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authorAnanth N Mavinakayanahalli <ananth@in.ibm.com>2007-05-08 00:28:27 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-05-08 11:15:08 -0700
commit0f95b7fc839bc3272b1bf2325d8748a649bd3534 (patch)
treec5cbf5eabc5b58867d7a8949c412163e37182542
parent8f0c45cdf87dc9141e87b0ad2fc6fff216a95f79 (diff)
Kprobes: print details of kretprobe on assertion failure
In certain cases like when the real return address can't be found or when the number of tracked calls to a kretprobed function is less than the number of returns, we may not be able to find the correct return address after processing a kretprobe. Currently we just do a BUG_ON, but no information is provided about the actual failing kretprobe. Print out details of the kretprobe before calling BUG(). Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--arch/i386/kernel/kprobes.c3
-rw-r--r--arch/ia64/kernel/kprobes.c3
-rw-r--r--arch/powerpc/kernel/kprobes.c2
-rw-r--r--arch/x86_64/kernel/kprobes.c2
-rw-r--r--include/linux/kprobes.h10
5 files changed, 15 insertions, 5 deletions
diff --git a/arch/i386/kernel/kprobes.c b/arch/i386/kernel/kprobes.c
index e00f75ecf1a..3fbef288c37 100644
--- a/arch/i386/kernel/kprobes.c
+++ b/arch/i386/kernel/kprobes.c
@@ -449,8 +449,7 @@ fastcall void *__kprobes trampoline_handler(struct pt_regs *regs)
break;
}
- BUG_ON(!orig_ret_address || (orig_ret_address == trampoline_address));
-
+ kretprobe_assert(ri, orig_ret_address, trampoline_address);
spin_unlock_irqrestore(&kretprobe_lock, flags);
hlist_for_each_entry_safe(ri, node, tmp, &empty_rp, hlist) {
diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c
index 779fe00c902..353689edebd 100644
--- a/arch/ia64/kernel/kprobes.c
+++ b/arch/ia64/kernel/kprobes.c
@@ -444,7 +444,8 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
break;
}
- BUG_ON(!orig_ret_address || (orig_ret_address == trampoline_address));
+ kretprobe_assert(ri, orig_ret_address, trampoline_address);
+
regs->cr_iip = orig_ret_address;
reset_current_kprobe();
diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c
index 2a2c696dcc7..3d54ad7dd1f 100644
--- a/arch/powerpc/kernel/kprobes.c
+++ b/arch/powerpc/kernel/kprobes.c
@@ -336,7 +336,7 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
break;
}
- BUG_ON(!orig_ret_address || (orig_ret_address == trampoline_address));
+ kretprobe_assert(ri, orig_ret_address, trampoline_address);
regs->nip = orig_ret_address;
reset_current_kprobe();
diff --git a/arch/x86_64/kernel/kprobes.c b/arch/x86_64/kernel/kprobes.c
index 90e7008cd89..5841ba5f479 100644
--- a/arch/x86_64/kernel/kprobes.c
+++ b/arch/x86_64/kernel/kprobes.c
@@ -447,7 +447,7 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
break;
}
- BUG_ON(!orig_ret_address || (orig_ret_address == trampoline_address));
+ kretprobe_assert(ri, orig_ret_address, trampoline_address);
regs->rip = orig_ret_address;
reset_current_kprobe();
diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index f2646070037..850ee871e35 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -157,6 +157,16 @@ struct kretprobe_instance {
struct task_struct *task;
};
+static inline void kretprobe_assert(struct kretprobe_instance *ri,
+ unsigned long orig_ret_address, unsigned long trampoline_address)
+{
+ if (!orig_ret_address || (orig_ret_address == trampoline_address)) {
+ printk("kretprobe BUG!: Processing kretprobe %p @ %p\n",
+ ri->rp, ri->rp->kp.addr);
+ BUG();
+ }
+}
+
extern spinlock_t kretprobe_lock;
extern struct mutex kprobe_mutex;
extern int arch_prepare_kprobe(struct kprobe *p);