diff mbox series

[bpf-next,v6,13/18] net: make vlan_get_tag() return -ENODATA instead of -EINVAL

Message ID 20231012170524.21085-14-larysa.zaremba@intel.com (mailing list archive)
State Changes Requested
Delegated to: BPF
Headers show
Series XDP metadata via kfuncs for ice + VLAN hint | expand

Checks

Context Check Description
bpf/vmtest-bpf-next-PR success PR summary
netdev/series_format fail Series longer than 15 patches (and no cover letter)
netdev/tree_selection success Clearly marked for bpf-next
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: 3836 this patch: 3836
netdev/cc_maintainers warning 3 maintainers not CCed: davem@davemloft.net pabeni@redhat.com edumazet@google.com
netdev/build_clang success Errors and warnings before: 1527 this patch: 1527
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: 4065 this patch: 4065
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 16 lines checked
netdev/kdoc success Errors and warnings before: 2 this patch: 2
netdev/source_inline success Was 0 now: 0
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Commit Message

Larysa Zaremba Oct. 12, 2023, 5:05 p.m. UTC 
__vlan_hwaccel_get_tag() is used in veth XDP hints implementation,
its return value (-EINVAL if skb is not VLAN tagged) is passed to bpf code,
but XDP hints specification requires drivers to return -ENODATA, if a hint
cannot be provided for a particular packet.

Solve this inconsistency by changing error return value of
__vlan_hwaccel_get_tag() from -EINVAL to -ENODATA, do the same thing to
__vlan_get_tag(), because this function is supposed to follow the same
convention. This, in turn, makes -ENODATA the only non-zero value
vlan_get_tag() can return. We can do this with no side effects, because
none of the users of the 3 above-mentioned functions rely on the exact
value.

Suggested-by: Jesper Dangaard Brouer <jbrouer@redhat.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
---
 include/linux/if_vlan.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h
index 3028af87716e..c1645c86eed9 100644
--- a/include/linux/if_vlan.h
+++ b/include/linux/if_vlan.h
@@ -540,7 +540,7 @@  static inline int __vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
 	struct vlan_ethhdr *veth = skb_vlan_eth_hdr(skb);
 
 	if (!eth_type_vlan(veth->h_vlan_proto))
-		return -EINVAL;
+		return -ENODATA;
 
 	*vlan_tci = ntohs(veth->h_vlan_TCI);
 	return 0;
@@ -561,7 +561,7 @@  static inline int __vlan_hwaccel_get_tag(const struct sk_buff *skb,
 		return 0;
 	} else {
 		*vlan_tci = 0;
-		return -EINVAL;
+		return -ENODATA;
 	}
 }