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This is a more robust wrapper around sprintf() designed for this purpose. Reported-by: Thomas Wei=C3=9Fschuh Signed-off-by: Ard Biesheuvel --- arch/x86/platform/efi/efi.c | 2 +- drivers/firmware/efi/efi.c | 16 ++++++++-------- 2 files changed, 9 insertions(+), 9 deletions(-) diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index d8fe93770c2a..5eb96c17883e 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -893,7 +893,7 @@ bool efi_is_table_address(unsigned long phys_addr) static ssize_t name##_show(struct kobject *kobj, \ const struct kobj_attribute *attr, char *buf) \ { \ - return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \ + return sysfs_emit(buf, "0x%lx\n", EFI_FIELD(name)); \ } =20 EFI_ATTR_SHOW(fw_vendor); diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 8026264d4990..b4504542cb2c 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -133,26 +133,26 @@ struct kobject *efi_kobj; static ssize_t systab_show(struct kobject *kobj, const struct kobj_attribute *attr, char *buf) { - char *str =3D buf; + int offset =3D 0; =20 if (!kobj || !buf) return -EINVAL; =20 if (efi.acpi20 !=3D EFI_INVALID_TABLE_ADDR) - str +=3D sprintf(str, "ACPI20=3D0x%lx\n", efi.acpi20); + offset =3D sysfs_emit(buf, "ACPI20=3D0x%lx\n", efi.acpi20); if (efi.acpi !=3D EFI_INVALID_TABLE_ADDR) - str +=3D sprintf(str, "ACPI=3D0x%lx\n", efi.acpi); + offset +=3D sysfs_emit_at(buf, offset, "ACPI=3D0x%lx\n", efi.acpi); /* * If both SMBIOS and SMBIOS3 entry points are implemented, the * SMBIOS3 entry point shall be preferred, so we list it first to * let applications stop parsing after the first match. */ if (efi.smbios3 !=3D EFI_INVALID_TABLE_ADDR) - str +=3D sprintf(str, "SMBIOS3=3D0x%lx\n", efi.smbios3); + offset +=3D sysfs_emit_at(buf, offset, "SMBIOS3=3D0x%lx\n", efi.smbios3)= ; if (efi.smbios !=3D EFI_INVALID_TABLE_ADDR) - str +=3D sprintf(str, "SMBIOS=3D0x%lx\n", efi.smbios); + offset +=3D sysfs_emit_at(buf, offset, "SMBIOS=3D0x%lx\n", efi.smbios); =20 - return str - buf; + return offset; } =20 static const struct kobj_attribute efi_attr_systab =3D __KOBJ_ATTR_RO_MODE= (systab, 0400); @@ -160,7 +160,7 @@ static const struct kobj_attribute efi_attr_systab =3D = __KOBJ_ATTR_RO_MODE(systab, static ssize_t fw_platform_size_show(struct kobject *kobj, const struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32); + return sysfs_emit(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32); } =20 extern __weak const struct kobj_attribute efi_attr_fw_vendor; @@ -406,7 +406,7 @@ static ssize_t efi_runtime_show(struct kobject *kobj, const struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%d\n", efi_enabled(EFI_RUNTIME_SERVICES)); + return sysfs_emit(buf, "%d\n", efi_enabled(EFI_RUNTIME_SERVICES)); } =20 static ssize_t efi_runtime_store(struct kobject *kobj, --=20 2.56.0.360.g66cac248cb-goog