[PATCH net-next] net: fix skb_panic to output real address

[PATCH net-next] net: fix skb_panic to output real address

[Jesper Dangaard Brouer]

In skb_panic() the real pointer values are really needed to diagnose
issues, e.g. data and head are related (to calculate headroom). The
hashed versions of the addresses doesn't make much sense here. The
patch use the printk specifier %px to print the actual address.

The printk documentation on %px:
https://www.kernel.org/doc/html/latest/core-api/printk-formats.html#unmodified-addresses

Fixes: ad67b74d2469 ("printk: hash addresses printed with %p")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 net/core/skbuff.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 7e29590482ce..1bf0c3d278e7 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -102,7 +102,7 @@ EXPORT_SYMBOL(sysctl_max_skb_frags);
 static void skb_panic(struct sk_buff *skb, unsigned int sz, void *addr,
 		      const char msg[])
 {
-	pr_emerg("%s: text:%p len:%d put:%d head:%p data:%p tail:%#lx end:%#lx dev:%s\n",
+	pr_emerg("%s: text:%px len:%d put:%d head:%px data:%px tail:%#lx end:%#lx dev:%s\n",
 		 msg, addr, skb->len, sz, skb->head, skb->data,
 		 (unsigned long)skb->tail, (unsigned long)skb->end,
 		 skb->dev ? skb->dev->name : "<NULL>");

Re: [PATCH net-next] net: fix skb_panic to output real address

[David Miller]

From: Jesper Dangaard Brouer <brouer@redhat.com>
Date: Mon, 27 Apr 2020 18:37:43 +0200

> In skb_panic() the real pointer values are really needed to diagnose
> issues, e.g. data and head are related (to calculate headroom). The
> hashed versions of the addresses doesn't make much sense here. The
> patch use the printk specifier %px to print the actual address.
> 
> The printk documentation on %px:
> https://www.kernel.org/doc/html/latest/core-api/printk-formats.html#unmodified-addresses
> 
> Fixes: ad67b74d2469 ("printk: hash addresses printed with %p")
> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>

Applied.