uprobes: Do not leak UTASK_BP_HIT if find_active_uprobe() fails

If handle_swbp()->find_active_uprobe() fails we return with
utask->state = UTASK_BP_HIT.

Change handle_swbp() to reset utask->state at the start. Note
that we do this unconditionally, see the next patch(es).

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 912ef48d28ab..2c1ff05af6f5 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1468,6 +1468,10 @@ static void handle_swbp(struct pt_regs *regs)
         bp_vaddr = uprobe_get_swbp_addr(regs);
         uprobe = find_active_uprobe(bp_vaddr, &is_swbp);
 
+        utask = current->utask;
+        if (utask)
+                utask->state = UTASK_RUNNING;
+
         if (!uprobe) {
                 if (is_swbp > 0) {
                         /* No matching uprobe; signal SIGTRAP. */
@@ -1486,7 +1490,6 @@ static void handle_swbp(struct pt_regs *regs)
                 return;
         }
 
-        utask = current->utask;
         if (!utask) {
                 utask = add_utask();
                 /* Cannot allocate; re-execute the instruction. */