Re: [Xen-devel] [PATCH] libxl/arm: Fix build on arm64 + acpi w/ gcc 8.2
On Tue, Aug 14, 2018 at 01:38:09PM -0700, Christopher Clark wrote: > Add zero-padding to #defined ACPI table strings that are copied. > Provides sufficient characters to satisfy the length required to > fully populate the destination and prevent array-bounds warnings. > > Signed-off-by: Christopher Clark > --- > > Please add this patch to the backport list for the next minor 4.11 > release. > > Prior to this: gcc 8.2 objects to memcpy past bounds: > > | libxl_arm_acpi.c: In function 'make_acpi_header': > | libxl_arm_acpi.c:208:5: error: 'memcpy' forming offset [5, 6] is out > of the bounds [0, 4] [-Werror=array-bounds] > | memcpy(h->oem_id, ACPI_OEM_ID, sizeof(h->oem_id)); > | ^ Please add BUILD_BUG_ON to check the size of oem_id and ACPI_OEM_ID are actually the same. > | libxl_arm_acpi.c:209:5: error: 'memcpy' forming offset [5, 8] is out > of the bounds [0, 4] [-Werror=array-bounds] > | memcpy(h->oem_table_id, ACPI_OEM_TABLE_ID, > sizeof(h->oem_table_id)); > | > ^~~ > | libxl_arm_acpi.c:211:5: error: 'memcpy' forming offset 4 is out of the > bounds [0, 3] [-Werror=array-bounds] > | memcpy(h->asl_compiler_id, ACPI_ASL_COMPILER_ID, > | ^~~~ > | sizeof(h->asl_compiler_id)); > | ~~~ > | In function 'make_acpi_rsdp.isra.4', > | inlined from 'libxl__prepare_acpi' at libxl_arm_acpi.c:389:5: > | libxl_arm_acpi.c:193:5: error: 'memcpy' forming offset [5, 6] is out > of the bounds [0, 4] [-Werror=array-bounds] > | memcpy(rsdp->oem_id, ACPI_OEM_ID, sizeof(rsdp->oem_id)); > | ^~~ > > tools/libxl/libxl_arm_acpi.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/tools/libxl/libxl_arm_acpi.c b/tools/libxl/libxl_arm_acpi.c > index 636f724..eeca1de 100644 > --- a/tools/libxl/libxl_arm_acpi.c > +++ b/tools/libxl/libxl_arm_acpi.c > @@ -48,9 +48,9 @@ extern const unsigned char dsdt_anycpu_arm[]; > _hidden > extern const int dsdt_anycpu_arm_len; > > -#define ACPI_OEM_ID "Xen" > -#define ACPI_OEM_TABLE_ID "ARM" > -#define ACPI_ASL_COMPILER_ID "XL" > +#define ACPI_OEM_ID "Xen\0\0" > +#define ACPI_OEM_TABLE_ID "ARM\0\0\0\0" > +#define ACPI_ASL_COMPILER_ID "XL\0" > > enum { > RSDP, > -- > 2.7.4 > ___ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
Re: [Xen-devel] [PATCH] libxl/arm: Fix build on arm64 + acpi w/ gcc 8.2
On Tue, 14 Aug 2018, Christopher Clark wrote: > Add zero-padding to #defined ACPI table strings that are copied. > Provides sufficient characters to satisfy the length required to > fully populate the destination and prevent array-bounds warnings. > > Signed-off-by: Christopher Clark > --- > > Please add this patch to the backport list for the next minor 4.11 > release. > > Prior to this: gcc 8.2 objects to memcpy past bounds: > > | libxl_arm_acpi.c: In function 'make_acpi_header': > | libxl_arm_acpi.c:208:5: error: 'memcpy' forming offset [5, 6] is out > of the bounds [0, 4] [-Werror=array-bounds] > | memcpy(h->oem_id, ACPI_OEM_ID, sizeof(h->oem_id)); > | ^ > | libxl_arm_acpi.c:209:5: error: 'memcpy' forming offset [5, 8] is out > of the bounds [0, 4] [-Werror=array-bounds] > | memcpy(h->oem_table_id, ACPI_OEM_TABLE_ID, > sizeof(h->oem_table_id)); > | > ^~~ > | libxl_arm_acpi.c:211:5: error: 'memcpy' forming offset 4 is out of the > bounds [0, 3] [-Werror=array-bounds] > | memcpy(h->asl_compiler_id, ACPI_ASL_COMPILER_ID, > | ^~~~ > | sizeof(h->asl_compiler_id)); > | ~~~ > | In function 'make_acpi_rsdp.isra.4', > | inlined from 'libxl__prepare_acpi' at libxl_arm_acpi.c:389:5: > | libxl_arm_acpi.c:193:5: error: 'memcpy' forming offset [5, 6] is out > of the bounds [0, 4] [-Werror=array-bounds] > | memcpy(rsdp->oem_id, ACPI_OEM_ID, sizeof(rsdp->oem_id)); > | ^~~ > > tools/libxl/libxl_arm_acpi.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/tools/libxl/libxl_arm_acpi.c b/tools/libxl/libxl_arm_acpi.c > index 636f724..eeca1de 100644 > --- a/tools/libxl/libxl_arm_acpi.c > +++ b/tools/libxl/libxl_arm_acpi.c > @@ -48,9 +48,9 @@ extern const unsigned char dsdt_anycpu_arm[]; > _hidden > extern const int dsdt_anycpu_arm_len; > > -#define ACPI_OEM_ID "Xen" > -#define ACPI_OEM_TABLE_ID "ARM" > -#define ACPI_ASL_COMPILER_ID "XL" > +#define ACPI_OEM_ID "Xen\0\0" > +#define ACPI_OEM_TABLE_ID "ARM\0\0\0\0" > +#define ACPI_ASL_COMPILER_ID "XL\0" > > enum { > RSDP, Thank you for the patch! These changes should fix the errors. Alternatively, changing the three memcpy's in the following way would also work: memcpy(rsdp->oem_id, ACPI_OEM_ID, sizeof(ACPI_OEM_ID)); I don't have an opinion on which way is best so: Reviewed-by: Stefano Stabellini ___ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
[Xen-devel] [PATCH] libxl/arm: Fix build on arm64 + acpi w/ gcc 8.2
Add zero-padding to #defined ACPI table strings that are copied. Provides sufficient characters to satisfy the length required to fully populate the destination and prevent array-bounds warnings. Signed-off-by: Christopher Clark --- Please add this patch to the backport list for the next minor 4.11 release. Prior to this: gcc 8.2 objects to memcpy past bounds: | libxl_arm_acpi.c: In function 'make_acpi_header': | libxl_arm_acpi.c:208:5: error: 'memcpy' forming offset [5, 6] is out of the bounds [0, 4] [-Werror=array-bounds] | memcpy(h->oem_id, ACPI_OEM_ID, sizeof(h->oem_id)); | ^ | libxl_arm_acpi.c:209:5: error: 'memcpy' forming offset [5, 8] is out of the bounds [0, 4] [-Werror=array-bounds] | memcpy(h->oem_table_id, ACPI_OEM_TABLE_ID, sizeof(h->oem_table_id)); | ^~~ | libxl_arm_acpi.c:211:5: error: 'memcpy' forming offset 4 is out of the bounds [0, 3] [-Werror=array-bounds] | memcpy(h->asl_compiler_id, ACPI_ASL_COMPILER_ID, | ^~~~ | sizeof(h->asl_compiler_id)); | ~~~ | In function 'make_acpi_rsdp.isra.4', | inlined from 'libxl__prepare_acpi' at libxl_arm_acpi.c:389:5: | libxl_arm_acpi.c:193:5: error: 'memcpy' forming offset [5, 6] is out of the bounds [0, 4] [-Werror=array-bounds] | memcpy(rsdp->oem_id, ACPI_OEM_ID, sizeof(rsdp->oem_id)); | ^~~ tools/libxl/libxl_arm_acpi.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/tools/libxl/libxl_arm_acpi.c b/tools/libxl/libxl_arm_acpi.c index 636f724..eeca1de 100644 --- a/tools/libxl/libxl_arm_acpi.c +++ b/tools/libxl/libxl_arm_acpi.c @@ -48,9 +48,9 @@ extern const unsigned char dsdt_anycpu_arm[]; _hidden extern const int dsdt_anycpu_arm_len; -#define ACPI_OEM_ID "Xen" -#define ACPI_OEM_TABLE_ID "ARM" -#define ACPI_ASL_COMPILER_ID "XL" +#define ACPI_OEM_ID "Xen\0\0" +#define ACPI_OEM_TABLE_ID "ARM\0\0\0\0" +#define ACPI_ASL_COMPILER_ID "XL\0" enum { RSDP, -- 2.7.4 ___ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel