diff mbox series

[net-next,7/7] net: add debug check in skb_reset_mac_header()

Message ID 20241105174403.850330-8-edumazet@google.com (mailing list archive)
State New
Delegated to: Netdev Maintainers
Headers show
Series net: add debug checks to skb_reset_xxx_header() | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 42 this patch: 42
netdev/build_tools success Errors and warnings before: 2 (+0) this patch: 2 (+0)
netdev/cc_maintainers warning 1 maintainers not CCed: horms@kernel.org
netdev/build_clang success Errors and warnings before: 78 this patch: 78
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
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: 5008 this patch: 5008
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 11 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 58 this patch: 58
netdev/source_inline success Was 0 now: 0
netdev/contest pending net-next-2024-11-06--00-00 (tests: 0)

Commit Message

Eric Dumazet Nov. 5, 2024, 5:44 p.m. UTC 
Make sure (skb->data - skb->head) can fit in skb->mac_header

This needs CONFIG_DEBUG_NET=y.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 include/linux/skbuff.h | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

Comments

Joe Damato Nov. 5, 2024, 5:59 p.m. UTC | #1 
On Tue, Nov 05, 2024 at 05:44:03PM +0000, Eric Dumazet wrote:
> Make sure (skb->data - skb->head) can fit in skb->mac_header
> 
> This needs CONFIG_DEBUG_NET=y.
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> ---
>  include/linux/skbuff.h | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)

Reviewed-by: Joe Damato <jdamato@fastly.com>
diff mbox series

Patch

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index f1e49a32880df8f3716c585d13c1085a2183978a..e5095d75abba18c5c5301ddc39c40cdcf5e528ed 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -3063,7 +3063,10 @@  static inline void skb_unset_mac_header(struct sk_buff *skb)
 
 static inline void skb_reset_mac_header(struct sk_buff *skb)
 {
-	skb->mac_header = skb->data - skb->head;
+	long offset = skb->data - skb->head;
+
+	DEBUG_NET_WARN_ON_ONCE(offset != (typeof(skb->mac_header))offset);
+	skb->mac_header = offset;
 }
 
 static inline void skb_set_mac_header(struct sk_buff *skb, const int offset)