6.1-stable review patch. If anyone has any objections, please let me know.
------------------
From: Vladimir Oltean <vladimir.oltean@nxp.com>
[ Upstream commit 4f1d06cf8aaa9d2cb18e5ee8835aff6177256bc6 ]
The blamed commit replaced "return ret" statements in b53_fdb_dump()
with "break;" which jumps to the mutex_unlock() -> return 0 section.
This is notably problematic because it swallows errors from the
b53_fdb_copy() -> cb() path, and this will result in FDB dump truncation
when the netlink skb overflows - see commit 21b52fed928e ("net: dsa:
sja1105: fix broken backpressure in .port_fdb_dump").
Let's go back to "return ret". We don't need to preinitialize "ret" with
0, because the "do {} while" block guarantees we cannot reach the end of
the function without at least once calling b53_arl_search_wait(), which
will have initialized ret to some valid value.
Fixes: f7eb4a1c0864 ("net: dsa: b53: serialize access to the ARL table")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://patch.msgid.link/20260812201121.2012356-1-vladimir.oltean@nxp.com (local)
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/dsa/b53/b53_common.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c
index 49fb610db484e..aaf9fbaefd6b9 100644
--- a/drivers/net/dsa/b53/b53_common.c
+++ b/drivers/net/dsa/b53/b53_common.c
@@ -1863,7 +1863,7 @@ int b53_fdb_dump(struct dsa_switch *ds, int port,
mutex_unlock(&priv->arl_mutex);
- return 0;
+ return ret;
}
EXPORT_SYMBOL(b53_fdb_dump);
--
2.53.0