2022-09-28 13:01:08

by Richard Gobert

Subject: [PATCH] net-next: skbuff: refactor pskb_pull

pskb_may_pull already contains all of the checks performed by
pskb_pull.
Use pskb_may_pull for validation in pskb_pull, eliminating the
duplication and making __pskb_pull obsolete.
Replace __pskb_pull with pskb_pull where applicable.

Signed-off-by: Richard Gobert <[email protected]>
---
include/linux/skbuff.h | 23 +++++++++--------------
net/ipv6/ip6_offload.c | 2 +-
net/mac80211/rx.c | 4 ++--
net/xfrm/espintcp.c | 2 +-
4 files changed, 13 insertions(+), 18 deletions(-)

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index ca8afa382bf2..615cd660dd69 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -2587,20 +2587,6 @@ void *skb_pull_data(struct sk_buff *skb, size_t len);

void *__pskb_pull_tail(struct sk_buff *skb, int delta);

-static inline void *__pskb_pull(struct sk_buff *skb, unsigned int len)
-{
- if (len > skb_headlen(skb) &&
- !__pskb_pull_tail(skb, len - skb_headlen(skb)))
- return NULL;
- skb->len -= len;
- return skb->data += len;
-}
-
-static inline void *pskb_pull(struct sk_buff *skb, unsigned int len)
-{
- return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len);
-}
-
static inline bool pskb_may_pull(struct sk_buff *skb, unsigned int len)
{
if (likely(len <= skb_headlen(skb)))
@@ -2610,6 +2596,15 @@ static inline bool pskb_may_pull(struct sk_buff *skb, unsigned int len)
return __pskb_pull_tail(skb, len - skb_headlen(skb)) != NULL;
}

+static inline void *pskb_pull(struct sk_buff *skb, unsigned int len)
+{
+ if (!pskb_may_pull(skb, len))
+ return NULL;
+
+ skb->len -= len;
+ return skb->data += len;
+}
+
void skb_condense(struct sk_buff *skb);

/**
diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c
index d12dba2dd535..d31775b87b6a 100644
--- a/net/ipv6/ip6_offload.c
+++ b/net/ipv6/ip6_offload.c
@@ -235,7 +235,7 @@ INDIRECT_CALLABLE_SCOPE struct sk_buff *ipv6_gro_receive(struct list_head *head,
proto = iph->nexthdr;
ops = rcu_dereference(inet6_offloads[proto]);
if (!ops || !ops->callbacks.gro_receive) {
- __pskb_pull(skb, skb_gro_offset(skb));
+ pskb_pull(skb, skb_gro_offset(skb));
skb_gro_frag0_invalidate(skb);
proto = ipv6_gso_pull_exthdrs(skb, proto);
skb_gro_pull(skb, -skb_transport_offset(skb));
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 57df21e2170a..addc8294198b 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -49,7 +49,7 @@ static struct sk_buff *ieee80211_clean_skb(struct sk_buff *skb,

if (present_fcs_len)
__pskb_trim(skb, skb->len - present_fcs_len);
- __pskb_pull(skb, rtap_space);
+ pskb_pull(skb, rtap_space);

hdr = (void *)skb->data;
fc = hdr->frame_control;
@@ -74,7 +74,7 @@ static struct sk_buff *ieee80211_clean_skb(struct sk_buff *skb,

memmove(skb->data + IEEE80211_HT_CTL_LEN, skb->data,
hdrlen - IEEE80211_HT_CTL_LEN);
- __pskb_pull(skb, IEEE80211_HT_CTL_LEN);
+ pskb_pull(skb, IEEE80211_HT_CTL_LEN);

return skb;
}
diff --git a/net/xfrm/espintcp.c b/net/xfrm/espintcp.c
index 82d14eea1b5a..2000d67f9982 100644
--- a/net/xfrm/espintcp.c
+++ b/net/xfrm/espintcp.c
@@ -91,7 +91,7 @@ static void espintcp_rcv(struct strparser *strp, struct sk_buff *skb)
}

/* remove header, leave non-ESP marker/SPI */
- if (!__pskb_pull(skb, rxm->offset + 2)) {
+ if (!pskb_pull(skb, rxm->offset + 2)) {
XFRM_INC_STATS(sock_net(strp->sk), LINUX_MIB_XFRMINERROR);
kfree_skb(skb);
return;
--
2.20.1

2022-09-30 11:53:25

by patchwork-bot+netdevbpf

Subject: Re: [PATCH] net-next: skbuff: refactor pskb_pull

Hello:

This patch was applied to netdev/net-next.git (master)
by David S. Miller <[email protected]>:

On Wed, 28 Sep 2022 14:55:31 +0200 you wrote:
> pskb_may_pull already contains all of the checks performed by
> pskb_pull.
> Use pskb_may_pull for validation in pskb_pull, eliminating the
> duplication and making __pskb_pull obsolete.
> Replace __pskb_pull with pskb_pull where applicable.
>
> Signed-off-by: Richard Gobert <[email protected]>
>
> [...]

Here is the summary with links:
- net-next: skbuff: refactor pskb_pull
https://git.kernel.org/netdev/net-next/c/d427c8999b07

You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html