Commit 105cd685 authored Mar 14, 2022 by Peter Zijlstra

x86: Mark __invalid_creds() __noreturn



vmlinux.o: warning: objtool: ksys_unshare()+0x36c: unreachable instruction

0000 0000000000067040 <ksys_unshare>:
...
0364    673a4:	4c 89 ef             	mov    %r13,%rdi
0367    673a7:	e8 00 00 00 00       	call   673ac <ksys_unshare+0x36c>	673a8: R_X86_64_PLT32	__invalid_creds-0x4
036c    673ac:	e9 28 ff ff ff       	jmp    672d9 <ksys_unshare+0x299>
0371    673b1:	41 bc f4 ff ff ff    	mov    $0xfffffff4,%r12d
0377    673b7:	e9 80 fd ff ff       	jmp    6713c <ksys_unshare+0xfc>

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/Yi9gOW9f1GGwwUD6@hirez.programming.kicks-ass.net

parent eae654f1

include/linux/cred.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -176,7 +176,7 @@ extern int set_cred_ucounts(struct cred *);
		* check for validity of credentials
		*/
		#ifdef CONFIG_DEBUG_CREDENTIALS
		extern void __invalid_creds(const struct cred , const char , unsigned);
		extern void __noreturn __invalid_creds(const struct cred , const char , unsigned);
		extern void __validate_process_creds(struct task_struct *,
		const char *, unsigned);

kernel/cred.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -870,7 +870,7 @@ static void dump_invalid_creds(const struct cred cred, const char label,
		/*
		* report use of invalid credentials
		*/
		void __invalid_creds(const struct cred cred, const char file, unsigned line)
		void __noreturn __invalid_creds(const struct cred cred, const char file, unsigned line)
		{
		printk(KERN_ERR "CRED: Invalid credentials\n");
		printk(KERN_ERR "CRED: At %s:%u\n", file, line);

tools/objtool/check.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -183,6 +183,7 @@ static bool __dead_end_function(struct objtool_file file, struct symbol func,
		"cpu_bringup_and_idle",
		"do_group_exit",
		"stop_this_cpu",
		"__invalid_creds",
		};

		if (!func)