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-rw-r--r--arch/riscv/include/asm/syscall.h7
-rw-r--r--arch/riscv/kernel/entry.S11
-rw-r--r--arch/riscv/kernel/ptrace.c11
3 files changed, 8 insertions, 21 deletions
diff --git a/arch/riscv/include/asm/syscall.h b/arch/riscv/include/asm/syscall.h
index 42347d0981e7..49350c8bd7b0 100644
--- a/arch/riscv/include/asm/syscall.h
+++ b/arch/riscv/include/asm/syscall.h
@@ -28,13 +28,6 @@ static inline int syscall_get_nr(struct task_struct *task,
return regs->a7;
}
-static inline void syscall_set_nr(struct task_struct *task,
- struct pt_regs *regs,
- int sysno)
-{
- regs->a7 = sysno;
-}
-
static inline void syscall_rollback(struct task_struct *task,
struct pt_regs *regs)
{
diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S
index bad4d85b5e91..208702d8c18e 100644
--- a/arch/riscv/kernel/entry.S
+++ b/arch/riscv/kernel/entry.S
@@ -229,19 +229,12 @@ check_syscall_nr:
li t0, __NR_syscalls
la s0, sys_ni_syscall
/*
- * The tracer can change syscall number to valid/invalid value.
- * We use syscall_set_nr helper in syscall_trace_enter thus we
- * cannot trust the current value in a7 and have to reload from
- * the current task pt_regs.
- */
- REG_L a7, PT_A7(sp)
- /*
* Syscall number held in a7.
* If syscall number is above allowed value, redirect to ni_syscall.
*/
bge a7, t0, 1f
/*
- * Check if syscall is rejected by tracer or seccomp, i.e., a7 == -1.
+ * Check if syscall is rejected by tracer, i.e., a7 == -1.
* If yes, we pretend it was executed.
*/
li t1, -1
@@ -334,6 +327,7 @@ work_resched:
handle_syscall_trace_enter:
move a0, sp
call do_syscall_trace_enter
+ move t0, a0
REG_L a0, PT_A0(sp)
REG_L a1, PT_A1(sp)
REG_L a2, PT_A2(sp)
@@ -342,6 +336,7 @@ handle_syscall_trace_enter:
REG_L a5, PT_A5(sp)
REG_L a6, PT_A6(sp)
REG_L a7, PT_A7(sp)
+ bnez t0, ret_from_syscall_rejected
j check_syscall_nr
handle_syscall_trace_exit:
move a0, sp
diff --git a/arch/riscv/kernel/ptrace.c b/arch/riscv/kernel/ptrace.c
index 407464201b91..444dc7b0fd78 100644
--- a/arch/riscv/kernel/ptrace.c
+++ b/arch/riscv/kernel/ptrace.c
@@ -148,21 +148,19 @@ long arch_ptrace(struct task_struct *child, long request,
* Allows PTRACE_SYSCALL to work. These are called from entry.S in
* {handle,ret_from}_syscall.
*/
-__visible void do_syscall_trace_enter(struct pt_regs *regs)
+__visible int do_syscall_trace_enter(struct pt_regs *regs)
{
if (test_thread_flag(TIF_SYSCALL_TRACE))
if (tracehook_report_syscall_entry(regs))
- syscall_set_nr(current, regs, -1);
+ return -1;
/*
* Do the secure computing after ptrace; failures should be fast.
* If this fails we might have return value in a0 from seccomp
* (via SECCOMP_RET_ERRNO/TRACE).
*/
- if (secure_computing() == -1) {
- syscall_set_nr(current, regs, -1);
- return;
- }
+ if (secure_computing() == -1)
+ return -1;
#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
@@ -170,6 +168,7 @@ __visible void do_syscall_trace_enter(struct pt_regs *regs)
#endif
audit_syscall_entry(regs->a7, regs->a0, regs->a1, regs->a2, regs->a3);
+ return 0;
}
__visible void do_syscall_trace_exit(struct pt_regs *regs)