This is a note to let you know that I've just added the patch titled
net/mlx5: HWS, change error flow on matcher disconnect
to the 6.13-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-mlx5-hws-change-error-flow-on-matcher-disconnect.patch
and it can be found in the queue-6.13 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit a8a1b78f5ba01a25479c9f5c11f02b73d70c5d39
Author: Yevgeny Kliteynik <kliteyn@xxxxxxxxxx>
Date: Thu Jan 2 20:14:05 2025 +0200
net/mlx5: HWS, change error flow on matcher disconnect
[ Upstream commit 1ce840c7a659aa53a31ef49f0271b4fd0dc10296 ]
Currently, when firmware failure occurs during matcher disconnect flow,
the error flow of the function reconnects the matcher back and returns
an error, which continues running the calling function and eventually
frees the matcher that is being disconnected.
This leads to a case where we have a freed matcher on the matchers list,
which in turn leads to use-after-free and eventual crash.
This patch fixes that by not trying to reconnect the matcher back when
some FW command fails during disconnect.
Note that we're dealing here with FW error. We can't overcome this
problem. This might lead to bad steering state (e.g. wrong connection
between matchers), and will also lead to resource leakage, as it is
the case with any other error handling during resource destruction.
However, the goal here is to allow the driver to continue and not crash
the machine with use-after-free error.
Signed-off-by: Yevgeny Kliteynik <kliteyn@xxxxxxxxxx>
Signed-off-by: Itamar Gozlan <igozlan@xxxxxxxxxx>
Reviewed-by: Mark Bloch <mbloch@xxxxxxxxxx>
Signed-off-by: Tariq Toukan <tariqt@xxxxxxxxxx>
Link: https://patch.msgid.link/20250102181415.1477316-7-tariqt@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/steering/hws/matcher.c b/drivers/net/ethernet/mellanox/mlx5/core/steering/hws/matcher.c
index 1bb3a6f8c3cda..e94f96c0c781f 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/steering/hws/matcher.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/steering/hws/matcher.c
@@ -165,14 +165,14 @@ static int hws_matcher_disconnect(struct mlx5hws_matcher *matcher)
next->match_ste.rtc_0_id,
next->match_ste.rtc_1_id);
if (ret) {
- mlx5hws_err(tbl->ctx, "Failed to disconnect matcher\n");
- goto matcher_reconnect;
+ mlx5hws_err(tbl->ctx, "Fatal error, failed to disconnect matcher\n");
+ return ret;
}
} else {
ret = mlx5hws_table_connect_to_miss_table(tbl, tbl->default_miss.miss_tbl);
if (ret) {
- mlx5hws_err(tbl->ctx, "Failed to disconnect last matcher\n");
- goto matcher_reconnect;
+ mlx5hws_err(tbl->ctx, "Fatal error, failed to disconnect last matcher\n");
+ return ret;
}
}
@@ -180,27 +180,19 @@ static int hws_matcher_disconnect(struct mlx5hws_matcher *matcher)
if (prev_ft_id == tbl->ft_id) {
ret = mlx5hws_table_update_connected_miss_tables(tbl);
if (ret) {
- mlx5hws_err(tbl->ctx, "Fatal error, failed to update connected miss table\n");
- goto matcher_reconnect;
+ mlx5hws_err(tbl->ctx,
+ "Fatal error, failed to update connected miss table\n");
+ return ret;
}
}
ret = mlx5hws_table_ft_set_default_next_ft(tbl, prev_ft_id);
if (ret) {
mlx5hws_err(tbl->ctx, "Fatal error, failed to restore matcher ft default miss\n");
- goto matcher_reconnect;
+ return ret;
}
return 0;
-
-matcher_reconnect:
- if (list_empty(&tbl->matchers_list) || !prev)
- list_add(&matcher->list_node, &tbl->matchers_list);
- else
- /* insert after prev matcher */
- list_add(&matcher->list_node, &prev->list_node);
-
- return ret;
}
static void hws_matcher_set_rtc_attr_sz(struct mlx5hws_matcher *matcher,
