syscall_get_arch: add "struct task_struct *" argument

This argument is required to extend the generic ptrace API with
PTRACE_GET_SYSCALL_INFO request: syscall_get_arch() is going
to be called from ptrace_request() along with syscall_get_nr(),
syscall_get_arguments(), syscall_get_error(), and
syscall_get_return_value() functions with a tracee as their argument.

The primary intent is that the triple (audit_arch, syscall_nr, arg1..arg6)
should describe what system call is being called and what its arguments
are.

Reverts: 5e937a9ae913 ("syscall_get_arch: remove useless function arguments")
Reverts: 1002d94d3076 ("syscall.h: fix doc text for syscall_get_arch()")
Reviewed-by: Andy Lutomirski <[email protected]> # for x86
Reviewed-by: Palmer Dabbelt <[email protected]>
Acked-by: Paul Moore <[email protected]>
Acked-by: Paul Burton <[email protected]> # MIPS parts
Acked-by: Michael Ellerman <[email protected]> (powerpc)
Acked-by: Kees Cook <[email protected]> # seccomp parts
Acked-by: Mark Salter <[email protected]> # for the c6x bit
Cc: Elvira Khabirova <[email protected]>
Cc: Eugene Syromyatnikov <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Dmitry V. Levin <[email protected]>
Signed-off-by: Paul Moore <[email protected]>

2 files changed, 4 insertions, 4 deletions

diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 17b0007fafc2..98a98e6dca05 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1636,7 +1636,7 @@ void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2,
 			return;
 	}
 
-	context->arch	    = syscall_get_arch();
+	context->arch	    = syscall_get_arch(current);
 	context->major      = major;
 	context->argv[0]    = a1;
 	context->argv[1]    = a2;
@@ -2590,7 +2590,7 @@ void audit_seccomp(unsigned long syscall, long signr, int code)
 		return;
 	audit_log_task(ab);
 	audit_log_format(ab, " sig=%ld arch=%x syscall=%ld compat=%d ip=0x%lx code=0x%x",
-			 signr, syscall_get_arch(), syscall,
+			 signr, syscall_get_arch(current), syscall,
 			 in_compat_syscall(), KSTK_EIP(current), code);
 	audit_log_end(ab);
 }
diff --git a/kernel/seccomp.c b/kernel/seccomp.c
index 54a0347ca812..36f36ab00f48 100644
--- a/kernel/seccomp.c
+++ b/kernel/seccomp.c
@@ -148,7 +148,7 @@ static void populate_seccomp_data(struct seccomp_data *sd)
 	unsigned long args[6];
 
 	sd->nr = syscall_get_nr(task, regs);
-	sd->arch = syscall_get_arch();
+	sd->arch = syscall_get_arch(task);
 	syscall_get_arguments(task, regs, 0, 6, args);
 	sd->args[0] = args[0];
 	sd->args[1] = args[1];
@@ -591,7 +591,7 @@ static void seccomp_init_siginfo(kernel_siginfo_t *info, int syscall, int reason
 	info->si_code = SYS_SECCOMP;
 	info->si_call_addr = (void __user *)KSTK_EIP(current);
 	info->si_errno = reason;
-	info->si_arch = syscall_get_arch();
+	info->si_arch = syscall_get_arch(current);
 	info->si_syscall = syscall;
 }