| Message ID | 20210927145332.2784005-1-arnd@kernel.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 34186b48d29bb961b24ece417170e74289550a13 |
| Headers | show |
| Series | [RESEND] ARM: sharpsl_param: work around -Wstringop-overread warning | expand |
On 9/27/21 4:53 PM, Arnd Bergmann wrote: > From: Arnd Bergmann <arnd@arndb.de> > > gcc warns that accessing a pointer based on a numeric constant may > be an offset into a NULL pointer, and would therefore has zero > accessible bytes: > > arch/arm/common/sharpsl_param.c: In function ‘sharpsl_save_param’: > arch/arm/common/sharpsl_param.c:43:9: error: ‘memcpy’ reading 64 bytes from a region of size 0 [-Werror=stringop-overread] > 43 | memcpy(&sharpsl_param, param_start(PARAM_BASE), sizeof(struct sharpsl_param_info)); > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > In this particular case, the warning is bogus since this is the actual > pointer, not an offset on a NULL pointer. Add a local variable to shut > up the warning and hope it doesn't come back. > > Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99578 Acked-by: Daniel Mack <daniel@zonque.org> > Cc: Haojian Zhuang <haojian.zhuang@gmail.com> > Cc: Robert Jarzmik <robert.jarzmik@free.fr> > Cc: Russell King <linux@armlinux.org.uk> > Cc: Linus Walleij <linus.walleij@linaro.org> > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > --- > If there are no objections, I'd apply this one through the soc tree. > --- > arch/arm/common/sharpsl_param.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/arch/arm/common/sharpsl_param.c b/arch/arm/common/sharpsl_param.c > index efeb5724d9e9..6237ede2f0c7 100644 > --- a/arch/arm/common/sharpsl_param.c > +++ b/arch/arm/common/sharpsl_param.c > @@ -40,7 +40,9 @@ EXPORT_SYMBOL(sharpsl_param); > > void sharpsl_save_param(void) > { > - memcpy(&sharpsl_param, param_start(PARAM_BASE), sizeof(struct sharpsl_param_info)); > + struct sharpsl_param_info *params = param_start(PARAM_BASE); > + > + memcpy(&sharpsl_param, params, sizeof(*params)); > > if (sharpsl_param.comadj_keyword != COMADJ_MAGIC) > sharpsl_param.comadj=-1; >
Hello: This patch was applied to soc/soc.git (refs/heads/arm/fixes): On Mon, 27 Sep 2021 16:53:25 +0200 you wrote: > From: Arnd Bergmann <arnd@arndb.de> > > gcc warns that accessing a pointer based on a numeric constant may > be an offset into a NULL pointer, and would therefore has zero > accessible bytes: > > arch/arm/common/sharpsl_param.c: In function ‘sharpsl_save_param’: > arch/arm/common/sharpsl_param.c:43:9: error: ‘memcpy’ reading 64 bytes from a region of size 0 [-Werror=stringop-overread] > 43 | memcpy(&sharpsl_param, param_start(PARAM_BASE), sizeof(struct sharpsl_param_info)); > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > [...] Here is the summary with links: - [RESEND] ARM: sharpsl_param: work around -Wstringop-overread warning https://git.kernel.org/soc/soc/c/34186b48d29b You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
diff --git a/arch/arm/common/sharpsl_param.c b/arch/arm/common/sharpsl_param.c index efeb5724d9e9..6237ede2f0c7 100644 --- a/arch/arm/common/sharpsl_param.c +++ b/arch/arm/common/sharpsl_param.c @@ -40,7 +40,9 @@ EXPORT_SYMBOL(sharpsl_param); void sharpsl_save_param(void) { - memcpy(&sharpsl_param, param_start(PARAM_BASE), sizeof(struct sharpsl_param_info)); + struct sharpsl_param_info *params = param_start(PARAM_BASE); + + memcpy(&sharpsl_param, params, sizeof(*params)); if (sharpsl_param.comadj_keyword != COMADJ_MAGIC) sharpsl_param.comadj=-1;