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 Signed-off-by: Arnd Bergmann arnd@arndb.de --- 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;