2021-12-21 07:10:18

by Jason Wang

Subject: [PATCH] ath10k: replace strlcpy with strscpy

The strlcpy should not be used because it doesn't limit the source
length. So that it will lead some potential bugs.

But the strscpy doesn't require reading memory from the src string
beyond the specified "count" bytes, and since the return value is
easier to error-check than strlcpy()'s. In addition, the implementation
is robust to the string changing out from underneath it, unlike the
current strlcpy() implementation.

Thus, replace strlcpy with strscpy.

Signed-off-by: Jason Wang <[email protected]>
---
drivers/net/wireless/ath/ath10k/coredump.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/ath/ath10k/coredump.c b/drivers/net/wireless/ath/ath10k/coredump.c
index 55e7e11d06d9..fe6b6f97a916 100644
--- a/drivers/net/wireless/ath/ath10k/coredump.c
+++ b/drivers/net/wireless/ath/ath10k/coredump.c
@@ -1522,7 +1522,7 @@ static struct ath10k_dump_file_data *ath10k_coredump_build(struct ath10k *ar)
mutex_lock(&ar->dump_mutex);

dump_data = (struct ath10k_dump_file_data *)(buf);
- strlcpy(dump_data->df_magic, "ATH10K-FW-DUMP",
+ strscpy(dump_data->df_magic, "ATH10K-FW-DUMP",
sizeof(dump_data->df_magic));
dump_data->len = cpu_to_le32(len);

@@ -1543,11 +1543,11 @@ static struct ath10k_dump_file_data *ath10k_coredump_build(struct ath10k *ar)
dump_data->vht_cap_info = cpu_to_le32(ar->vht_cap_info);
dump_data->num_rf_chains = cpu_to_le32(ar->num_rf_chains);

- strlcpy(dump_data->fw_ver, ar->hw->wiphy->fw_version,
+ strscpy(dump_data->fw_ver, ar->hw->wiphy->fw_version,
sizeof(dump_data->fw_ver));

dump_data->kernel_ver_code = 0;
- strlcpy(dump_data->kernel_ver, init_utsname()->release,
+ strscpy(dump_data->kernel_ver, init_utsname()->release,
sizeof(dump_data->kernel_ver));

dump_data->tv_sec = cpu_to_le64(crash_data->timestamp.tv_sec);
--
2.34.1

2021-12-22 06:02:22

by Kalle Valo

Subject: Re: [PATCH] ath10k: replace strlcpy with strscpy

Jason Wang <[email protected]> wrote:

> The strlcpy should not be used because it doesn't limit the source
> length. So that it will lead some potential bugs.
>
> But the strscpy doesn't require reading memory from the src string
> beyond the specified "count" bytes, and since the return value is
> easier to error-check than strlcpy()'s. In addition, the implementation
> is robust to the string changing out from underneath it, unlike the
> current strlcpy() implementation.
>
> Thus, replace strlcpy with strscpy.
>
> Signed-off-by: Jason Wang <[email protected]>
> Signed-off-by: Kalle Valo <[email protected]>

Patch applied to ath-next branch of ath.git, thanks.

9d364b828ae5 ath10k: replace strlcpy with strscpy

--
https://patchwork.kernel.org/project/linux-wireless/patch/[email protected]/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches