From: Oleg Nesterov <oleg@redhat.com>
To: Ananth N Mavinakayanahalli <ananth@in.ibm.com>,
Anton Arapov <arapov@gmail.com>,
David Long <dave.long@linaro.org>,
Denys Vlasenko <dvlasenk@redhat.com>,
"Frank Ch. Eigler" <fche@redhat.com>,
Ingo Molnar <mingo@kernel.org>, Jan Willeke <willeke@de.ibm.com>,
Jim Keniston <jkenisto@us.ibm.com>,
Mark Wielaard <mjw@redhat.com>,
Pratyush Anand <panand@redhat.com>,
Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: linux-kernel@vger.kernel.org
Subject: [PATCH 07/10] uprobes/x86: Introduce arch_uretprobe_is_alive()
Date: Mon, 4 May 2015 14:49:14 +0200 [thread overview]
Message-ID: <20150504124914.GA22512@redhat.com> (raw)
In-Reply-To: <20150504124835.GA22462@redhat.com>
Add the x86-specific arch_uretprobe_is_alive() helper and define its
"weak" version for other architectures.
It returns true if the stack frame mangled by prepare_uretprobe() is
still on stack. So if it returns false, we know that the probed func
has already returned.
TODO: this assumes that the probed app can't use multiple stacks (say
sigaltstack). We will try to improve this logic later.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
---
arch/x86/include/asm/uprobes.h | 1 +
arch/x86/kernel/uprobes.c | 6 ++++++
include/linux/uprobes.h | 1 +
kernel/events/uprobes.c | 4 ++++
4 files changed, 12 insertions(+), 0 deletions(-)
diff --git a/arch/x86/include/asm/uprobes.h b/arch/x86/include/asm/uprobes.h
index f011fd0..60777f3 100644
--- a/arch/x86/include/asm/uprobes.h
+++ b/arch/x86/include/asm/uprobes.h
@@ -57,6 +57,7 @@ struct arch_uprobe {
};
struct arch_uretprobe {
+ unsigned long sp;
};
struct arch_uprobe_task {
diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c
index 0270315..868dc47 100644
--- a/arch/x86/kernel/uprobes.c
+++ b/arch/x86/kernel/uprobes.c
@@ -907,6 +907,7 @@ arch_uretprobe_hijack_return_addr(struct arch_uretprobe *auret,
int rasize = sizeof_long(), nleft;
unsigned long orig_ret_vaddr = 0; /* clear high bits for 32-bit apps */
+ auret->sp = regs->sp;
if (copy_from_user(&orig_ret_vaddr, (void __user *)regs->sp, rasize))
return -1;
@@ -927,3 +928,8 @@ arch_uretprobe_hijack_return_addr(struct arch_uretprobe *auret,
return -1;
}
+
+bool arch_uretprobe_is_alive(struct arch_uretprobe *auret, struct pt_regs *regs)
+{
+ return regs->sp <= auret->sp;
+}
diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h
index 144571b..1ed7502 100644
--- a/include/linux/uprobes.h
+++ b/include/linux/uprobes.h
@@ -129,6 +129,7 @@ extern int arch_uprobe_exception_notify(struct notifier_block *self, unsigned l
extern void arch_uprobe_abort_xol(struct arch_uprobe *aup, struct pt_regs *regs);
extern unsigned long arch_uretprobe_hijack_return_addr(struct arch_uretprobe *auret,
unsigned long trampoline_vaddr, struct pt_regs *regs);
+extern bool arch_uretprobe_is_alive(struct arch_uretprobe *auret, struct pt_regs *regs);
extern bool arch_uprobe_ignore(struct arch_uprobe *aup, struct pt_regs *regs);
extern void arch_uprobe_copy_ixol(struct page *page, unsigned long vaddr,
void *src, unsigned long len);
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 19af44a..0f68ea2 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1820,6 +1820,10 @@ bool __weak arch_uprobe_ignore(struct arch_uprobe *aup, struct pt_regs *regs)
return false;
}
+bool __weak arch_uretprobe_is_alive(struct arch_uretprobe *auret, struct pt_regs *regs)
+{
+ return true;
+}
/*
* Run handler and ask thread to singlestep.
* Ensure all non-fatal signals cannot interrupt thread while it singlesteps.
--
1.5.5.1
next prev parent reply other threads:[~2015-05-04 12:50 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-05-04 12:48 [PATCH 00/10] uprobes: longjmp fixes Oleg Nesterov
2015-05-04 12:48 ` [PATCH 01/10] uprobes: Introduce get_uprobe() Oleg Nesterov
2015-05-06 13:20 ` Srikar Dronamraju
2015-05-04 12:48 ` [PATCH 02/10] uprobes: Introduce free_ret_instance() Oleg Nesterov
2015-05-06 13:22 ` Srikar Dronamraju
2015-05-04 12:48 ` [PATCH 03/10] uprobes: Send SIGILL if handle_trampoline() fails Oleg Nesterov
2015-05-06 13:30 ` Srikar Dronamraju
2015-05-04 12:49 ` [PATCH 04/10] uprobes: Change prepare_uretprobe() to use uprobe_warn() Oleg Nesterov
2015-05-07 10:32 ` Srikar Dronamraju
2015-05-04 12:49 ` [PATCH 05/10] uprobes: Change handle_trampoline() to find the next chain beforehand Oleg Nesterov
2015-05-07 10:33 ` Srikar Dronamraju
2015-05-04 12:49 ` [PATCH 06/10] uprobes: Introduce struct arch_uretprobe Oleg Nesterov
2015-05-07 10:34 ` Srikar Dronamraju
2015-05-04 12:49 ` Oleg Nesterov [this message]
2015-05-07 10:35 ` [PATCH 07/10] uprobes/x86: Introduce arch_uretprobe_is_alive() Srikar Dronamraju
2015-05-07 11:08 ` Srikar Dronamraju
2015-05-07 17:11 ` Oleg Nesterov
2015-05-08 11:30 ` Srikar Dronamraju
2015-05-10 12:21 ` Oleg Nesterov
2015-05-13 8:11 ` Srikar Dronamraju
2015-05-20 16:51 ` Oleg Nesterov
2015-05-18 12:08 ` Pratyush Anand
2015-05-20 15:51 ` Oleg Nesterov
2015-05-04 12:49 ` [PATCH 08/10] uprobes: Change handle_trampoline() to flush the frames invalidated by longjmp() Oleg Nesterov
2015-05-07 10:38 ` Srikar Dronamraju
2015-05-04 12:49 ` [PATCH 09/10] uprobes: Change prepare_uretprobe() to (try to) flush the dead frames Oleg Nesterov
2015-05-07 11:19 ` Srikar Dronamraju
2015-06-05 21:40 ` Oleg Nesterov
2015-05-04 12:49 ` [PATCH 10/10] uprobes/x86: Change arch_uretprobe_is_alive() to take !chained into account Oleg Nesterov
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