From 5334cdae407a5778a297a98a75ca61140e37ebfa Mon Sep 17 00:00:00 2001 From: Richard Weinberger Date: Sun, 31 May 2015 22:59:03 +0200 Subject: [PATCH] um: Handle tracehook_report_syscall_entry() result tracehook_report_syscall_entry() is allowed to fail, in case of failure we have to abort the current syscall. Signed-off-by: Richard Weinberger --- arch/um/include/asm/ptrace-generic.h | 2 +- arch/um/kernel/ptrace.c | 6 +++--- arch/um/kernel/skas/syscall.c | 6 +++++- 3 files changed, 9 insertions(+), 5 deletions(-) diff --git a/arch/um/include/asm/ptrace-generic.h b/arch/um/include/asm/ptrace-generic.h index cb9b3c47ca8e..283480a7ad23 100644 --- a/arch/um/include/asm/ptrace-generic.h +++ b/arch/um/include/asm/ptrace-generic.h @@ -37,7 +37,7 @@ extern int putreg(struct task_struct *child, int regno, unsigned long value); extern int arch_copy_tls(struct task_struct *new); extern void clear_flushed_tls(struct task_struct *task); -extern void syscall_trace_enter(struct pt_regs *regs); +extern int syscall_trace_enter(struct pt_regs *regs); extern void syscall_trace_leave(struct pt_regs *regs); #endif diff --git a/arch/um/kernel/ptrace.c b/arch/um/kernel/ptrace.c index 174ee5017264..cac2ea058b7a 100644 --- a/arch/um/kernel/ptrace.c +++ b/arch/um/kernel/ptrace.c @@ -131,7 +131,7 @@ static void send_sigtrap(struct task_struct *tsk, struct uml_pt_regs *regs, * XXX Check PT_DTRACE vs TIF_SINGLESTEP for singlestepping check and * PT_PTRACED vs TIF_SYSCALL_TRACE for syscall tracing check */ -void syscall_trace_enter(struct pt_regs *regs) +int syscall_trace_enter(struct pt_regs *regs) { audit_syscall_entry(UPT_SYSCALL_NR(®s->regs), UPT_SYSCALL_ARG1(®s->regs), @@ -140,9 +140,9 @@ void syscall_trace_enter(struct pt_regs *regs) UPT_SYSCALL_ARG4(®s->regs)); if (!test_thread_flag(TIF_SYSCALL_TRACE)) - return; + return 0; - tracehook_report_syscall_entry(regs); + return tracehook_report_syscall_entry(regs); } void syscall_trace_leave(struct pt_regs *regs) diff --git a/arch/um/kernel/skas/syscall.c b/arch/um/kernel/skas/syscall.c index c0681e097432..d9ec0068b623 100644 --- a/arch/um/kernel/skas/syscall.c +++ b/arch/um/kernel/skas/syscall.c @@ -18,7 +18,10 @@ void handle_syscall(struct uml_pt_regs *r) long result; int syscall; - syscall_trace_enter(regs); + if (syscall_trace_enter(regs)) { + result = -ENOSYS; + goto out; + } /* * This should go in the declaration of syscall, but when I do that, @@ -34,6 +37,7 @@ void handle_syscall(struct uml_pt_regs *r) result = -ENOSYS; else result = EXECUTE_SYSCALL(syscall, regs); +out: PT_REGS_SET_SYSCALL_RETURN(regs, result); syscall_trace_leave(regs); -- 2.39.2