diff mbox series

[net,v2,1/2] netdev-genl: avoid empty messages in napi get

Message ID 20241219032833.1165433-1-kuba@kernel.org (mailing list archive)
State Accepted
Commit 4a25201aa46ce88e8e31f9ccdec0e4e3dd6bb736
Delegated to: Netdev Maintainers
Headers show
Series [net,v2,1/2] netdev-genl: avoid empty messages in napi get | expand

Checks

Context Check Description
netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for net
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 1 maintainers not CCed: horms@kernel.org
netdev/build_clang success Errors and warnings before: 1 this patch: 1
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 Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 13 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-12-19--12-00 (tests: 881)

Commit Message

Jakub Kicinski Dec. 19, 2024, 3:28 a.m. UTC
Empty netlink responses from do() are not correct (as opposed to
dump() where not dumping anything is perfectly fine).
We should return an error if the target object does not exist,
in this case if the netdev is down we "hide" the NAPI instances.

Fixes: 27f91aaf49b3 ("netdev-genl: Add netlink framework functions for napi")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
v2:
 - fix the locking
v1: https://lore.kernel.org/20241218024305.823683-1-kuba@kernel.org

CC: jdamato@fastly.com
CC: almasrymina@google.com
CC: sridhar.samudrala@intel.com
CC: amritha.nambiar@intel.com
---
 net/core/netdev-genl.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

Comments

Eric Dumazet Dec. 19, 2024, 1:28 p.m. UTC | #1
On Thu, Dec 19, 2024 at 4:28 AM Jakub Kicinski <kuba@kernel.org> wrote:
>
> Empty netlink responses from do() are not correct (as opposed to
> dump() where not dumping anything is perfectly fine).
> We should return an error if the target object does not exist,
> in this case if the netdev is down we "hide" the NAPI instances.
>
> Fixes: 27f91aaf49b3 ("netdev-genl: Add netlink framework functions for napi")
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Reviewed-by: Eric Dumazet <edumazet@google.com>
patchwork-bot+netdevbpf@kernel.org Dec. 20, 2024, 9 p.m. UTC | #2
Hello:

This series was applied to netdev/net.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Wed, 18 Dec 2024 19:28:32 -0800 you wrote:
> Empty netlink responses from do() are not correct (as opposed to
> dump() where not dumping anything is perfectly fine).
> We should return an error if the target object does not exist,
> in this case if the netdev is down we "hide" the NAPI instances.
> 
> Fixes: 27f91aaf49b3 ("netdev-genl: Add netlink framework functions for napi")
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> 
> [...]

Here is the summary with links:
  - [net,v2,1/2] netdev-genl: avoid empty messages in napi get
    https://git.kernel.org/netdev/net/c/4a25201aa46c
  - [net,v2,2/2] selftests: drv-net: test empty queue and NAPI responses in netlink
    https://git.kernel.org/netdev/net/c/30b981796b94

You are awesome, thank you!
diff mbox series

Patch

diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c
index 2d3ae0cd3ad2..b0772d135efb 100644
--- a/net/core/netdev-genl.c
+++ b/net/core/netdev-genl.c
@@ -246,8 +246,12 @@  int netdev_nl_napi_get_doit(struct sk_buff *skb, struct genl_info *info)
 	rcu_read_unlock();
 	rtnl_unlock();
 
-	if (err)
+	if (err) {
 		goto err_free_msg;
+	} else if (!rsp->len) {
+		err = -ENOENT;
+		goto err_free_msg;
+	}
 
 	return genlmsg_reply(rsp, info);