6.6-stable review patch. If anyone has any objections, please let me know.
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From: Shay Drory shayd@nvidia.com
[ Upstream commit c0289f67f7d6a0dfba0e92cfe661a5c70c8c6e92 ]
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 shayd@nvidia.com Reported-by: Breno Leitao leitao@debian.org Reviewed-by: Moshe Shemesh moshe@nvidia.com Closes: https://lore.kernel.org/netdev/hanz6rzrb2bqbplryjrakvkbmv4y5jlmtthnvi3thg5sl... Signed-off-by: Tariq Toukan tariqt@nvidia.com Link: https://patch.msgid.link/1765284977-1363052-5-git-send-email-tariqt@nvidia.c... Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- .../mellanox/mlx5/core/diag/fw_tracer.c | 20 +++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-)
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 197c306d350bf..0a33ab5f53fd3 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); }