diff mbox series

mac80211: Replace strlcpy with strscpy

Message ID 20230613003404.3538524-1-azeemshaikh38@gmail.com (mailing list archive)
State Awaiting Upstream
Delegated to: Netdev Maintainers
Headers show
Series mac80211: Replace strlcpy with strscpy | expand

Checks

Context Check Description
netdev/series_format warning Single patches do not need cover letters; Target tree name not specified in the subject
netdev/tree_selection success Guessed tree name to be net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 8 this patch: 8
netdev/cc_maintainers success CCed 7 of 7 maintainers
netdev/build_clang success Errors and warnings before: 8 this patch: 8
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 8 this patch: 8
netdev/checkpatch warning WARNING: line length of 90 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Azeem Shaikh June 13, 2023, 12:34 a.m. UTC
strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().

Direct replacement is safe here since LOCAL_ASSIGN is only used by
TRACE macros and the return values are ignored.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
---
 net/mac80211/trace.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Kees Cook June 13, 2023, 7:25 p.m. UTC | #1
On Tue, Jun 13, 2023 at 12:34:04AM +0000, Azeem Shaikh wrote:
> strlcpy() reads the entire source buffer first.
> This read may exceed the destination size limit.
> This is both inefficient and can lead to linear read
> overflows if a source string is not NUL-terminated [1].
> In an effort to remove strlcpy() completely [2], replace
> strlcpy() here with strscpy().
> 
> Direct replacement is safe here since LOCAL_ASSIGN is only used by
> TRACE macros and the return values are ignored.
> 
> [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
> [2] https://github.com/KSPP/linux/issues/89
> 
> Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>

Reviewed-by: Kees Cook <keescook@chromium.org>
Simon Horman June 14, 2023, 12:09 p.m. UTC | #2
On Tue, Jun 13, 2023 at 12:34:04AM +0000, Azeem Shaikh wrote:
> strlcpy() reads the entire source buffer first.
> This read may exceed the destination size limit.
> This is both inefficient and can lead to linear read
> overflows if a source string is not NUL-terminated [1].
> In an effort to remove strlcpy() completely [2], replace
> strlcpy() here with strscpy().
> 
> Direct replacement is safe here since LOCAL_ASSIGN is only used by
> TRACE macros and the return values are ignored.
> 
> [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
> [2] https://github.com/KSPP/linux/issues/89
> 
> Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>

Reviewed-by: Simon Horman <simon.horman@corigine.com>
diff mbox series

Patch

diff --git a/net/mac80211/trace.h b/net/mac80211/trace.h
index db0d0132c58c..c51c6e3feac9 100644
--- a/net/mac80211/trace.h
+++ b/net/mac80211/trace.h
@@ -17,7 +17,7 @@ 
 
 #define MAXNAME		32
 #define LOCAL_ENTRY	__array(char, wiphy_name, 32)
-#define LOCAL_ASSIGN	strlcpy(__entry->wiphy_name, wiphy_name(local->hw.wiphy), MAXNAME)
+#define LOCAL_ASSIGN	strscpy(__entry->wiphy_name, wiphy_name(local->hw.wiphy), MAXNAME)
 #define LOCAL_PR_FMT	"%s"
 #define LOCAL_PR_ARG	__entry->wiphy_name