[PATCH 1/1] uprobes: Fix the wrong usage of current->utask inuprobe_copy_process()

From: Oleg Nesterov
Date: Fri Nov 08 2013 - 10:56:15 EST


Commit aa59c53fd459 "uprobes: Change uprobe_copy_process() to dup
xol_area" has a stupid typo, we need to setup t->utask->vaddr but
the code wrongly uses current->utask.

Even with this bug dup_xol_work() works "in practice", but only
because get_unmapped_area(NULL, TASK_SIZE - PAGE_SIZE) likely
returns the same address every time.

Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
---
kernel/events/uprobes.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 26fdd65..847201f 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1446,7 +1446,7 @@ void uprobe_copy_process(struct task_struct *t, unsigned long flags)
if (!work)
return uprobe_warn(t, "dup xol area");

- utask->vaddr = area->vaddr;
+ t->utask->vaddr = area->vaddr;
init_task_work(work, dup_xol_work);
task_work_add(t, work, true);
}
--
1.5.5.1


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