_replace(struct net *net, sockptr_t arg, unsigned int len)
 		return -ENOMEM;
 
 	loc_cpu_entry = newinfo->entries;
-	sockptr_advance(arg, sizeof(tmp));
-	if (copy_from_sockptr(loc_cpu_entry, arg, tmp.size) != 0) {
+	if (copy_from_sockptr_offset(loc_cpu_entry, arg, sizeof(tmp),
+			tmp.size) != 0) {
 		ret = -EFAULT;
 		goto free_newinfo;
 	}
@@ -1517,8 +1517,8 @@ compat_do_replace(struct net *net, sockptr_t arg, unsigned int len)
 		return -ENOMEM;
 
 	loc_cpu_entry = newinfo->entries;
-	sockptr_advance(arg, sizeof(tmp));
-	if (copy_from_sockptr(loc_cpu_entry, arg, tmp.size) != 0) {
+	if (copy_from_sockptr_offset(loc_cpu_entry, arg, sizeof(tmp),
+			tmp.size) != 0) {
 		ret = -EFAULT;
 		goto free_newinfo;
 	}
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index b97eb4b538fd4e..91bf6635ea9ee4 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -1050,6 +1050,7 @@ EXPORT_SYMBOL_GPL(xt_check_target);
 void *xt_copy_counters(sockptr_t arg, unsigned int len,
 		       struct xt_counters_info *info)
 {
+	size_t offset;
 	void *mem;
 	u64 size;
 
@@ -1067,7 +1068,7 @@ void *xt_copy_counters(sockptr_t arg, unsigned int len,
 
 		memcpy(info->name, compat_tmp.name, sizeof(info->name) - 1);
 		info->num_counters = compat_tmp.num_counters;
-		sockptr_advance(arg, sizeof(compat_tmp));
+		offset = sizeof(compat_tmp);
 	} else
 #endif
 	{
@@ -1078,7 +1079,7 @@ void *xt_copy_counters(sockptr_t arg, unsigned int len,
 		if (copy_from_sockptr(info, arg, sizeof(*info)) != 0)
 			return ERR_PTR(-EFAULT);
 
-		sockptr_advance(arg, sizeof(*info));
+		offset = sizeof(*info);
 	}
 	info->name[sizeof(info->name) - 1] = '\0';
 
@@ -1092,7 +1093,7 @@ void *xt_copy_counters(sockptr_t arg, unsigned int len,
 	if (!mem)
 		return ERR_PTR(-ENOMEM);
 
-	if (copy_from_sockptr(mem, arg, len) == 0)
+	if (copy_from_sockptr_offset(mem, arg, offset, len) == 0)
 		return mem;
 
 	vfree(mem);
diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
index d77f7d821130db..bbc52b088d2968 100644
--- a/net/tls/tls_main.c
+++ b/net/tls/tls_main.c
@@ -522,9 +522,9 @@ static int do_tls_setsockopt_conf(struct sock *sk, sockptr_t optval,
 		goto err_crypto_info;
 	}
 
-	sockptr_advance(optval, sizeof(*crypto_info));
-	rc = copy_from_sockptr(crypto_info + 1, optval,
-			       optlen - sizeof(*crypto_info));
+	rc = copy_from_sockptr_offset(crypto_info + 1, optval,
+				      sizeof(*crypto_info),
+				      optlen - sizeof(*crypto_info));
 	if (rc) {
 		rc = -EFAULT;
 		goto err_crypto_info;
-- 
2.27.0


  reply	other threads:[~2020-07-27 16:16 UTC|newest]

Thread overview: 64+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-23  6:08 get rid of the address_space override in setsockopt v2 Christoph Hellwig
2020-07-23  6:08 ` [PATCH 01/26] bpfilter: fix up a sparse annotation Christoph Hellwig
2020-07-23 11:14   ` Luc Van Oostenryck
2020-07-23  6:08 ` [PATCH 02/26] net/bpfilter: split __bpfilter_process_sockopt Christoph Hellwig
2020-07-23  6:08 ` [PATCH 03/26] bpfilter: reject kernel addresses Christoph Hellwig
2020-07-23 14:42   ` David Laight
2020-07-23 14:44     ` 'Christoph Hellwig'
2020-07-23 14:56       ` David Laight
2020-07-23  6:08 ` [PATCH 04/26] net: add a new sockptr_t type Christoph Hellwig
2020-07-23 15:40   ` Jan Engelhardt
2020-07-23 16:40   ` Eric Dumazet
2020-07-23 16:44     ` Christoph Hellwig
2020-07-23  6:08 ` [PATCH 05/26] net: switch copy_bpf_fprog_from_user to sockptr_t Christoph Hellwig
2020-07-23  6:08 ` [PATCH 06/26] net: switch sock_setbindtodevice " Christoph Hellwig
2020-07-23  6:08 ` [PATCH 07/26] net: switch sock_set_timeout " Christoph Hellwig
2020-07-23  6:08 ` [PATCH 08/26] " Christoph Hellwig
2020-07-23  8:39   ` [MPTCP] " Matthieu Baerts
2020-07-23  6:08 ` [PATCH 09/26] net/xfrm: switch xfrm_user_policy " Christoph Hellwig
2020-07-23  6:08 ` [PATCH 10/26] netfilter: remove the unused user argument to do_update_counters Christoph Hellwig
2020-07-23  6:08 ` [PATCH 11/26] netfilter: switch xt_copy_counters to sockptr_t Christoph Hellwig
2020-07-23  6:08 ` [PATCH 12/26] netfilter: switch nf_setsockopt " Christoph Hellwig
2020-07-27 15:03   ` Jason A. Donenfeld
2020-07-27 15:06     ` Christoph Hellwig
2020-07-27 16:16       ` Jason A. Donenfeld
2020-07-27 16:23         ` Christoph Hellwig
2020-07-28  8:07           ` David Laight
2020-07-28  8:17             ` Jason A. Donenfeld
2020-07-27 16:16     ` Christoph Hellwig
2020-07-27 16:21       ` Jason A. Donenfeld
2020-07-23  6:08 ` [PATCH 13/26] bpfilter: switch bpfilter_ip_set_sockopt " Christoph Hellwig
2020-07-23 11:16   ` David Laight
2020-07-23 11:44     ` 'Christoph Hellwig'
2020-07-23  6:08 ` [PATCH 14/26] net/ipv4: switch ip_mroute_setsockopt " Christoph Hellwig
2020-07-23  6:08 ` [PATCH 15/26] net/ipv4: merge ip_options_get and ip_options_get_from_user Christoph Hellwig
2020-07-23  6:08 ` [PATCH 16/26] net/ipv4: switch do_ip_setsockopt to sockptr_t Christoph Hellwig
2020-07-23  6:08 ` [PATCH 17/26] net/ipv6: switch ip6_mroute_setsockopt " Christoph Hellwig
2020-07-23  6:09 ` [PATCH 18/26] net/ipv6: split up ipv6_flowlabel_opt Christoph Hellwig
2020-07-23  6:09 ` [PATCH 19/26] net/ipv6: switch ipv6_flowlabel_opt to sockptr_t Christoph Hellwig
2020-07-27 12:15   ` Ido Schimmel
2020-07-27 13:00     ` Christoph Hellwig
2020-07-27 13:33       ` Ido Schimmel
2020-07-27 16:15         ` Christoph Hellwig [this message]
2020-07-27 18:22           ` Ido Schimmel
2020-07-27 13:24     ` David Laight
2020-07-23  6:09 ` [PATCH 20/26] net/ipv6: factor out a ipv6_set_opt_hdr helper Christoph Hellwig
2020-07-23  6:09 ` [PATCH 21/26] net/ipv6: switch do_ipv6_setsockopt to sockptr_t Christoph Hellwig
2020-07-23  6:09 ` [PATCH 22/26] net/udp: switch udp_lib_setsockopt " Christoph Hellwig
2020-07-23  6:09 ` [PATCH 23/26] net/tcp: switch ->md5_parse " Christoph Hellwig
2020-07-23  6:09 ` [PATCH 24/26] net/tcp: switch do_tcp_setsockopt " Christoph Hellwig
2020-07-23  6:09 ` [PATCH 25/26] net: pass a sockptr_t into ->setsockopt Christoph Hellwig
2020-07-23  8:39   ` [MPTCP] " Matthieu Baerts
2020-08-06 22:21   ` Eric Dumazet
2020-08-07  7:21     ` Christoph Hellwig
2020-08-07  9:18     ` David Laight
2020-08-07 18:29       ` Eric Dumazet
2020-08-08 13:54         ` David Laight
2020-07-23  6:09 ` [PATCH 26/26] net: optimize the sockptr_t for unified kernel/user address spaces Christoph Hellwig
2020-07-24 22:43 ` get rid of the address_space override in setsockopt v2 David Miller
2020-07-26  7:03   ` Christoph Hellwig
2020-07-26  7:08     ` Andreas Schwab
2020-07-26  7:46     ` David Miller
2020-07-27  9:51   ` David Laight
2020-07-27 13:48     ` Al Viro
2020-07-27 14:09       ` David Laight

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