The general version of is_syscall_success does not handle 32-bit
compatible case, which would cause 32-bit negative return code to be
recoganized as a positive number later and seen as a "success".
Since is_compat_thread is defined in compat.h, implementing
is_syscall_success in ptrace.h would introduce build failure due to
recursive inclusion of some basic headers like mutex.h. We put the
implementation to ptrace.c
Signed-off-by: He Zhe <zhe...@windriver.com>
---
arch/arm64/include/asm/ptrace.h | 3 +++
arch/arm64/kernel/ptrace.c | 10 ++++++++++
2 files changed, 13 insertions(+)
diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h
index e58bca832dff..3c415e9e5d85 100644
--- a/arch/arm64/include/asm/ptrace.h
+++ b/arch/arm64/include/asm/ptrace.h
@@ -328,6 +328,9 @@ static inline void regs_set_return_value(struct pt_regs
*regs, unsigned long rc)
regs->regs[0] = rc;
}
+extern inline int is_syscall_success(struct pt_regs *regs);
+#define is_syscall_success(regs) is_syscall_success(regs)
+
/**
* regs_get_kernel_argument() - get Nth function argument in kernel
* @regs: pt_regs of that context
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index 170f42fd6101..3266201f8c60 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -1909,3 +1909,13 @@ int valid_user_regs(struct user_pt_regs *regs, struct
task_struct *task)
else
return valid_native_regs(regs);
}
+
+inline int is_syscall_success(struct pt_regs *regs)
+{
+ unsigned long val = regs->regs[0];
+
+ if (is_compat_thread(task_thread_info(current)))
+ val = sign_extend64(val, 31);
+
+ return !IS_ERR_VALUE(val);
+}
--
2.17.1
