From 6370cc3bbd8a0f9bf975b013781243ab147876c6 Mon Sep 17 00:00:00 2001
From: Aleksandr Nogikh <nogikh@google.com>
Date: Thu, 29 Oct 2020 17:36:19 +0000
Subject: net: add kcov handle to skb extensions

Remote KCOV coverage collection enables coverage-guided fuzzing of the
code that is not reachable during normal system call execution. It is
especially helpful for fuzzing networking subsystems, where it is
common to perform packet handling in separate work queues even for the
packets that originated directly from the user space.

Enable coverage-guided frame injection by adding kcov remote handle to
skb extensions. Default initialization in __alloc_skb and
__build_skb_around ensures that no socket buffer that was generated
during a system call will be missed.

Code that is of interest and that performs packet processing should be
annotated with kcov_remote_start()/kcov_remote_stop().

An alternative approach is to determine kcov_handle solely on the
basis of the device/interface that received the specific socket
buffer. However, in this case it would be impossible to distinguish
between packets that originated during normal background network
processes or were intentionally injected from the user space.

Signed-off-by: Aleksandr Nogikh <nogikh@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 lib/Kconfig.debug | 1 +
 1 file changed, 1 insertion(+)

(limited to 'lib')

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index d7a7bc3b6098..d171a032db78 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1870,6 +1870,7 @@ config KCOV
 	depends on CC_HAS_SANCOV_TRACE_PC || GCC_PLUGINS
 	select DEBUG_FS
 	select GCC_PLUGIN_SANCOV if !CC_HAS_SANCOV_TRACE_PC
+	select SKB_EXTENSIONS
 	help
 	  KCOV exposes kernel code coverage information in a form suitable
 	  for coverage-guided fuzzing (randomized testing).
-- 
cgit v1.2.3


From 5f9ae91f7c0dbbc4195e2a6c8eedcaeb5b9e4cbb Mon Sep 17 00:00:00 2001
From: Andrii Nakryiko <andrii@kernel.org>
Date: Mon, 9 Nov 2020 17:19:30 -0800
Subject: kbuild: Build kernel module BTFs if BTF is enabled and pahole
 supports it

Detect if pahole supports split BTF generation, and generate BTF for each
selected kernel module, if it does. This is exposed to Makefiles and C code as
CONFIG_DEBUG_INFO_BTF_MODULES flag.

Kernel module BTF has to be re-generated if either vmlinux's BTF changes or
module's .ko changes. To achieve that, I needed a helper similar to
if_changed, but that would allow to filter out vmlinux from the list of
updated dependencies for .ko building. I've put it next to the only place that
uses and needs it, but it might be a better idea to just add it along the
other if_changed variants into scripts/Kbuild.include.

Each kernel module's BTF deduplication is pretty fast, as it does only
incremental BTF deduplication on top of already deduplicated vmlinux BTF. To
show the added build time, I've first ran make only just built kernel (to
establish the baseline) and then forced only BTF re-generation, without
regenerating .ko files. The build was performed with -j60 parallelization on
56-core machine. The final time also includes bzImage building, so it's not
a pure BTF overhead.

$ time make -j60
...
make -j60  27.65s user 10.96s system 782% cpu 4.933 total
$ touch ~/linux-build/default/vmlinux && time make -j60
...
make -j60  123.69s user 27.85s system 1566% cpu 9.675 total

So 4.6 seconds real time, with noticeable part spent in compressed vmlinux and
bzImage building.

To show size savings, I've built my kernel configuration with about 700 kernel
modules with full BTF per each kernel module (without deduplicating against
vmlinux) and with split BTF against deduplicated vmlinux (approach in this
patch). Below are top 10 modules with biggest BTF sizes. And total size of BTF
data across all kernel modules.

It shows that split BTF "compresses" 115MB down to 5MB total. And the biggest
kernel modules get a downsize from 500-570KB down to 200-300KB.

FULL BTF
========

$ for f in $(find . -name '*.ko'); do size -A -d $f | grep BTF | awk '{print $2}'; done | awk '{ s += $1 } END { print s }'
115710691

$ for f in $(find . -name '*.ko'); do printf "%s %d\n" $f $(size -A -d $f | grep BTF | awk '{print $2}'); done | sort -nr -k2 | head -n10
./drivers/gpu/drm/i915/i915.ko 570570
./drivers/net/ethernet/mellanox/mlx5/core/mlx5_core.ko 520240
./drivers/gpu/drm/radeon/radeon.ko 503849
./drivers/infiniband/hw/mlx5/mlx5_ib.ko 491777
./fs/xfs/xfs.ko 411544
./drivers/net/ethernet/intel/i40e/i40e.ko 403904
./drivers/net/ethernet/broadcom/bnx2x/bnx2x.ko 398754
./drivers/infiniband/core/ib_core.ko 397224
./fs/cifs/cifs.ko 386249
./fs/nfsd/nfsd.ko 379738

SPLIT BTF
=========

$ for f in $(find . -name '*.ko'); do size -A -d $f | grep BTF | awk '{print $2}'; done | awk '{ s += $1 } END { print s }'
5194047

$ for f in $(find . -name '*.ko'); do printf "%s %d\n" $f $(size -A -d $f | grep BTF | awk '{print $2}'); done | sort -nr -k2 | head -n10
./drivers/gpu/drm/i915/i915.ko 293206
./drivers/gpu/drm/radeon/radeon.ko 282103
./fs/xfs/xfs.ko 222150
./drivers/net/ethernet/mellanox/mlx5/core/mlx5_core.ko 198503
./drivers/infiniband/hw/mlx5/mlx5_ib.ko 198356
./drivers/net/ethernet/broadcom/bnx2x/bnx2x.ko 113444
./fs/cifs/cifs.ko 109379
./arch/x86/kvm/kvm.ko 100225
./drivers/gpu/drm/drm.ko 94827
./drivers/infiniband/core/ib_core.ko 91188

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201110011932.3201430-4-andrii@kernel.org
---
 lib/Kconfig.debug         |  9 +++++++++
 scripts/Makefile.modfinal | 20 ++++++++++++++++++--
 2 files changed, 27 insertions(+), 2 deletions(-)

(limited to 'lib')

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index d7a7bc3b6098..1e78faaf20a5 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -274,6 +274,15 @@ config DEBUG_INFO_BTF
 	  Turning this on expects presence of pahole tool, which will convert
 	  DWARF type info into equivalent deduplicated BTF type info.
 
+config PAHOLE_HAS_SPLIT_BTF
+	def_bool $(success, test `$(PAHOLE) --version | sed -E 's/v([0-9]+)\.([0-9]+)/\1\2/'` -ge "119")
+
+config DEBUG_INFO_BTF_MODULES
+	def_bool y
+	depends on DEBUG_INFO_BTF && MODULES && PAHOLE_HAS_SPLIT_BTF
+	help
+	  Generate compact split BTF type information for kernel modules.
+
 config GDB_SCRIPTS
 	bool "Provide GDB scripts for kernel debugging"
 	help
diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal
index ae01baf96f4e..02b892421f7a 100644
--- a/scripts/Makefile.modfinal
+++ b/scripts/Makefile.modfinal
@@ -6,6 +6,7 @@
 PHONY := __modfinal
 __modfinal:
 
+include include/config/auto.conf
 include $(srctree)/scripts/Kbuild.include
 
 # for c_flags
@@ -36,8 +37,23 @@ quiet_cmd_ld_ko_o = LD [M]  $@
 		-T scripts/module.lds -o $@ $(filter %.o, $^);		\
 	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
 
-$(modules): %.ko: %.o %.mod.o scripts/module.lds FORCE
-	+$(call if_changed,ld_ko_o)
+quiet_cmd_btf_ko = BTF [M] $@
+      cmd_btf_ko = LLVM_OBJCOPY=$(OBJCOPY) $(PAHOLE) -J --btf_base vmlinux $@
+
+# Same as newer-prereqs, but allows to exclude specified extra dependencies
+newer_prereqs_except = $(filter-out $(PHONY) $(1),$?)
+
+# Same as if_changed, but allows to exclude specified extra dependencies
+if_changed_except = $(if $(call newer_prereqs_except,$(2))$(cmd-check),      \
+	$(cmd);                                                              \
+	printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:)
+
+# Re-generate module BTFs if either module's .ko or vmlinux changed
+$(modules): %.ko: %.o %.mod.o scripts/module.lds vmlinux FORCE
+	+$(call if_changed_except,ld_ko_o,vmlinux)
+ifdef CONFIG_DEBUG_INFO_BTF_MODULES
+	+$(if $(newer-prereqs),$(call cmd,btf_ko))
+endif
 
 targets += $(modules) $(modules:.ko=.mod.o)
 
-- 
cgit v1.2.3


From 85ce50d337d10a6fd328fa70b0a15543bf5c0f64 Mon Sep 17 00:00:00 2001
From: Randy Dunlap <rdunlap@infradead.org>
Date: Tue, 10 Nov 2020 09:57:46 -0800
Subject: net: kcov: don't select SKB_EXTENSIONS when there is no NET

Fix kconfig warning when CONFIG_NET is not set/enabled:

WARNING: unmet direct dependencies detected for SKB_EXTENSIONS
  Depends on [n]: NET [=n]
  Selected by [y]:
  - KCOV [=y] && ARCH_HAS_KCOV [=y] && (CC_HAS_SANCOV_TRACE_PC [=y] || GCC_PLUGINS [=n])

Fixes: 6370cc3bbd8a ("net: add kcov handle to skb extensions")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Aleksandr Nogikh <nogikh@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20201110175746.11437-1-rdunlap@infradead.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 lib/Kconfig.debug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'lib')

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index dd052a272fa7..fc6e120045b0 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1870,7 +1870,7 @@ config KCOV
 	depends on CC_HAS_SANCOV_TRACE_PC || GCC_PLUGINS
 	select DEBUG_FS
 	select GCC_PLUGIN_SANCOV if !CC_HAS_SANCOV_TRACE_PC
-	select SKB_EXTENSIONS
+	select SKB_EXTENSIONS if NET
 	help
 	  KCOV exposes kernel code coverage information in a form suitable
 	  for coverage-guided fuzzing (randomized testing).
-- 
cgit v1.2.3


From 8eeb99bc81bc1cb3d5e5323d9a82d8392e3a27b4 Mon Sep 17 00:00:00 2001
From: Francis Laniel <laniel_francis@privacyrequired.com>
Date: Sun, 15 Nov 2020 18:08:04 +0100
Subject: Fix unefficient call to memset before memcpu in nla_strlcpy.

Before this commit, nla_strlcpy first memseted dst to 0 then wrote src into it.
This is inefficient because bytes whom number is less than src length are written
twice.

This patch solves this issue by first writing src into dst then fill dst with
0's.
Note that, in the case where src length is higher than dst, only 0 is written.
Otherwise there are as many 0's written to fill dst.

For example, if src is "foo\0" and dst is 5 bytes long, the result will be:
1. "fooGG" after memcpy (G means garbage).
2. "foo\0\0" after memset.

Signed-off-by: Francis Laniel <laniel_francis@privacyrequired.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 lib/nlattr.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

(limited to 'lib')

diff --git a/lib/nlattr.c b/lib/nlattr.c
index 74019c8ebf6b..07156e581997 100644
--- a/lib/nlattr.c
+++ b/lib/nlattr.c
@@ -731,8 +731,9 @@ size_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize)
 	if (dstsize > 0) {
 		size_t len = (srclen >= dstsize) ? dstsize - 1 : srclen;
 
-		memset(dst, 0, dstsize);
 		memcpy(dst, src, len);
+		/* Zero pad end of dst. */
+		memset(dst + len, 0, dstsize - len);
 	}
 
 	return srclen;
-- 
cgit v1.2.3


From 9ca718743ad8402958637bfc196d7b62371a1b9f Mon Sep 17 00:00:00 2001
From: Francis Laniel <laniel_francis@privacyrequired.com>
Date: Sun, 15 Nov 2020 18:08:05 +0100
Subject: Modify return value of nla_strlcpy to match that of strscpy.

nla_strlcpy now returns -E2BIG if src was truncated when written to dst.
It also returns this error value if dstsize is 0 or higher than INT_MAX.

For example, if src is "foo\0" and dst is 3 bytes long, the result will be:
1. "foG" after memcpy (G means garbage).
2. "fo\0" after memset.
3. -E2BIG is returned because src was not completely written into dst.

The callers of nla_strlcpy were modified to take into account this modification.

Signed-off-by: Francis Laniel <laniel_francis@privacyrequired.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 include/net/netlink.h |  2 +-
 include/net/pkt_cls.h |  2 +-
 lib/nlattr.c          | 39 +++++++++++++++++++++++++--------------
 net/sched/act_api.c   |  2 +-
 net/sched/cls_api.c   |  2 +-
 net/sched/sch_api.c   |  2 +-
 6 files changed, 30 insertions(+), 19 deletions(-)

(limited to 'lib')

diff --git a/include/net/netlink.h b/include/net/netlink.h
index 7356f41d23ba..446ca182e13d 100644
--- a/include/net/netlink.h
+++ b/include/net/netlink.h
@@ -506,7 +506,7 @@ int __nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head,
 		struct netlink_ext_ack *extack);
 int nla_policy_len(const struct nla_policy *, int);
 struct nlattr *nla_find(const struct nlattr *head, int len, int attrtype);
-size_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize);
+ssize_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize);
 char *nla_strdup(const struct nlattr *nla, gfp_t flags);
 int nla_memcpy(void *dest, const struct nlattr *src, int count);
 int nla_memcmp(const struct nlattr *nla, const void *data, size_t size);
diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h
index d4d461236351..db9a828f4f4f 100644
--- a/include/net/pkt_cls.h
+++ b/include/net/pkt_cls.h
@@ -512,7 +512,7 @@ tcf_change_indev(struct net *net, struct nlattr *indev_tlv,
 	char indev[IFNAMSIZ];
 	struct net_device *dev;
 
-	if (nla_strlcpy(indev, indev_tlv, IFNAMSIZ) >= IFNAMSIZ) {
+	if (nla_strlcpy(indev, indev_tlv, IFNAMSIZ) < 0) {
 		NL_SET_ERR_MSG_ATTR(extack, indev_tlv,
 				    "Interface name too long");
 		return -EINVAL;
diff --git a/lib/nlattr.c b/lib/nlattr.c
index 07156e581997..447182543c03 100644
--- a/lib/nlattr.c
+++ b/lib/nlattr.c
@@ -710,33 +710,44 @@ EXPORT_SYMBOL(nla_find);
 
 /**
  * nla_strlcpy - Copy string attribute payload into a sized buffer
- * @dst: where to copy the string to
- * @nla: attribute to copy the string from
- * @dstsize: size of destination buffer
+ * @dst: Where to copy the string to.
+ * @nla: Attribute to copy the string from.
+ * @dstsize: Size of destination buffer.
  *
  * Copies at most dstsize - 1 bytes into the destination buffer.
- * The result is always a valid NUL-terminated string. Unlike
- * strlcpy the destination buffer is always padded out.
+ * Unlike strlcpy the destination buffer is always padded out.
  *
- * Returns the length of the source buffer.
+ * Return:
+ * * srclen - Returns @nla length (not including the trailing %NUL).
+ * * -E2BIG - If @dstsize is 0 or greater than U16_MAX or @nla length greater
+ *            than @dstsize.
  */
-size_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize)
+ssize_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize)
 {
 	size_t srclen = nla_len(nla);
 	char *src = nla_data(nla);
+	ssize_t ret;
+	size_t len;
+
+	if (dstsize == 0 || WARN_ON_ONCE(dstsize > U16_MAX))
+		return -E2BIG;
 
 	if (srclen > 0 && src[srclen - 1] == '\0')
 		srclen--;
 
-	if (dstsize > 0) {
-		size_t len = (srclen >= dstsize) ? dstsize - 1 : srclen;
-
-		memcpy(dst, src, len);
-		/* Zero pad end of dst. */
-		memset(dst + len, 0, dstsize - len);
+	if (srclen >= dstsize) {
+		len = dstsize - 1;
+		ret = -E2BIG;
+	} else {
+		len = srclen;
+		ret = len;
 	}
 
-	return srclen;
+	memcpy(dst, src, len);
+	/* Zero pad end of dst. */
+	memset(dst + len, 0, dstsize - len);
+
+	return ret;
 }
 EXPORT_SYMBOL(nla_strlcpy);
 
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index 60e1572ba606..fe540a89b16c 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -939,7 +939,7 @@ struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
 			NL_SET_ERR_MSG(extack, "TC action kind must be specified");
 			goto err_out;
 		}
-		if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ) {
+		if (nla_strlcpy(act_name, kind, IFNAMSIZ) < 0) {
 			NL_SET_ERR_MSG(extack, "TC action name too long");
 			goto err_out;
 		}
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index ba0715ee9eac..c2e9661e20d3 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -223,7 +223,7 @@ static inline u32 tcf_auto_prio(struct tcf_proto *tp)
 static bool tcf_proto_check_kind(struct nlattr *kind, char *name)
 {
 	if (kind)
-		return nla_strlcpy(name, kind, IFNAMSIZ) >= IFNAMSIZ;
+		return nla_strlcpy(name, kind, IFNAMSIZ) < 0;
 	memset(name, 0, IFNAMSIZ);
 	return false;
 }
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index 2a76a2f5ed88..05449286d889 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -1170,7 +1170,7 @@ static struct Qdisc *qdisc_create(struct net_device *dev,
 #ifdef CONFIG_MODULES
 	if (ops == NULL && kind != NULL) {
 		char name[IFNAMSIZ];
-		if (nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
+		if (nla_strlcpy(name, kind, IFNAMSIZ) >= 0) {
 			/* We dropped the RTNL semaphore in order to
 			 * perform the module load.  So, even if we
 			 * succeeded in loading the module we have to
-- 
cgit v1.2.3


From 872f690341948b502c93318f806d821c56772c42 Mon Sep 17 00:00:00 2001
From: Francis Laniel <laniel_francis@privacyrequired.com>
Date: Sun, 15 Nov 2020 18:08:06 +0100
Subject: treewide: rename nla_strlcpy to nla_strscpy.

Calls to nla_strlcpy are now replaced by calls to nla_strscpy which is the new
name of this function.

Signed-off-by: Francis Laniel <laniel_francis@privacyrequired.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 drivers/infiniband/core/nldev.c            | 10 +++++-----
 drivers/net/can/vxcan.c                    |  4 ++--
 drivers/net/veth.c                         |  4 ++--
 include/linux/genl_magic_struct.h          |  2 +-
 include/net/netlink.h                      |  4 ++--
 include/net/pkt_cls.h                      |  2 +-
 kernel/taskstats.c                         |  2 +-
 lib/nlattr.c                               |  6 +++---
 net/core/fib_rules.c                       |  4 ++--
 net/core/rtnetlink.c                       | 12 ++++++------
 net/decnet/dn_dev.c                        |  2 +-
 net/ieee802154/nl-mac.c                    |  2 +-
 net/ipv4/devinet.c                         |  2 +-
 net/ipv4/fib_semantics.c                   |  2 +-
 net/ipv4/metrics.c                         |  2 +-
 net/netfilter/ipset/ip_set_hash_netiface.c |  4 ++--
 net/netfilter/nf_tables_api.c              |  6 +++---
 net/netfilter/nfnetlink_acct.c             |  2 +-
 net/netfilter/nfnetlink_cthelper.c         |  4 ++--
 net/netfilter/nft_ct.c                     |  2 +-
 net/netfilter/nft_log.c                    |  2 +-
 net/netlabel/netlabel_mgmt.c               |  2 +-
 net/nfc/netlink.c                          |  2 +-
 net/sched/act_api.c                        |  2 +-
 net/sched/act_ipt.c                        |  2 +-
 net/sched/act_simple.c                     |  4 ++--
 net/sched/cls_api.c                        |  2 +-
 net/sched/sch_api.c                        |  2 +-
 net/tipc/netlink_compat.c                  |  2 +-
 29 files changed, 49 insertions(+), 49 deletions(-)

(limited to 'lib')

diff --git a/drivers/infiniband/core/nldev.c b/drivers/infiniband/core/nldev.c
index 12d29d54a081..08366e254b1d 100644
--- a/drivers/infiniband/core/nldev.c
+++ b/drivers/infiniband/core/nldev.c
@@ -932,7 +932,7 @@ static int nldev_set_doit(struct sk_buff *skb, struct nlmsghdr *nlh,
 	if (tb[RDMA_NLDEV_ATTR_DEV_NAME]) {
 		char name[IB_DEVICE_NAME_MAX] = {};
 
-		nla_strlcpy(name, tb[RDMA_NLDEV_ATTR_DEV_NAME],
+		nla_strscpy(name, tb[RDMA_NLDEV_ATTR_DEV_NAME],
 			    IB_DEVICE_NAME_MAX);
 		if (strlen(name) == 0) {
 			err = -EINVAL;
@@ -1529,13 +1529,13 @@ static int nldev_newlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 	    !tb[RDMA_NLDEV_ATTR_LINK_TYPE] || !tb[RDMA_NLDEV_ATTR_NDEV_NAME])
 		return -EINVAL;
 
-	nla_strlcpy(ibdev_name, tb[RDMA_NLDEV_ATTR_DEV_NAME],
+	nla_strscpy(ibdev_name, tb[RDMA_NLDEV_ATTR_DEV_NAME],
 		    sizeof(ibdev_name));
 	if (strchr(ibdev_name, '%') || strlen(ibdev_name) == 0)
 		return -EINVAL;
 
-	nla_strlcpy(type, tb[RDMA_NLDEV_ATTR_LINK_TYPE], sizeof(type));
-	nla_strlcpy(ndev_name, tb[RDMA_NLDEV_ATTR_NDEV_NAME],
+	nla_strscpy(type, tb[RDMA_NLDEV_ATTR_LINK_TYPE], sizeof(type));
+	nla_strscpy(ndev_name, tb[RDMA_NLDEV_ATTR_NDEV_NAME],
 		    sizeof(ndev_name));
 
 	ndev = dev_get_by_name(sock_net(skb->sk), ndev_name);
@@ -1602,7 +1602,7 @@ static int nldev_get_chardev(struct sk_buff *skb, struct nlmsghdr *nlh,
 	if (err || !tb[RDMA_NLDEV_ATTR_CHARDEV_TYPE])
 		return -EINVAL;
 
-	nla_strlcpy(client_name, tb[RDMA_NLDEV_ATTR_CHARDEV_TYPE],
+	nla_strscpy(client_name, tb[RDMA_NLDEV_ATTR_CHARDEV_TYPE],
 		    sizeof(client_name));
 
 	if (tb[RDMA_NLDEV_ATTR_DEV_INDEX]) {
diff --git a/drivers/net/can/vxcan.c b/drivers/net/can/vxcan.c
index d6ba9426be4d..fa47bab510bb 100644
--- a/drivers/net/can/vxcan.c
+++ b/drivers/net/can/vxcan.c
@@ -186,7 +186,7 @@ static int vxcan_newlink(struct net *net, struct net_device *dev,
 	}
 
 	if (ifmp && tbp[IFLA_IFNAME]) {
-		nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
+		nla_strscpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
 		name_assign_type = NET_NAME_USER;
 	} else {
 		snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");
@@ -223,7 +223,7 @@ static int vxcan_newlink(struct net *net, struct net_device *dev,
 
 	/* register first device */
 	if (tb[IFLA_IFNAME])
-		nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
+		nla_strscpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
 	else
 		snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");
 
diff --git a/drivers/net/veth.c b/drivers/net/veth.c
index 8c737668008a..359d3ab33c4d 100644
--- a/drivers/net/veth.c
+++ b/drivers/net/veth.c
@@ -1329,7 +1329,7 @@ static int veth_newlink(struct net *src_net, struct net_device *dev,
 	}
 
 	if (ifmp && tbp[IFLA_IFNAME]) {
-		nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
+		nla_strscpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
 		name_assign_type = NET_NAME_USER;
 	} else {
 		snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");
@@ -1379,7 +1379,7 @@ static int veth_newlink(struct net *src_net, struct net_device *dev,
 		eth_hw_addr_random(dev);
 
 	if (tb[IFLA_IFNAME])
-		nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
+		nla_strscpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
 	else
 		snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");
 
diff --git a/include/linux/genl_magic_struct.h b/include/linux/genl_magic_struct.h
index eeae59d3ceb7..35d21fddaf2d 100644
--- a/include/linux/genl_magic_struct.h
+++ b/include/linux/genl_magic_struct.h
@@ -89,7 +89,7 @@ static inline int nla_put_u64_0pad(struct sk_buff *skb, int attrtype, u64 value)
 			nla_get_u64, nla_put_u64_0pad, false)
 #define __str_field(attr_nr, attr_flag, name, maxlen) \
 	__array(attr_nr, attr_flag, name, NLA_NUL_STRING, char, maxlen, \
-			nla_strlcpy, nla_put, false)
+			nla_strscpy, nla_put, false)
 #define __bin_field(attr_nr, attr_flag, name, maxlen) \
 	__array(attr_nr, attr_flag, name, NLA_BINARY, char, maxlen, \
 			nla_memcpy, nla_put, false)
diff --git a/include/net/netlink.h b/include/net/netlink.h
index 446ca182e13d..1ceec518ab49 100644
--- a/include/net/netlink.h
+++ b/include/net/netlink.h
@@ -142,7 +142,7 @@
  * Attribute Misc:
  *   nla_memcpy(dest, nla, count)	copy attribute into memory
  *   nla_memcmp(nla, data, size)	compare attribute with memory area
- *   nla_strlcpy(dst, nla, size)	copy attribute to a sized string
+ *   nla_strscpy(dst, nla, size)	copy attribute to a sized string
  *   nla_strcmp(nla, str)		compare attribute with string
  *
  * Attribute Parsing:
@@ -506,7 +506,7 @@ int __nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head,
 		struct netlink_ext_ack *extack);
 int nla_policy_len(const struct nla_policy *, int);
 struct nlattr *nla_find(const struct nlattr *head, int len, int attrtype);
-ssize_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize);
+ssize_t nla_strscpy(char *dst, const struct nlattr *nla, size_t dstsize);
 char *nla_strdup(const struct nlattr *nla, gfp_t flags);
 int nla_memcpy(void *dest, const struct nlattr *src, int count);
 int nla_memcmp(const struct nlattr *nla, const void *data, size_t size);
diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h
index db9a828f4f4f..133f9ad4d4f9 100644
--- a/include/net/pkt_cls.h
+++ b/include/net/pkt_cls.h
@@ -512,7 +512,7 @@ tcf_change_indev(struct net *net, struct nlattr *indev_tlv,
 	char indev[IFNAMSIZ];
 	struct net_device *dev;
 
-	if (nla_strlcpy(indev, indev_tlv, IFNAMSIZ) < 0) {
+	if (nla_strscpy(indev, indev_tlv, IFNAMSIZ) < 0) {
 		NL_SET_ERR_MSG_ATTR(extack, indev_tlv,
 				    "Interface name too long");
 		return -EINVAL;
diff --git a/kernel/taskstats.c b/kernel/taskstats.c
index a2802b6ff4bb..2b4898b4752e 100644
--- a/kernel/taskstats.c
+++ b/kernel/taskstats.c
@@ -346,7 +346,7 @@ static int parse(struct nlattr *na, struct cpumask *mask)
 	data = kmalloc(len, GFP_KERNEL);
 	if (!data)
 		return -ENOMEM;
-	nla_strlcpy(data, na, len);
+	nla_strscpy(data, na, len);
 	ret = cpulist_parse(data, mask);
 	kfree(data);
 	return ret;
diff --git a/lib/nlattr.c b/lib/nlattr.c
index 447182543c03..09aa181569e0 100644
--- a/lib/nlattr.c
+++ b/lib/nlattr.c
@@ -709,7 +709,7 @@ struct nlattr *nla_find(const struct nlattr *head, int len, int attrtype)
 EXPORT_SYMBOL(nla_find);
 
 /**
- * nla_strlcpy - Copy string attribute payload into a sized buffer
+ * nla_strscpy - Copy string attribute payload into a sized buffer
  * @dst: Where to copy the string to.
  * @nla: Attribute to copy the string from.
  * @dstsize: Size of destination buffer.
@@ -722,7 +722,7 @@ EXPORT_SYMBOL(nla_find);
  * * -E2BIG - If @dstsize is 0 or greater than U16_MAX or @nla length greater
  *            than @dstsize.
  */
-ssize_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize)
+ssize_t nla_strscpy(char *dst, const struct nlattr *nla, size_t dstsize)
 {
 	size_t srclen = nla_len(nla);
 	char *src = nla_data(nla);
@@ -749,7 +749,7 @@ ssize_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize)
 
 	return ret;
 }
-EXPORT_SYMBOL(nla_strlcpy);
+EXPORT_SYMBOL(nla_strscpy);
 
 /**
  * nla_strdup - Copy string attribute payload into a newly allocated buffer
diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c
index 7bcfb16854cb..cd80ffed6d26 100644
--- a/net/core/fib_rules.c
+++ b/net/core/fib_rules.c
@@ -563,7 +563,7 @@ static int fib_nl2rule(struct sk_buff *skb, struct nlmsghdr *nlh,
 		struct net_device *dev;
 
 		nlrule->iifindex = -1;
-		nla_strlcpy(nlrule->iifname, tb[FRA_IIFNAME], IFNAMSIZ);
+		nla_strscpy(nlrule->iifname, tb[FRA_IIFNAME], IFNAMSIZ);
 		dev = __dev_get_by_name(net, nlrule->iifname);
 		if (dev)
 			nlrule->iifindex = dev->ifindex;
@@ -573,7 +573,7 @@ static int fib_nl2rule(struct sk_buff *skb, struct nlmsghdr *nlh,
 		struct net_device *dev;
 
 		nlrule->oifindex = -1;
-		nla_strlcpy(nlrule->oifname, tb[FRA_OIFNAME], IFNAMSIZ);
+		nla_strscpy(nlrule->oifname, tb[FRA_OIFNAME], IFNAMSIZ);
 		dev = __dev_get_by_name(net, nlrule->oifname);
 		if (dev)
 			nlrule->oifindex = dev->ifindex;
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 7d7223691783..60917ff4a00b 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1939,7 +1939,7 @@ static const struct rtnl_link_ops *linkinfo_to_kind_ops(const struct nlattr *nla
 	if (linfo[IFLA_INFO_KIND]) {
 		char kind[MODULE_NAME_LEN];
 
-		nla_strlcpy(kind, linfo[IFLA_INFO_KIND], sizeof(kind));
+		nla_strscpy(kind, linfo[IFLA_INFO_KIND], sizeof(kind));
 		ops = rtnl_link_ops_get(kind);
 	}
 
@@ -2953,9 +2953,9 @@ static struct net_device *rtnl_dev_get(struct net *net,
 	if (!ifname) {
 		ifname = buffer;
 		if (ifname_attr)
-			nla_strlcpy(ifname, ifname_attr, IFNAMSIZ);
+			nla_strscpy(ifname, ifname_attr, IFNAMSIZ);
 		else if (altifname_attr)
-			nla_strlcpy(ifname, altifname_attr, ALTIFNAMSIZ);
+			nla_strscpy(ifname, altifname_attr, ALTIFNAMSIZ);
 		else
 			return NULL;
 	}
@@ -2983,7 +2983,7 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 		goto errout;
 
 	if (tb[IFLA_IFNAME])
-		nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
+		nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
 	else
 		ifname[0] = '\0';
 
@@ -3264,7 +3264,7 @@ replay:
 		return err;
 
 	if (tb[IFLA_IFNAME])
-		nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
+		nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
 	else
 		ifname[0] = '\0';
 
@@ -3296,7 +3296,7 @@ replay:
 		memset(linkinfo, 0, sizeof(linkinfo));
 
 	if (linkinfo[IFLA_INFO_KIND]) {
-		nla_strlcpy(kind, linkinfo[IFLA_INFO_KIND], sizeof(kind));
+		nla_strscpy(kind, linkinfo[IFLA_INFO_KIND], sizeof(kind));
 		ops = rtnl_link_ops_get(kind);
 	} else {
 		kind[0] = '\0';
diff --git a/net/decnet/dn_dev.c b/net/decnet/dn_dev.c
index 15d42353f1a3..d1c50a48614b 100644
--- a/net/decnet/dn_dev.c
+++ b/net/decnet/dn_dev.c
@@ -658,7 +658,7 @@ static int dn_nl_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
 	ifa->ifa_dev = dn_db;
 
 	if (tb[IFA_LABEL])
-		nla_strlcpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ);
+		nla_strscpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ);
 	else
 		memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
 
diff --git a/net/ieee802154/nl-mac.c b/net/ieee802154/nl-mac.c
index 6d091e419d3e..9c640d670ffe 100644
--- a/net/ieee802154/nl-mac.c
+++ b/net/ieee802154/nl-mac.c
@@ -149,7 +149,7 @@ static struct net_device *ieee802154_nl_get_dev(struct genl_info *info)
 	if (info->attrs[IEEE802154_ATTR_DEV_NAME]) {
 		char name[IFNAMSIZ + 1];
 
-		nla_strlcpy(name, info->attrs[IEEE802154_ATTR_DEV_NAME],
+		nla_strscpy(name, info->attrs[IEEE802154_ATTR_DEV_NAME],
 			    sizeof(name));
 		dev = dev_get_by_name(&init_net, name);
 	} else if (info->attrs[IEEE802154_ATTR_DEV_INDEX]) {
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index 43e04382c593..75f67994fc85 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -880,7 +880,7 @@ static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh,
 		ifa->ifa_broadcast = nla_get_in_addr(tb[IFA_BROADCAST]);
 
 	if (tb[IFA_LABEL])
-		nla_strlcpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ);
+		nla_strscpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ);
 	else
 		memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
 
diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index 7612ff6111a7..b5400cec4f69 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -973,7 +973,7 @@ bool fib_metrics_match(struct fib_config *cfg, struct fib_info *fi)
 			char tmp[TCP_CA_NAME_MAX];
 			bool ecn_ca = false;
 
-			nla_strlcpy(tmp, nla, sizeof(tmp));
+			nla_strscpy(tmp, nla, sizeof(tmp));
 			val = tcp_ca_get_key_by_name(fi->fib_net, tmp, &ecn_ca);
 		} else {
 			if (nla_len(nla) != sizeof(u32))
diff --git a/net/ipv4/metrics.c b/net/ipv4/metrics.c
index 3205d5f7c8c9..25ea6ac44db9 100644
--- a/net/ipv4/metrics.c
+++ b/net/ipv4/metrics.c
@@ -31,7 +31,7 @@ static int ip_metrics_convert(struct net *net, struct nlattr *fc_mx,
 		if (type == RTAX_CC_ALGO) {
 			char tmp[TCP_CA_NAME_MAX];
 
-			nla_strlcpy(tmp, nla, sizeof(tmp));
+			nla_strscpy(tmp, nla, sizeof(tmp));
 			val = tcp_ca_get_key_by_name(net, tmp, &ecn_ca);
 			if (val == TCP_CA_UNSPEC) {
 				NL_SET_ERR_MSG(extack, "Unknown tcp congestion algorithm");
diff --git a/net/netfilter/ipset/ip_set_hash_netiface.c b/net/netfilter/ipset/ip_set_hash_netiface.c
index 3d74169b794c..ddd51c2e1cb3 100644
--- a/net/netfilter/ipset/ip_set_hash_netiface.c
+++ b/net/netfilter/ipset/ip_set_hash_netiface.c
@@ -226,7 +226,7 @@ hash_netiface4_uadt(struct ip_set *set, struct nlattr *tb[],
 		if (e.cidr > HOST_MASK)
 			return -IPSET_ERR_INVALID_CIDR;
 	}
-	nla_strlcpy(e.iface, tb[IPSET_ATTR_IFACE], IFNAMSIZ);
+	nla_strscpy(e.iface, tb[IPSET_ATTR_IFACE], IFNAMSIZ);
 
 	if (tb[IPSET_ATTR_CADT_FLAGS]) {
 		u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
@@ -443,7 +443,7 @@ hash_netiface6_uadt(struct ip_set *set, struct nlattr *tb[],
 
 	ip6_netmask(&e.ip, e.cidr);
 
-	nla_strlcpy(e.iface, tb[IPSET_ATTR_IFACE], IFNAMSIZ);
+	nla_strscpy(e.iface, tb[IPSET_ATTR_IFACE], IFNAMSIZ);
 
 	if (tb[IPSET_ATTR_CADT_FLAGS]) {
 		u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index bd0e12bf5770..65aa98fc5eb6 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -1282,7 +1282,7 @@ static struct nft_chain *nft_chain_lookup(struct net *net,
 	if (nla == NULL)
 		return ERR_PTR(-EINVAL);
 
-	nla_strlcpy(search, nla, sizeof(search));
+	nla_strscpy(search, nla, sizeof(search));
 
 	WARN_ON(!rcu_read_lock_held() &&
 		!lockdep_commit_lock_is_held(net));
@@ -1722,7 +1722,7 @@ static struct nft_hook *nft_netdev_hook_alloc(struct net *net,
 		goto err_hook_alloc;
 	}
 
-	nla_strlcpy(ifname, attr, IFNAMSIZ);
+	nla_strscpy(ifname, attr, IFNAMSIZ);
 	dev = __dev_get_by_name(net, ifname);
 	if (!dev) {
 		err = -ENOENT;
@@ -5735,7 +5735,7 @@ struct nft_object *nft_obj_lookup(const struct net *net,
 	struct rhlist_head *tmp, *list;
 	struct nft_object *obj;
 
-	nla_strlcpy(search, nla, sizeof(search));
+	nla_strscpy(search, nla, sizeof(search));
 	k.name = search;
 
 	WARN_ON_ONCE(!rcu_read_lock_held() &&
diff --git a/net/netfilter/nfnetlink_acct.c b/net/netfilter/nfnetlink_acct.c
index 5bfec829c12f..5e511df8d709 100644
--- a/net/netfilter/nfnetlink_acct.c
+++ b/net/netfilter/nfnetlink_acct.c
@@ -112,7 +112,7 @@ static int nfnl_acct_new(struct net *net, struct sock *nfnl,
 		nfacct->flags = flags;
 	}
 
-	nla_strlcpy(nfacct->name, tb[NFACCT_NAME], NFACCT_NAME_MAX);
+	nla_strscpy(nfacct->name, tb[NFACCT_NAME], NFACCT_NAME_MAX);
 
 	if (tb[NFACCT_BYTES]) {
 		atomic64_set(&nfacct->bytes,
diff --git a/net/netfilter/nfnetlink_cthelper.c b/net/netfilter/nfnetlink_cthelper.c
index 5b0d0a77379c..0f94fce1d3ed 100644
--- a/net/netfilter/nfnetlink_cthelper.c
+++ b/net/netfilter/nfnetlink_cthelper.c
@@ -146,7 +146,7 @@ nfnl_cthelper_expect_policy(struct nf_conntrack_expect_policy *expect_policy,
 	    !tb[NFCTH_POLICY_EXPECT_TIMEOUT])
 		return -EINVAL;
 
-	nla_strlcpy(expect_policy->name,
+	nla_strscpy(expect_policy->name,
 		    tb[NFCTH_POLICY_NAME], NF_CT_HELPER_NAME_LEN);
 	expect_policy->max_expected =
 		ntohl(nla_get_be32(tb[NFCTH_POLICY_EXPECT_MAX]));
@@ -233,7 +233,7 @@ nfnl_cthelper_create(const struct nlattr * const tb[],
 	if (ret < 0)
 		goto err1;
 
-	nla_strlcpy(helper->name,
+	nla_strscpy(helper->name,
 		    tb[NFCTH_NAME], NF_CT_HELPER_NAME_LEN);
 	size = ntohl(nla_get_be32(tb[NFCTH_PRIV_DATA_LEN]));
 	if (size > sizeof_field(struct nf_conn_help, data)) {
diff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c
index 322bd674963e..a8c4d442231c 100644
--- a/net/netfilter/nft_ct.c
+++ b/net/netfilter/nft_ct.c
@@ -990,7 +990,7 @@ static int nft_ct_helper_obj_init(const struct nft_ctx *ctx,
 	if (!priv->l4proto)
 		return -ENOENT;
 
-	nla_strlcpy(name, tb[NFTA_CT_HELPER_NAME], sizeof(name));
+	nla_strscpy(name, tb[NFTA_CT_HELPER_NAME], sizeof(name));
 
 	if (tb[NFTA_CT_HELPER_L3PROTO])
 		family = ntohs(nla_get_be16(tb[NFTA_CT_HELPER_L3PROTO]));
diff --git a/net/netfilter/nft_log.c b/net/netfilter/nft_log.c
index 57899454a530..a06a46b039c5 100644
--- a/net/netfilter/nft_log.c
+++ b/net/netfilter/nft_log.c
@@ -152,7 +152,7 @@ static int nft_log_init(const struct nft_ctx *ctx,
 		priv->prefix = kmalloc(nla_len(nla) + 1, GFP_KERNEL);
 		if (priv->prefix == NULL)
 			return -ENOMEM;
-		nla_strlcpy(priv->prefix, nla, nla_len(nla) + 1);
+		nla_strscpy(priv->prefix, nla, nla_len(nla) + 1);
 	} else {
 		priv->prefix = (char *)nft_log_null_prefix;
 	}
diff --git a/net/netlabel/netlabel_mgmt.c b/net/netlabel/netlabel_mgmt.c
index eb1d66d20afb..df1b41ed73fd 100644
--- a/net/netlabel/netlabel_mgmt.c
+++ b/net/netlabel/netlabel_mgmt.c
@@ -95,7 +95,7 @@ static int netlbl_mgmt_add_common(struct genl_info *info,
 			ret_val = -ENOMEM;
 			goto add_free_entry;
 		}
-		nla_strlcpy(entry->domain,
+		nla_strscpy(entry->domain,
 			    info->attrs[NLBL_MGMT_A_DOMAIN], tmp_size);
 	}
 
diff --git a/net/nfc/netlink.c b/net/nfc/netlink.c
index 8709f3d4e7c4..573b38ad2f8e 100644
--- a/net/nfc/netlink.c
+++ b/net/nfc/netlink.c
@@ -1226,7 +1226,7 @@ static int nfc_genl_fw_download(struct sk_buff *skb, struct genl_info *info)
 	if (!dev)
 		return -ENODEV;
 
-	nla_strlcpy(firmware_name, info->attrs[NFC_ATTR_FIRMWARE_NAME],
+	nla_strscpy(firmware_name, info->attrs[NFC_ATTR_FIRMWARE_NAME],
 		    sizeof(firmware_name));
 
 	rc = nfc_fw_download(dev, firmware_name);
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index fe540a89b16c..fc23f46a315c 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -939,7 +939,7 @@ struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
 			NL_SET_ERR_MSG(extack, "TC action kind must be specified");
 			goto err_out;
 		}
-		if (nla_strlcpy(act_name, kind, IFNAMSIZ) < 0) {
+		if (nla_strscpy(act_name, kind, IFNAMSIZ) < 0) {
 			NL_SET_ERR_MSG(extack, "TC action name too long");
 			goto err_out;
 		}
diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c
index 8dc3bec0d325..ac7297f42355 100644
--- a/net/sched/act_ipt.c
+++ b/net/sched/act_ipt.c
@@ -166,7 +166,7 @@ static int __tcf_ipt_init(struct net *net, unsigned int id, struct nlattr *nla,
 	if (unlikely(!tname))
 		goto err1;
 	if (tb[TCA_IPT_TABLE] == NULL ||
-	    nla_strlcpy(tname, tb[TCA_IPT_TABLE], IFNAMSIZ) >= IFNAMSIZ)
+	    nla_strscpy(tname, tb[TCA_IPT_TABLE], IFNAMSIZ) >= IFNAMSIZ)
 		strcpy(tname, "mangle");
 
 	t = kmemdup(td, td->u.target_size, GFP_KERNEL);
diff --git a/net/sched/act_simple.c b/net/sched/act_simple.c
index a4f3d0f0daa9..726cc956d06f 100644
--- a/net/sched/act_simple.c
+++ b/net/sched/act_simple.c
@@ -52,7 +52,7 @@ static int alloc_defdata(struct tcf_defact *d, const struct nlattr *defdata)
 	d->tcfd_defdata = kzalloc(SIMP_MAX_DATA, GFP_KERNEL);
 	if (unlikely(!d->tcfd_defdata))
 		return -ENOMEM;
-	nla_strlcpy(d->tcfd_defdata, defdata, SIMP_MAX_DATA);
+	nla_strscpy(d->tcfd_defdata, defdata, SIMP_MAX_DATA);
 	return 0;
 }
 
@@ -71,7 +71,7 @@ static int reset_policy(struct tc_action *a, const struct nlattr *defdata,
 	spin_lock_bh(&d->tcf_lock);
 	goto_ch = tcf_action_set_ctrlact(a, p->action, goto_ch);
 	memset(d->tcfd_defdata, 0, SIMP_MAX_DATA);
-	nla_strlcpy(d->tcfd_defdata, defdata, SIMP_MAX_DATA);
+	nla_strscpy(d->tcfd_defdata, defdata, SIMP_MAX_DATA);
 	spin_unlock_bh(&d->tcf_lock);
 	if (goto_ch)
 		tcf_chain_put_by_act(goto_ch);
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index c2e9661e20d3..ff3e943febaa 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -223,7 +223,7 @@ static inline u32 tcf_auto_prio(struct tcf_proto *tp)
 static bool tcf_proto_check_kind(struct nlattr *kind, char *name)
 {
 	if (kind)
-		return nla_strlcpy(name, kind, IFNAMSIZ) < 0;
+		return nla_strscpy(name, kind, IFNAMSIZ) < 0;
 	memset(name, 0, IFNAMSIZ);
 	return false;
 }
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index 05449286d889..1a2d2471b078 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -1170,7 +1170,7 @@ static struct Qdisc *qdisc_create(struct net_device *dev,
 #ifdef CONFIG_MODULES
 	if (ops == NULL && kind != NULL) {
 		char name[IFNAMSIZ];
-		if (nla_strlcpy(name, kind, IFNAMSIZ) >= 0) {
+		if (nla_strscpy(name, kind, IFNAMSIZ) >= 0) {
 			/* We dropped the RTNL semaphore in order to
 			 * perform the module load.  So, even if we
 			 * succeeded in loading the module we have to
diff --git a/net/tipc/netlink_compat.c b/net/tipc/netlink_compat.c
index 5c6206c9d6a8..82f154989418 100644
--- a/net/tipc/netlink_compat.c
+++ b/net/tipc/netlink_compat.c
@@ -696,7 +696,7 @@ static int tipc_nl_compat_link_dump(struct tipc_nl_compat_msg *msg,
 
 	link_info.dest = nla_get_flag(link[TIPC_NLA_LINK_DEST]);
 	link_info.up = htonl(nla_get_flag(link[TIPC_NLA_LINK_UP]));
-	nla_strlcpy(link_info.str, link[TIPC_NLA_LINK_NAME],
+	nla_strscpy(link_info.str, link[TIPC_NLA_LINK_NAME],
 		    TIPC_MAX_LINK_NAME);
 
 	return tipc_add_tlv(msg->rep, TIPC_TLV_LINK_INFO,
-- 
cgit v1.2.3


From fa69ee5aa48b5b52e8028c2eb486906e9998d081 Mon Sep 17 00:00:00 2001
From: Marco Elver <elver@google.com>
Date: Wed, 25 Nov 2020 23:48:40 +0100
Subject: net: switch to storing KCOV handle directly in sk_buff

It turns out that usage of skb extensions can cause memory leaks. Ido
Schimmel reported: "[...] there are instances that blindly overwrite
'skb->extensions' by invoking skb_copy_header() after __alloc_skb()."

Therefore, give up on using skb extensions for KCOV handle, and instead
directly store kcov_handle in sk_buff.

Fixes: 6370cc3bbd8a ("net: add kcov handle to skb extensions")
Fixes: 85ce50d337d1 ("net: kcov: don't select SKB_EXTENSIONS when there is no NET")
Fixes: 97f53a08cba1 ("net: linux/skbuff.h: combine SKB_EXTENSIONS + KCOV handling")
Link: https://lore.kernel.org/linux-wireless/20201121160941.GA485907@shredder.lan/
Reported-by: Ido Schimmel <idosch@idosch.org>
Signed-off-by: Marco Elver <elver@google.com>
Link: https://lore.kernel.org/r/20201125224840.2014773-1-elver@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 include/linux/skbuff.h | 37 +++++++++++++------------------------
 lib/Kconfig.debug      |  1 -
 net/core/skbuff.c      |  6 ------
 3 files changed, 13 insertions(+), 31 deletions(-)

(limited to 'lib')

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 0a1239819fd2..333bcdc39635 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -701,6 +701,7 @@ typedef unsigned char *sk_buff_data_t;
  *	@transport_header: Transport layer header
  *	@network_header: Network layer header
  *	@mac_header: Link layer header
+ *	@kcov_handle: KCOV remote handle for remote coverage collection
  *	@tail: Tail pointer
  *	@end: End pointer
  *	@head: Head of buffer
@@ -904,6 +905,10 @@ struct sk_buff {
 	__u16			network_header;
 	__u16			mac_header;
 
+#ifdef CONFIG_KCOV
+	u64			kcov_handle;
+#endif
+
 	/* private: */
 	__u32			headers_end[0];
 	/* public: */
@@ -4150,9 +4155,6 @@ enum skb_ext_id {
 #endif
 #if IS_ENABLED(CONFIG_MPTCP)
 	SKB_EXT_MPTCP,
-#endif
-#if IS_ENABLED(CONFIG_KCOV)
-	SKB_EXT_KCOV_HANDLE,
 #endif
 	SKB_EXT_NUM, /* must be last */
 };
@@ -4608,35 +4610,22 @@ static inline void skb_reset_redirect(struct sk_buff *skb)
 #endif
 }
 
-#if IS_ENABLED(CONFIG_KCOV) && IS_ENABLED(CONFIG_SKB_EXTENSIONS)
 static inline void skb_set_kcov_handle(struct sk_buff *skb,
 				       const u64 kcov_handle)
 {
-	/* Do not allocate skb extensions only to set kcov_handle to zero
-	 * (as it is zero by default). However, if the extensions are
-	 * already allocated, update kcov_handle anyway since
-	 * skb_set_kcov_handle can be called to zero a previously set
-	 * value.
-	 */
-	if (skb_has_extensions(skb) || kcov_handle) {
-		u64 *kcov_handle_ptr = skb_ext_add(skb, SKB_EXT_KCOV_HANDLE);
-
-		if (kcov_handle_ptr)
-			*kcov_handle_ptr = kcov_handle;
-	}
+#ifdef CONFIG_KCOV
+	skb->kcov_handle = kcov_handle;
+#endif
 }
 
 static inline u64 skb_get_kcov_handle(struct sk_buff *skb)
 {
-	u64 *kcov_handle = skb_ext_find(skb, SKB_EXT_KCOV_HANDLE);
-
-	return kcov_handle ? *kcov_handle : 0;
-}
+#ifdef CONFIG_KCOV
+	return skb->kcov_handle;
 #else
-static inline void skb_set_kcov_handle(struct sk_buff *skb,
-				       const u64 kcov_handle) { }
-static inline u64 skb_get_kcov_handle(struct sk_buff *skb) { return 0; }
-#endif /* CONFIG_KCOV && CONFIG_SKB_EXTENSIONS */
+	return 0;
+#endif
+}
 
 #endif	/* __KERNEL__ */
 #endif	/* _LINUX_SKBUFF_H */
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 826a205ffd1c..1d15cdaf1b89 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1879,7 +1879,6 @@ config KCOV
 	depends on CC_HAS_SANCOV_TRACE_PC || GCC_PLUGINS
 	select DEBUG_FS
 	select GCC_PLUGIN_SANCOV if !CC_HAS_SANCOV_TRACE_PC
-	select SKB_EXTENSIONS if NET
 	help
 	  KCOV exposes kernel code coverage information in a form suitable
 	  for coverage-guided fuzzing (randomized testing).
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index ad98265f1dd1..90d3423e6017 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -4210,9 +4210,6 @@ static const u8 skb_ext_type_len[] = {
 #if IS_ENABLED(CONFIG_MPTCP)
 	[SKB_EXT_MPTCP] = SKB_EXT_CHUNKSIZEOF(struct mptcp_ext),
 #endif
-#if IS_ENABLED(CONFIG_KCOV)
-	[SKB_EXT_KCOV_HANDLE] = SKB_EXT_CHUNKSIZEOF(u64),
-#endif
 };
 
 static __always_inline unsigned int skb_ext_total_length(void)
@@ -4229,9 +4226,6 @@ static __always_inline unsigned int skb_ext_total_length(void)
 #endif
 #if IS_ENABLED(CONFIG_MPTCP)
 		skb_ext_type_len[SKB_EXT_MPTCP] +
-#endif
-#if IS_ENABLED(CONFIG_KCOV)
-		skb_ext_type_len[SKB_EXT_KCOV_HANDLE] +
 #endif
 		0;
 }
-- 
cgit v1.2.3