diff mbox series

[v2,net-next,7/8] net: add debug checks in napi_consume_skb and __napi_alloc_skb()

Message ID 20220608160438.1342569-8-eric.dumazet@gmail.com (mailing list archive)
State Accepted
Commit ee2640df2393141a2975af726802b349d51713be
Delegated to: Netdev Maintainers
Headers show
Series net: few debug refinements | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 2 this patch: 2
netdev/cc_maintainers success CCed 5 of 5 maintainers
netdev/build_clang success Errors and warnings before: 6 this patch: 6
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 2 this patch: 2
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 15 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Eric Dumazet June 8, 2022, 4:04 p.m. UTC 
From: Eric Dumazet <edumazet@google.com>

Commit 6454eca81eae ("net: Use lockdep_assert_in_softirq()
in napi_consume_skb()") added a check in napi_consume_skb()
which is a bit weak.

napi_consume_skb() and __napi_alloc_skb() should only
be used from BH context, not from hard irq or nmi context,
otherwise we could have races.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 net/core/skbuff.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index cf83d9b8f41dc28ae11391f2651e5abee3dcde8f..fec75f8bf1f416f05c14f76009a15412b2559b6e 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -560,6 +560,7 @@  struct sk_buff *__napi_alloc_skb(struct napi_struct *napi, unsigned int len,
 	struct sk_buff *skb;
 	void *data;
 
+	DEBUG_NET_WARN_ON_ONCE(!in_softirq());
 	len += NET_SKB_PAD + NET_IP_ALIGN;
 
 	/* If requested length is either too small or too big,
@@ -981,7 +982,7 @@  void napi_consume_skb(struct sk_buff *skb, int budget)
 		return;
 	}
 
-	lockdep_assert_in_softirq();
+	DEBUG_NET_WARN_ON_ONCE(!in_softirq());
 
 	if (!skb_unref(skb))
 		return;