From: Shay Drory Date: Tue, 9 Dec 2025 12:56:12 +0000 (+0200) Subject: net/mlx5: fw_tracer, Handle escaped percent properly X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c0289f67f7d6a0dfba0e92cfe661a5c70c8c6e92;p=thirdparty%2Fkernel%2Flinux.git 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: 70dd6fdb8987 ("net/mlx5: FW tracer, parse traces and kernel tracing support") Signed-off-by: Shay Drory Reported-by: Breno Leitao Reviewed-by: Moshe Shemesh Closes: https://lore.kernel.org/netdev/hanz6rzrb2bqbplryjrakvkbmv4y5jlmtthnvi3thg5slqvelp@t3s3erottr6s/ Signed-off-by: Tariq Toukan Link: https://patch.msgid.link/1765284977-1363052-5-git-send-email-tariqt@nvidia.com Signed-off-by: Paolo Abeni --- diff --git a/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c b/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c index b415dfe5de45..6b4ec457ce22 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c @@ -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; - substr = strstr(substr + 1, PARAM_CHAR); + 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) { - num_of_params += 1; - str = substr + 1; + if (*(substr + 1) != '%') { + num_of_params += 1; + str = substr + 1; + } else { + str = substr + 2; + } substr = strstr(str, PARAM_CHAR); }