diff options
| author | Sudeep Holla <sudeep.holla@arm.com> | 2019-05-23 10:06:18 +0100 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2019-06-05 17:51:24 +0100 |
| commit | f086f67485c5c126bcec4b0e96ac7319a2e59ab8 (patch) | |
| tree | a2eb3fe5a7af74710dfae1556b8115ef088a14eb | |
| parent | fd3866381be2681395e398c511699fd61a098609 (diff) | |
arm64: ptrace: add support for syscall emulation
Add PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP support on arm64.
We don't need any special handling for PTRACE_SYSEMU_SINGLESTEP.
It's quite difficult to generalize handling PTRACE_SYSEMU cross
architectures and avoid calls to tracehook_report_syscall_entry twice.
Different architecture have different mechanism to indicate NO_SYSCALL
and trying to generalise adds more code for no gain.
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| -rw-r--r-- | arch/arm64/include/asm/thread_info.h | 5 | ||||
| -rw-r--r-- | arch/arm64/kernel/ptrace.c | 6 |
2 files changed, 9 insertions, 2 deletions
diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h index eb3ef73e07cf..c285d1ce7186 100644 --- a/arch/arm64/include/asm/thread_info.h +++ b/arch/arm64/include/asm/thread_info.h @@ -75,6 +75,7 @@ void arch_release_task_struct(struct task_struct *tsk); * TIF_SYSCALL_TRACE - syscall trace active * TIF_SYSCALL_TRACEPOINT - syscall tracepoint for ftrace * TIF_SYSCALL_AUDIT - syscall auditing + * TIF_SYSCALL_EMU - syscall emulation active * TIF_SECOMP - syscall secure computing * TIF_SIGPENDING - signal pending * TIF_NEED_RESCHED - rescheduling necessary @@ -91,6 +92,7 @@ void arch_release_task_struct(struct task_struct *tsk); #define TIF_SYSCALL_AUDIT 9 #define TIF_SYSCALL_TRACEPOINT 10 #define TIF_SECCOMP 11 +#define TIF_SYSCALL_EMU 12 #define TIF_MEMDIE 18 /* is terminating due to OOM killer */ #define TIF_FREEZE 19 #define TIF_RESTORE_SIGMASK 20 @@ -109,6 +111,7 @@ void arch_release_task_struct(struct task_struct *tsk); #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) #define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT) #define _TIF_SECCOMP (1 << TIF_SECCOMP) +#define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU) #define _TIF_UPROBE (1 << TIF_UPROBE) #define _TIF_FSCHECK (1 << TIF_FSCHECK) #define _TIF_32BIT (1 << TIF_32BIT) @@ -120,7 +123,7 @@ void arch_release_task_struct(struct task_struct *tsk); #define _TIF_SYSCALL_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \ _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \ - _TIF_NOHZ) + _TIF_NOHZ | _TIF_SYSCALL_EMU) #define INIT_THREAD_INFO(tsk) \ { \ diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index b82e0a9b3da3..9353355cb91a 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -1819,8 +1819,12 @@ static void tracehook_report_syscall(struct pt_regs *regs, int syscall_trace_enter(struct pt_regs *regs) { - if (test_thread_flag(TIF_SYSCALL_TRACE)) + if (test_thread_flag(TIF_SYSCALL_TRACE) || + test_thread_flag(TIF_SYSCALL_EMU)) { tracehook_report_syscall(regs, PTRACE_SYSCALL_ENTER); + if (!in_syscall(regs) || test_thread_flag(TIF_SYSCALL_EMU)) + return -1; + } /* Do the secure computing after ptrace; failures should be fast. */ if (secure_computing(NULL) == -1) |