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From: Michael Buesch <mb@bu3sch.de>
To: John Linville <linville@tuxdriver.com>
Subject: [PATCH] b43legacy: Release mutex in error handling code
Date: Mon, 21 Jul 2008 11:29:34 +0200
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       linux-wireless@vger.kernel.org, jgarzik@pobox.com,
       linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org,
       Julia Lawall <julia@diku.dk>
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From: Julia Lawall <julia@diku.dk>

The mutex is released on a successful return, so it would seem that it
should be released on an error return as well.

The semantic patch finds this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
expression l;
@@

mutex_lock(l);
... when != mutex_unlock(l)
    when any
    when strict
(
if (...) { ... when != mutex_unlock(l)
+   mutex_unlock(l);
    return ...;
}
|
mutex_unlock(l);
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Cc: stable <stable@kernel.org>

---

John, please apply this bugfix to the next bugfix release.

diff -u -p a/drivers/net/wireless/b43legacy/main.c b/drivers/net/wireless/b43legacy/main.c
--- a/drivers/net/wireless/b43legacy/main.c
+++ b/drivers/net/wireless/b43legacy/main.c
@@ -3862,10 +3862,10 @@ static int b43legacy_resume(struct ssb_d
 			goto out;
 		}
 	}
-	mutex_unlock(&wl->mutex);
 
 	b43legacydbg(wl, "Device resumed.\n");
 out:
+	mutex_unlock(&wl->mutex);
 	return err;
 }
 
-- 
Greetings Michael.