From e8f13e061d75ed0eeaaf599532a6b197f195d5f3 Mon Sep 17 00:00:00 2001 From: Justin Stitt Date: Tue, 29 Aug 2023 22:33:16 +0000 Subject: [PATCH] x86/audit: Fix -Wmissing-variable-declarations warning for ia32_xyz_class When building x86 defconfig with Clang-18 I get the following warnings: | arch/x86/ia32/audit.c:6:10: warning: no previous extern declaration for non-static variable 'ia32_dir_class' [-Wmissing-variable-declarations] | 6 | unsigned ia32_dir_class[] = { | arch/x86/ia32/audit.c:11:10: warning: no previous extern declaration for non-static variable 'ia32_chattr_class' [-Wmissing-variable-declarations] | 11 | unsigned ia32_chattr_class[] = { | arch/x86/ia32/audit.c:16:10: warning: no previous extern declaration for non-static variable 'ia32_write_class' [-Wmissing-variable-declarations] | 16 | unsigned ia32_write_class[] = { | arch/x86/ia32/audit.c:21:10: warning: no previous extern declaration for non-static variable 'ia32_read_class' [-Wmissing-variable-declarations] | 21 | unsigned ia32_read_class[] = { | arch/x86/ia32/audit.c:26:10: warning: no previous extern declaration for non-static variable 'ia32_signal_class' [-Wmissing-variable-declarations] | 26 | unsigned ia32_signal_class[] = { These warnings occur due to their respective extern declarations being scoped inside of audit_classes_init as well as only being enabled with `CONFIG_IA32_EMULATION=y`: | static int __init audit_classes_init(void) | { | #ifdef CONFIG_IA32_EMULATION | extern __u32 ia32_dir_class[]; | extern __u32 ia32_write_class[]; | extern __u32 ia32_read_class[]; | extern __u32 ia32_chattr_class[]; | audit_register_class(AUDIT_CLASS_WRITE_32, ia32_write_class); | audit_register_class(AUDIT_CLASS_READ_32, ia32_read_class); | audit_register_class(AUDIT_CLASS_DIR_WRITE_32, ia32_dir_class); | audit_register_class(AUDIT_CLASS_CHATTR_32, ia32_chattr_class); | #endif | audit_register_class(AUDIT_CLASS_WRITE, write_class); | audit_register_class(AUDIT_CLASS_READ, read_class); | audit_register_class(AUDIT_CLASS_DIR_WRITE, dir_class); | audit_register_class(AUDIT_CLASS_CHATTR, chattr_class); | return 0; | } Lift the extern declarations to their own header and resolve scoping issues (and thus fix the warnings). Moreover, change __u32 to unsigned so that we match the definitions: | unsigned ia32_dir_class[] = { | #include | ~0U | }; | | unsigned ia32_chattr_class[] = { | #include | ~0U | }; | ... This patch is similar to commit: 0e5e3d4461a22d73 ("x86/audit: Fix a -Wmissing-prototypes warning for ia32_classify_syscall()") [1] Signed-off-by: Justin Stitt Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/all/20200516123816.2680-1-b.thiel@posteo.de/ [1] Link: https://github.com/ClangBuiltLinux/linux/issues/1920 Link: https://lore.kernel.org/r/20230829-missingvardecl-audit-v1-1-34efeb7f3539@google.com --- arch/x86/include/asm/audit.h | 7 +++++++ arch/x86/kernel/audit_64.c | 5 ----- 2 files changed, 7 insertions(+), 5 deletions(-) diff --git a/arch/x86/include/asm/audit.h b/arch/x86/include/asm/audit.h index 36aec57e..fa918f0 100644 --- a/arch/x86/include/asm/audit.h +++ b/arch/x86/include/asm/audit.h @@ -4,4 +4,11 @@ int ia32_classify_syscall(unsigned int syscall); +extern unsigned ia32_dir_class[]; +extern unsigned ia32_write_class[]; +extern unsigned ia32_read_class[]; +extern unsigned ia32_chattr_class[]; +extern unsigned ia32_signal_class[]; + + #endif /* _ASM_X86_AUDIT_H */ diff --git a/arch/x86/kernel/audit_64.c b/arch/x86/kernel/audit_64.c index 44c3601..190c120 100644 --- a/arch/x86/kernel/audit_64.c +++ b/arch/x86/kernel/audit_64.c @@ -63,11 +63,6 @@ int audit_classify_syscall(int abi, unsigned syscall) static int __init audit_classes_init(void) { #ifdef CONFIG_IA32_EMULATION - extern __u32 ia32_dir_class[]; - extern __u32 ia32_write_class[]; - extern __u32 ia32_read_class[]; - extern __u32 ia32_chattr_class[]; - extern __u32 ia32_signal_class[]; audit_register_class(AUDIT_CLASS_WRITE_32, ia32_write_class); audit_register_class(AUDIT_CLASS_READ_32, ia32_read_class); audit_register_class(AUDIT_CLASS_DIR_WRITE_32, ia32_dir_class); -- 2.7.4