diff options
author | Eric W. Biederman <ebiederm@xmission.com> | 2022-04-27 00:30:17 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-06-14 19:11:24 +0300 |
commit | e10356eae1c2a82ff4c382d0ab29adb73b827c8b (patch) | |
tree | 427c8edc479ef7237d0d0abda009b18785b9d5a1 /arch | |
parent | 00c93ce2665c3e81535a726b8d24fd74dbfa6105 (diff) | |
download | linux-e10356eae1c2a82ff4c382d0ab29adb73b827c8b.tar.xz |
ptrace/um: Replace PT_DTRACE with TIF_SINGLESTEP
commit c200e4bb44e80b343c09841e7caaaca0aac5e5fa upstream.
User mode linux is the last user of the PT_DTRACE flag. Using the flag to indicate
single stepping is a little confusing and worse changing tsk->ptrace without locking
could potentionally cause problems.
So use a thread info flag with a better name instead of flag in tsk->ptrace.
Remove the definition PT_DTRACE as uml is the last user.
Cc: stable@vger.kernel.org
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Tested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lkml.kernel.org/r/20220505182645.497868-3-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/um/include/asm/thread_info.h | 2 | ||||
-rw-r--r-- | arch/um/kernel/exec.c | 2 | ||||
-rw-r--r-- | arch/um/kernel/process.c | 2 | ||||
-rw-r--r-- | arch/um/kernel/ptrace.c | 8 | ||||
-rw-r--r-- | arch/um/kernel/signal.c | 4 |
5 files changed, 10 insertions, 8 deletions
diff --git a/arch/um/include/asm/thread_info.h b/arch/um/include/asm/thread_info.h index 4c19ce4c49f1..66ab6a07330b 100644 --- a/arch/um/include/asm/thread_info.h +++ b/arch/um/include/asm/thread_info.h @@ -63,6 +63,7 @@ static inline struct thread_info *current_thread_info(void) #define TIF_RESTORE_SIGMASK 7 #define TIF_NOTIFY_RESUME 8 #define TIF_SECCOMP 9 /* secure computing */ +#define TIF_SINGLESTEP 10 /* single stepping userspace */ #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) @@ -70,5 +71,6 @@ static inline struct thread_info *current_thread_info(void) #define _TIF_MEMDIE (1 << TIF_MEMDIE) #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) #define _TIF_SECCOMP (1 << TIF_SECCOMP) +#define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP) #endif diff --git a/arch/um/kernel/exec.c b/arch/um/kernel/exec.c index e8fd5d540b05..7f7a74c82abb 100644 --- a/arch/um/kernel/exec.c +++ b/arch/um/kernel/exec.c @@ -44,7 +44,7 @@ void start_thread(struct pt_regs *regs, unsigned long eip, unsigned long esp) { PT_REGS_IP(regs) = eip; PT_REGS_SP(regs) = esp; - current->ptrace &= ~PT_DTRACE; + clear_thread_flag(TIF_SINGLESTEP); #ifdef SUBARCH_EXECVE1 SUBARCH_EXECVE1(regs->regs); #endif diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c index 17045e7211bf..d71dd7725bef 100644 --- a/arch/um/kernel/process.c +++ b/arch/um/kernel/process.c @@ -380,7 +380,7 @@ int singlestepping(void * t) { struct task_struct *task = t ? t : current; - if (!(task->ptrace & PT_DTRACE)) + if (!test_thread_flag(TIF_SINGLESTEP)) return 0; if (task->thread.singlestep_syscall) diff --git a/arch/um/kernel/ptrace.c b/arch/um/kernel/ptrace.c index b425f47bddbb..d37802ced563 100644 --- a/arch/um/kernel/ptrace.c +++ b/arch/um/kernel/ptrace.c @@ -12,7 +12,7 @@ void user_enable_single_step(struct task_struct *child) { - child->ptrace |= PT_DTRACE; + set_tsk_thread_flag(child, TIF_SINGLESTEP); child->thread.singlestep_syscall = 0; #ifdef SUBARCH_SET_SINGLESTEPPING @@ -22,7 +22,7 @@ void user_enable_single_step(struct task_struct *child) void user_disable_single_step(struct task_struct *child) { - child->ptrace &= ~PT_DTRACE; + clear_tsk_thread_flag(child, TIF_SINGLESTEP); child->thread.singlestep_syscall = 0; #ifdef SUBARCH_SET_SINGLESTEPPING @@ -121,7 +121,7 @@ static void send_sigtrap(struct uml_pt_regs *regs, int error_code) } /* - * XXX Check PT_DTRACE vs TIF_SINGLESTEP for singlestepping check and + * XXX Check TIF_SINGLESTEP for singlestepping check and * PT_PTRACED vs TIF_SYSCALL_TRACE for syscall tracing check */ int syscall_trace_enter(struct pt_regs *regs) @@ -145,7 +145,7 @@ void syscall_trace_leave(struct pt_regs *regs) audit_syscall_exit(regs); /* Fake a debug trap */ - if (ptraced & PT_DTRACE) + if (test_thread_flag(TIF_SINGLESTEP)) send_sigtrap(®s->regs, 0); if (!test_thread_flag(TIF_SYSCALL_TRACE)) diff --git a/arch/um/kernel/signal.c b/arch/um/kernel/signal.c index 3d57c71c532e..01628195ae52 100644 --- a/arch/um/kernel/signal.c +++ b/arch/um/kernel/signal.c @@ -53,7 +53,7 @@ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) unsigned long sp; int err; - if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED)) + if (test_thread_flag(TIF_SINGLESTEP) && (current->ptrace & PT_PTRACED)) singlestep = 1; /* Did we come from a system call? */ @@ -128,7 +128,7 @@ void do_signal(struct pt_regs *regs) * on the host. The tracing thread will check this flag and * PTRACE_SYSCALL if necessary. */ - if (current->ptrace & PT_DTRACE) + if (test_thread_flag(TIF_SINGLESTEP)) current->thread.singlestep_syscall = is_syscall(PT_REGS_IP(¤t->thread.regs)); |