[PATCH v7 07/11] arm64/ptrace: Use syscall_get_arguments() heleper

Jinjie Ruan posted 11 patches 2 weeks ago
There is a newer version of this series
[PATCH v7 07/11] arm64/ptrace: Use syscall_get_arguments() heleper
Posted by Jinjie Ruan 2 weeks ago
The generic entry check audit context first and use
syscall_get_arguments() helper.

In order to switch to the generic entry for arm64,

- Also use the helper.

- Extract the syscall_enter_audit() helper to make it clear.

- Check audit context for syscall_enter_audit(), which only adds
  one additional check without any other differences as
  audit_syscall_entry() check it first otherwise do nothing.

No functional changes.

Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
---
 arch/arm64/kernel/ptrace.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index 9af3046a2ce9..9455ccf1ecc1 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -2376,6 +2376,17 @@ static void report_syscall_exit(struct pt_regs *regs)
 	}
 }
 
+static inline void syscall_enter_audit(struct pt_regs *regs, long syscall)
+{
+	if (unlikely(audit_context())) {
+		unsigned long args[6];
+
+		syscall_get_arguments(current, regs, args);
+		audit_syscall_entry(syscall, args[0], args[1], args[2], args[3]);
+	}
+
+}
+
 int syscall_trace_enter(struct pt_regs *regs, long syscall, unsigned long flags)
 {
 	int ret;
@@ -2406,8 +2417,7 @@ int syscall_trace_enter(struct pt_regs *regs, long syscall, unsigned long flags)
 		 syscall = syscall_get_nr(current, regs);
 	}
 
-	audit_syscall_entry(syscall, regs->orig_x0, regs->regs[1],
-			    regs->regs[2], regs->regs[3]);
+	syscall_enter_audit(regs, syscall);
 
 	return regs->syscallno;
 }
-- 
2.34.1
Re: [PATCH v7 07/11] arm64/ptrace: Use syscall_get_arguments() heleper
Posted by Kevin Brodsky 1 week, 6 days ago
In subject: s/heleper/helper/

On 17/11/2025 14:30, Jinjie Ruan wrote:
> The generic entry check audit context first and use
> syscall_get_arguments() helper.
>
> In order to switch to the generic entry for arm64,
>
> - Also use the helper.
>
> - Extract the syscall_enter_audit() helper to make it clear.
>
> - Check audit context for syscall_enter_audit(), which only adds
>   one additional check without any other differences as
>   audit_syscall_entry() check it first otherwise do nothing.

Presumably this is to avoid an unnecessary memcpy(). Overall these
changes make syscall_enter_audit() exactly equivalent to the generic
one, would be good to spell it out.

> No functional changes.
>
> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
> ---
>  arch/arm64/kernel/ptrace.c | 14 ++++++++++++--
>  1 file changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
> index 9af3046a2ce9..9455ccf1ecc1 100644
> --- a/arch/arm64/kernel/ptrace.c
> +++ b/arch/arm64/kernel/ptrace.c
> @@ -2376,6 +2376,17 @@ static void report_syscall_exit(struct pt_regs *regs)
>  	}
>  }
>  
> +static inline void syscall_enter_audit(struct pt_regs *regs, long syscall)
> +{
> +	if (unlikely(audit_context())) {
> +		unsigned long args[6];
> +
> +		syscall_get_arguments(current, regs, args);
> +		audit_syscall_entry(syscall, args[0], args[1], args[2], args[3]);
> +	}
> +

Nit: empty line.

- Kevin

> +}
> +
>  int syscall_trace_enter(struct pt_regs *regs, long syscall, unsigned long flags)
>  {
>  	int ret;
> @@ -2406,8 +2417,7 @@ int syscall_trace_enter(struct pt_regs *regs, long syscall, unsigned long flags)
>  		 syscall = syscall_get_nr(current, regs);
>  	}
>  
> -	audit_syscall_entry(syscall, regs->orig_x0, regs->regs[1],
> -			    regs->regs[2], regs->regs[3]);
> +	syscall_enter_audit(regs, syscall);
>  
>  	return regs->syscallno;
>  }