Commit c0289f67 authored by Shay Drory's avatar Shay Drory Committed by Paolo Abeni
Browse files

net/mlx5: fw_tracer, Handle escaped percent properly 



The firmware tracer's format string validation and parameter counting
did not properly handle escaped percent signs (%%). This caused
fw_tracer to count more parameters when trace format strings contained
literal percent characters.

To fix it, allow %% to pass string validation and skip %% sequences when
counting parameters since they represent literal percent signs rather
than format specifiers.

Fixes: 70dd6fdb ("net/mlx5: FW tracer, parse traces and kernel tracing support")
Signed-off-by: default avatarShay Drory <shayd@nvidia.com>
Reported-by: default avatarBreno Leitao <leitao@debian.org>
Reviewed-by: default avatarMoshe Shemesh <moshe@nvidia.com>
Closes: https://lore.kernel.org/netdev/hanz6rzrb2bqbplryjrakvkbmv4y5jlmtthnvi3thg5slqvelp@t3s3erottr6s/


Signed-off-by: default avatarTariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/1765284977-1363052-5-git-send-email-tariqt@nvidia.com


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent b3596604

drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c

+14 −6
Original line number Diff line number Diff line
@@ -368,11 +368,11 @@ static bool mlx5_is_valid_spec(const char *str) 
	while (isdigit(*str) || *str == '#' || *str == '.' || *str == 'l')

		str++;



	/* Check if it's a valid integer/hex specifier:

	/* Check if it's a valid integer/hex specifier or %%:

	 * Valid formats: %x, %d, %i, %u, etc.

	 */

	if (*str != 'x' && *str != 'X' && *str != 'd' && *str != 'i' &&

	    *str != 'u' && *str != 'c')

	    *str != 'u' && *str != 'c' && *str != '%')

		return false;



	return true;
@@ -390,7 +390,11 @@ static bool mlx5_tracer_validate_params(const char *str) 
		if (!mlx5_is_valid_spec(substr + 1))

			return false;



		if (*(substr + 1) == '%')

			substr = strstr(substr + 2, PARAM_CHAR);

		else

			substr = strstr(substr + 1, PARAM_CHAR);



	}



	return true;
@@ -469,11 +473,15 @@ static int mlx5_tracer_get_num_of_params(char *str) 
		substr = strstr(pstr, VAL_PARM);

	}



	/* count all the % characters */

	/* count all the % characters, but skip %% (escaped percent) */

	substr = strstr(str, PARAM_CHAR);

	while (substr) {

		if (*(substr + 1) != '%') {

			num_of_params += 1;

			str = substr + 1;

		} else {

			str = substr + 2;

		}

		substr = strstr(str, PARAM_CHAR);

	}