diff options
| author | Vladimir Oltean <vladimir.oltean@nxp.com> | 2026-01-21 00:10:39 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-01-30 12:28:43 +0300 |
| commit | ac42e52979fbf052b79c94e59916dd4caf9cb555 (patch) | |
| tree | b5c95f9f43236f0761f72793c3b8a51aff9892a0 | |
| parent | bc3c8d2493c6f4d2038844dc8b7ee93de050f7fa (diff) | |
| download | linux-ac42e52979fbf052b79c94e59916dd4caf9cb555.tar.xz | |
net: dsa: fix off-by-one in maximum bridge ID determination
[ Upstream commit dfca045cd4d0ea07ff4198ba392be3e718acaddc ]
Prior to the blamed commit, the bridge_num range was from
0 to ds->max_num_bridges - 1. After the commit, it is from
1 to ds->max_num_bridges.
So this check:
if (bridge_num >= max)
return 0;
must be updated to:
if (bridge_num > max)
return 0;
in order to allow the last bridge_num value (==max) to be used.
This is easiest visible when a driver sets ds->max_num_bridges=1.
The observed behaviour is that even the first created bridge triggers
the netlink extack "Range of offloadable bridges exceeded" warning, and
is handled in software rather than being offloaded.
Fixes: 3f9bb0301d50 ("net: dsa: make dp->bridge_num one-based")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://patch.msgid.link/20260120211039.3228999-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | net/dsa/dsa.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c index 97599e0d5a1d..76a086e846c4 100644 --- a/net/dsa/dsa.c +++ b/net/dsa/dsa.c @@ -157,7 +157,7 @@ unsigned int dsa_bridge_num_get(const struct net_device *bridge_dev, int max) bridge_num = find_next_zero_bit(&dsa_fwd_offloading_bridges, DSA_MAX_NUM_OFFLOADING_BRIDGES, 1); - if (bridge_num >= max) + if (bridge_num > max) return 0; set_bit(bridge_num, &dsa_fwd_offloading_bridges); |