Commit fe87922c authored by Arnd Bergmann's avatar Arnd Bergmann Committed by Jakub Kicinski
Browse files

net/mlx5: fix possible stack overflows 



A couple of debug functions use a 512 byte temporary buffer and call another
function that has another buffer of the same size, which in turn exceeds the
usual warning limit for excessive stack usage:

drivers/net/ethernet/mellanox/mlx5/core/steering/dr_dbg.c:1073:1: error: stack frame size (1448) exceeds limit (1024) in 'dr_dump_start' [-Werror,-Wframe-larger-than]
dr_dump_start(struct seq_file *file, loff_t *pos)
drivers/net/ethernet/mellanox/mlx5/core/steering/dr_dbg.c:1009:1: error: stack frame size (1120) exceeds limit (1024) in 'dr_dump_domain' [-Werror,-Wframe-larger-than]
dr_dump_domain(struct seq_file *file, struct mlx5dr_domain *dmn)
drivers/net/ethernet/mellanox/mlx5/core/steering/dr_dbg.c:705:1: error: stack frame size (1104) exceeds limit (1024) in 'dr_dump_matcher_rx_tx' [-Werror,-Wframe-larger-than]
dr_dump_matcher_rx_tx(struct seq_file *file, bool is_rx,

Rework these so that each of the various code paths only ever has one of
these buffers in it, and exactly the functions that declare one have
the 'noinline_for_stack' annotation that prevents them from all being
inlined into the same caller.

Fixes: 917d1e79 ("net/mlx5: DR, Change SWS usage to debug fs seq_file interface")
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Reviewed-by: default avatarJiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/all/20240219100506.648089-1-arnd@kernel.org/


Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Acked-by: default avatarTariq Toukan <tariqt@nvidia.com>
Link: https://lore.kernel.org/r/20240408074142.3007036-1-arnd@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 186abfcd

drivers/net/ethernet/mellanox/mlx5/core/steering/dr_dbg.c

+41 −41
Original line number Diff line number Diff line
@@ -205,12 +205,11 @@ dr_dump_hex_print(char hex[DR_HEX_SIZE], char *src, u32 size) 
}



static int

dr_dump_rule_action_mem(struct seq_file *file, const u64 rule_id,

dr_dump_rule_action_mem(struct seq_file *file, char *buff, const u64 rule_id,

			struct mlx5dr_rule_action_member *action_mem)

{

	struct mlx5dr_action *action = action_mem->action;

	const u64 action_id = DR_DBG_PTR_TO_ID(action);

	char buff[MLX5DR_DEBUG_DUMP_BUFF_LENGTH];

	u64 hit_tbl_ptr, miss_tbl_ptr;

	u32 hit_tbl_id, miss_tbl_id;

	int ret;
@@ -488,10 +487,9 @@ dr_dump_rule_action_mem(struct seq_file *file, const u64 rule_id, 
}



static int

dr_dump_rule_mem(struct seq_file *file, struct mlx5dr_ste *ste,

dr_dump_rule_mem(struct seq_file *file, char *buff, struct mlx5dr_ste *ste,

		 bool is_rx, const u64 rule_id, u8 format_ver)

{

	char buff[MLX5DR_DEBUG_DUMP_BUFF_LENGTH];

	char hw_ste_dump[DR_HEX_SIZE];

	u32 mem_rec_type;

	int ret;
@@ -522,7 +520,8 @@ dr_dump_rule_mem(struct seq_file *file, struct mlx5dr_ste *ste, 
}



static int

dr_dump_rule_rx_tx(struct seq_file *file, struct mlx5dr_rule_rx_tx *rule_rx_tx,

dr_dump_rule_rx_tx(struct seq_file *file, char *buff,

		   struct mlx5dr_rule_rx_tx *rule_rx_tx,

		   bool is_rx, const u64 rule_id, u8 format_ver)

{

	struct mlx5dr_ste *ste_arr[DR_RULE_MAX_STES + DR_ACTION_MAX_STES];
@@ -533,7 +532,7 @@ dr_dump_rule_rx_tx(struct seq_file *file, struct mlx5dr_rule_rx_tx *rule_rx_tx, 
		return 0;



	while (i--) {

		ret = dr_dump_rule_mem(file, ste_arr[i], is_rx, rule_id,

		ret = dr_dump_rule_mem(file, buff, ste_arr[i], is_rx, rule_id,

				       format_ver);

		if (ret < 0)

			return ret;
@@ -542,7 +541,8 @@ dr_dump_rule_rx_tx(struct seq_file *file, struct mlx5dr_rule_rx_tx *rule_rx_tx, 
	return 0;

}



static int dr_dump_rule(struct seq_file *file, struct mlx5dr_rule *rule)

static noinline_for_stack int

dr_dump_rule(struct seq_file *file, struct mlx5dr_rule *rule)

{

	struct mlx5dr_rule_action_member *action_mem;

	const u64 rule_id = DR_DBG_PTR_TO_ID(rule);
@@ -565,19 +565,19 @@ static int dr_dump_rule(struct seq_file *file, struct mlx5dr_rule *rule) 
		return ret;



	if (rx->nic_matcher) {

		ret = dr_dump_rule_rx_tx(file, rx, true, rule_id, format_ver);

		ret = dr_dump_rule_rx_tx(file, buff, rx, true, rule_id, format_ver);

		if (ret < 0)

			return ret;

	}



	if (tx->nic_matcher) {

		ret = dr_dump_rule_rx_tx(file, tx, false, rule_id, format_ver);

		ret = dr_dump_rule_rx_tx(file, buff, tx, false, rule_id, format_ver);

		if (ret < 0)

			return ret;

	}



	list_for_each_entry(action_mem, &rule->rule_actions_list, list) {

		ret = dr_dump_rule_action_mem(file, rule_id, action_mem);

		ret = dr_dump_rule_action_mem(file, buff, rule_id, action_mem);

		if (ret < 0)

			return ret;

	}
@@ -586,10 +586,10 @@ static int dr_dump_rule(struct seq_file *file, struct mlx5dr_rule *rule) 
}



static int

dr_dump_matcher_mask(struct seq_file *file, struct mlx5dr_match_param *mask,

dr_dump_matcher_mask(struct seq_file *file, char *buff,

		     struct mlx5dr_match_param *mask,

		     u8 criteria, const u64 matcher_id)

{

	char buff[MLX5DR_DEBUG_DUMP_BUFF_LENGTH];

	char dump[DR_HEX_SIZE];

	int ret;
@@ -681,10 +681,10 @@ dr_dump_matcher_mask(struct seq_file *file, struct mlx5dr_match_param *mask, 
}



static int

dr_dump_matcher_builder(struct seq_file *file, struct mlx5dr_ste_build *builder,

dr_dump_matcher_builder(struct seq_file *file, char *buff,

			struct mlx5dr_ste_build *builder,

			u32 index, bool is_rx, const u64 matcher_id)

{

	char buff[MLX5DR_DEBUG_DUMP_BUFF_LENGTH];

	int ret;



	ret = snprintf(buff, MLX5DR_DEBUG_DUMP_BUFF_LENGTH,
@@ -702,11 +702,10 @@ dr_dump_matcher_builder(struct seq_file *file, struct mlx5dr_ste_build *builder, 
}



static int

dr_dump_matcher_rx_tx(struct seq_file *file, bool is_rx,

dr_dump_matcher_rx_tx(struct seq_file *file, char *buff, bool is_rx,

		      struct mlx5dr_matcher_rx_tx *matcher_rx_tx,

		      const u64 matcher_id)

{

	char buff[MLX5DR_DEBUG_DUMP_BUFF_LENGTH];

	enum dr_dump_rec_type rec_type;

	u64 s_icm_addr, e_icm_addr;

	int i, ret;
@@ -731,7 +730,7 @@ dr_dump_matcher_rx_tx(struct seq_file *file, bool is_rx, 
		return ret;



	for (i = 0; i < matcher_rx_tx->num_of_builders; i++) {

		ret = dr_dump_matcher_builder(file,

		ret = dr_dump_matcher_builder(file, buff,

					      &matcher_rx_tx->ste_builder[i],

					      i, is_rx, matcher_id);

		if (ret < 0)
@@ -741,7 +740,7 @@ dr_dump_matcher_rx_tx(struct seq_file *file, bool is_rx, 
	return 0;

}



static int

static noinline_for_stack int

dr_dump_matcher(struct seq_file *file, struct mlx5dr_matcher *matcher)

{

	struct mlx5dr_matcher_rx_tx *rx = &matcher->rx;
@@ -763,19 +762,19 @@ dr_dump_matcher(struct seq_file *file, struct mlx5dr_matcher *matcher) 
	if (ret)

		return ret;



	ret = dr_dump_matcher_mask(file, &matcher->mask,

	ret = dr_dump_matcher_mask(file, buff, &matcher->mask,

				   matcher->match_criteria, matcher_id);

	if (ret < 0)

		return ret;



	if (rx->nic_tbl) {

		ret = dr_dump_matcher_rx_tx(file, true, rx, matcher_id);

		ret = dr_dump_matcher_rx_tx(file, buff, true, rx, matcher_id);

		if (ret < 0)

			return ret;

	}



	if (tx->nic_tbl) {

		ret = dr_dump_matcher_rx_tx(file, false, tx, matcher_id);

		ret = dr_dump_matcher_rx_tx(file, buff, false, tx, matcher_id);

		if (ret < 0)

			return ret;

	}
@@ -803,11 +802,10 @@ dr_dump_matcher_all(struct seq_file *file, struct mlx5dr_matcher *matcher) 
}



static int

dr_dump_table_rx_tx(struct seq_file *file, bool is_rx,

dr_dump_table_rx_tx(struct seq_file *file, char *buff, bool is_rx,

		    struct mlx5dr_table_rx_tx *table_rx_tx,

		    const u64 table_id)

{

	char buff[MLX5DR_DEBUG_DUMP_BUFF_LENGTH];

	enum dr_dump_rec_type rec_type;

	u64 s_icm_addr;

	int ret;
@@ -829,7 +827,8 @@ dr_dump_table_rx_tx(struct seq_file *file, bool is_rx, 
	return 0;

}



static int dr_dump_table(struct seq_file *file, struct mlx5dr_table *table)

static noinline_for_stack int

dr_dump_table(struct seq_file *file, struct mlx5dr_table *table)

{

	struct mlx5dr_table_rx_tx *rx = &table->rx;

	struct mlx5dr_table_rx_tx *tx = &table->tx;
@@ -848,14 +847,14 @@ static int dr_dump_table(struct seq_file *file, struct mlx5dr_table *table) 
		return ret;



	if (rx->nic_dmn) {

		ret = dr_dump_table_rx_tx(file, true, rx,

		ret = dr_dump_table_rx_tx(file, buff, true, rx,

					  DR_DBG_PTR_TO_ID(table));

		if (ret < 0)

			return ret;

	}



	if (tx->nic_dmn) {

		ret = dr_dump_table_rx_tx(file, false, tx,

		ret = dr_dump_table_rx_tx(file, buff, false, tx,

					  DR_DBG_PTR_TO_ID(table));

		if (ret < 0)

			return ret;
@@ -881,10 +880,10 @@ static int dr_dump_table_all(struct seq_file *file, struct mlx5dr_table *tbl) 
}



static int

dr_dump_send_ring(struct seq_file *file, struct mlx5dr_send_ring *ring,

dr_dump_send_ring(struct seq_file *file, char *buff,

		  struct mlx5dr_send_ring *ring,

		  const u64 domain_id)

{

	char buff[MLX5DR_DEBUG_DUMP_BUFF_LENGTH];

	int ret;



	ret = snprintf(buff, MLX5DR_DEBUG_DUMP_BUFF_LENGTH,
@@ -902,13 +901,13 @@ dr_dump_send_ring(struct seq_file *file, struct mlx5dr_send_ring *ring, 
	return 0;

}



static noinline_for_stack int

static int

dr_dump_domain_info_flex_parser(struct seq_file *file,

				char *buff,

				const char *flex_parser_name,

				const u8 flex_parser_value,

				const u64 domain_id)

{

	char buff[MLX5DR_DEBUG_DUMP_BUFF_LENGTH];

	int ret;



	ret = snprintf(buff, MLX5DR_DEBUG_DUMP_BUFF_LENGTH,
@@ -925,11 +924,11 @@ dr_dump_domain_info_flex_parser(struct seq_file *file, 
	return 0;

}



static noinline_for_stack int

dr_dump_domain_info_caps(struct seq_file *file, struct mlx5dr_cmd_caps *caps,

static int

dr_dump_domain_info_caps(struct seq_file *file, char *buff,

			 struct mlx5dr_cmd_caps *caps,

			 const u64 domain_id)

{

	char buff[MLX5DR_DEBUG_DUMP_BUFF_LENGTH];

	struct mlx5dr_cmd_vport_cap *vport_caps;

	unsigned long i, vports_num;

	int ret;
@@ -969,34 +968,35 @@ dr_dump_domain_info_caps(struct seq_file *file, struct mlx5dr_cmd_caps *caps, 
}



static int

dr_dump_domain_info(struct seq_file *file, struct mlx5dr_domain_info *info,

dr_dump_domain_info(struct seq_file *file, char *buff,

		    struct mlx5dr_domain_info *info,

		    const u64 domain_id)

{

	int ret;



	ret = dr_dump_domain_info_caps(file, &info->caps, domain_id);

	ret = dr_dump_domain_info_caps(file, buff, &info->caps, domain_id);

	if (ret < 0)

		return ret;



	ret = dr_dump_domain_info_flex_parser(file, "icmp_dw0",

	ret = dr_dump_domain_info_flex_parser(file, buff, "icmp_dw0",

					      info->caps.flex_parser_id_icmp_dw0,

					      domain_id);

	if (ret < 0)

		return ret;



	ret = dr_dump_domain_info_flex_parser(file, "icmp_dw1",

	ret = dr_dump_domain_info_flex_parser(file, buff, "icmp_dw1",

					      info->caps.flex_parser_id_icmp_dw1,

					      domain_id);

	if (ret < 0)

		return ret;



	ret = dr_dump_domain_info_flex_parser(file, "icmpv6_dw0",

	ret = dr_dump_domain_info_flex_parser(file, buff, "icmpv6_dw0",

					      info->caps.flex_parser_id_icmpv6_dw0,

					      domain_id);

	if (ret < 0)

		return ret;



	ret = dr_dump_domain_info_flex_parser(file, "icmpv6_dw1",

	ret = dr_dump_domain_info_flex_parser(file, buff, "icmpv6_dw1",

					      info->caps.flex_parser_id_icmpv6_dw1,

					      domain_id);

	if (ret < 0)
@@ -1032,12 +1032,12 @@ dr_dump_domain(struct seq_file *file, struct mlx5dr_domain *dmn) 
	if (ret)

		return ret;



	ret = dr_dump_domain_info(file, &dmn->info, domain_id);

	ret = dr_dump_domain_info(file, buff, &dmn->info, domain_id);

	if (ret < 0)

		return ret;



	if (dmn->info.supp_sw_steering) {

		ret = dr_dump_send_ring(file, dmn->send_ring, domain_id);

		ret = dr_dump_send_ring(file, buff, dmn->send_ring, domain_id);

		if (ret < 0)

			return ret;

	}