diff mbox series

[net] appletalk: Improve handling of broadcast packets

Message ID 20240505185456.214677-1-doug@schmorgal.com (mailing list archive)
State Accepted
Commit 2e82a58d6c0797092eabe7ba66a532c11548047f
Delegated to: Netdev Maintainers
Headers show
Series [net] appletalk: Improve handling of broadcast packets | 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 fail Series targets non-next tree, but doesn't contain any Fixes tags
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 929 this patch: 929
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 1 maintainers not CCed: lukas.bulwahn@gmail.com
netdev/build_clang success Errors and warnings before: 937 this patch: 937
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: 940 this patch: 940
netdev/checkpatch warning WARNING: line length of 82 exceeds 80 columns WARNING: line length of 90 exceeds 80 columns WARNING: line length of 93 exceeds 80 columns
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 3 this patch: 3
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-05-08--03-00 (tests: 1005)

Commit Message

Doug Brown May 5, 2024, 6:54 p.m. UTC 
From: Vincent Duvert <vincent.ldev@duvert.net>

When a broadcast AppleTalk packet is received, prefer queuing it on the
socket whose address matches the address of the interface that received
the packet (and is listening on the correct port). Userspace
applications that handle such packets will usually send a response on
the same socket that received the packet; this fix allows the response
to be sent on the correct interface.

If a socket matching the interface's address is not found, an arbitrary
socket listening on the correct port will be used, if any. This matches
the implementation's previous behavior.

Fixes atalkd's responses to network information requests when multiple
network interfaces are configured to use AppleTalk.

Link: https://lore.kernel.org/netdev/20200722113752.1218-2-vincent.ldev@duvert.net/
Link: https://gist.github.com/VinDuv/4db433b6dce39d51a5b7847ee749b2a4
Signed-off-by: Vincent Duvert <vincent.ldev@duvert.net>
Signed-off-by: Doug Brown <doug@schmorgal.com>
---
 net/appletalk/ddp.c | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

Comments

patchwork-bot+netdevbpf@kernel.org May 8, 2024, 11:20 a.m. UTC | #1 
Hello:

This patch was applied to netdev/net.git (main)
by David S. Miller <davem@davemloft.net>:

On Sun,  5 May 2024 11:54:57 -0700 you wrote:
> From: Vincent Duvert <vincent.ldev@duvert.net>
> 
> When a broadcast AppleTalk packet is received, prefer queuing it on the
> socket whose address matches the address of the interface that received
> the packet (and is listening on the correct port). Userspace
> applications that handle such packets will usually send a response on
> the same socket that received the packet; this fix allows the response
> to be sent on the correct interface.
> 
> [...]

Here is the summary with links:
  - [net] appletalk: Improve handling of broadcast packets
    https://git.kernel.org/netdev/net/c/2e82a58d6c07

You are awesome, thank you!
diff mbox series

Patch

diff --git a/net/appletalk/ddp.c b/net/appletalk/ddp.c
index 198f5ba2feae..b068651984fe 100644
--- a/net/appletalk/ddp.c
+++ b/net/appletalk/ddp.c
@@ -88,6 +88,7 @@  static inline void atalk_remove_socket(struct sock *sk)
 static struct sock *atalk_search_socket(struct sockaddr_at *to,
 					struct atalk_iface *atif)
 {
+	struct sock *def_socket = NULL;
 	struct sock *s;
 
 	read_lock_bh(&atalk_sockets_lock);
@@ -98,8 +99,20 @@  static struct sock *atalk_search_socket(struct sockaddr_at *to,
 			continue;
 
 		if (to->sat_addr.s_net == ATADDR_ANYNET &&
-		    to->sat_addr.s_node == ATADDR_BCAST)
-			goto found;
+		    to->sat_addr.s_node == ATADDR_BCAST) {
+			if (atif->address.s_node == at->src_node &&
+			    atif->address.s_net == at->src_net) {
+				/* This socket's address matches the address of the interface
+				 * that received the packet -- use it
+				 */
+				goto found;
+			}
+
+			/* Continue searching for a socket matching the interface address,
+			 * but use this socket by default if no other one is found
+			 */
+			def_socket = s;
+		}
 
 		if (to->sat_addr.s_net == at->src_net &&
 		    (to->sat_addr.s_node == at->src_node ||
@@ -116,7 +129,7 @@  static struct sock *atalk_search_socket(struct sockaddr_at *to,
 			goto found;
 		}
 	}
-	s = NULL;
+	s = def_socket;
 found:
 	read_unlock_bh(&atalk_sockets_lock);
 	return s;