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Diffstat (limited to 'arch/x86/kernel/ptrace.c')
-rw-r--r--arch/x86/kernel/ptrace.c57
1 files changed, 26 insertions, 31 deletions
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index b361d28061d..7079ddaf073 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -595,7 +595,7 @@ static unsigned long ptrace_get_dr7(struct perf_event *bp[])
return dr7;
}
-static struct perf_event *
+static int
ptrace_modify_breakpoint(struct perf_event *bp, int len, int type,
struct task_struct *tsk, int disabled)
{
@@ -609,11 +609,11 @@ ptrace_modify_breakpoint(struct perf_event *bp, int len, int type,
* written the address register first
*/
if (!bp)
- return ERR_PTR(-EINVAL);
+ return -EINVAL;
err = arch_bp_generic_fields(len, type, &gen_len, &gen_type);
if (err)
- return ERR_PTR(err);
+ return err;
attr = bp->attr;
attr.bp_len = gen_len;
@@ -658,28 +658,17 @@ restore:
if (!second_pass)
continue;
- thread->ptrace_bps[i] = NULL;
- bp = ptrace_modify_breakpoint(bp, len, type,
+ rc = ptrace_modify_breakpoint(bp, len, type,
tsk, 1);
- if (IS_ERR(bp)) {
- rc = PTR_ERR(bp);
- thread->ptrace_bps[i] = NULL;
+ if (rc)
break;
- }
- thread->ptrace_bps[i] = bp;
}
continue;
}
- bp = ptrace_modify_breakpoint(bp, len, type, tsk, 0);
-
- /* Incorrect bp, or we have a bug in bp API */
- if (IS_ERR(bp)) {
- rc = PTR_ERR(bp);
- thread->ptrace_bps[i] = NULL;
+ rc = ptrace_modify_breakpoint(bp, len, type, tsk, 0);
+ if (rc)
break;
- }
- thread->ptrace_bps[i] = bp;
}
/*
* Make a second pass to free the remaining unused breakpoints
@@ -737,26 +726,32 @@ static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr,
attr.disabled = 1;
bp = register_user_hw_breakpoint(&attr, ptrace_triggered, tsk);
+
+ /*
+ * CHECKME: the previous code returned -EIO if the addr wasn't
+ * a valid task virtual addr. The new one will return -EINVAL in
+ * this case.
+ * -EINVAL may be what we want for in-kernel breakpoints users,
+ * but -EIO looks better for ptrace, since we refuse a register
+ * writing for the user. And anyway this is the previous
+ * behaviour.
+ */
+ if (IS_ERR(bp))
+ return PTR_ERR(bp);
+
+ t->ptrace_bps[nr] = bp;
} else {
+ int err;
+
bp = t->ptrace_bps[nr];
- t->ptrace_bps[nr] = NULL;
attr = bp->attr;
attr.bp_addr = addr;
- bp = modify_user_hw_breakpoint(bp, &attr);
+ err = modify_user_hw_breakpoint(bp, &attr);
+ if (err)
+ return err;
}
- /*
- * CHECKME: the previous code returned -EIO if the addr wasn't a
- * valid task virtual addr. The new one will return -EINVAL in this
- * case.
- * -EINVAL may be what we want for in-kernel breakpoints users, but
- * -EIO looks better for ptrace, since we refuse a register writing
- * for the user. And anyway this is the previous behaviour.
- */
- if (IS_ERR(bp))
- return PTR_ERR(bp);
- t->ptrace_bps[nr] = bp;
return 0;
}