From: Emese Revfy <re.emese@gmail.com>
To: dedekind1@gmail.com
Cc: linux-mtd@lists.infradead.org, dwmw2@infradead.org,
linux-kernel@vger.kernel.org
Subject: possible use-after-free in drivers/mtd/ubi/wl.c: erase_worker
Date: Wed, 4 Jan 2012 00:34:46 +0100 [thread overview]
Message-ID: <20120104003446.695fd426@gmail.com> (raw)
Hi,
I think I found a potential problem in drivers/mtd/ubi/wl.c in
erase_worker():
1050 ubi_err("failed to erase PEB %d, error %d", pnum, err);
1051 kfree(wl_wrk);
1052 kmem_cache_free(ubi_wl_entry_slab, e);
1053
1054 if (err == -EINTR || err == -ENOMEM || err == -EAGAIN ||
1055 err == -EBUSY) {
1056 int err1;
1057
1058 /* Re-schedule the LEB for erasure */
1059 err1 = schedule_erase(ubi, e, 0);
The pointer e is freed at line 1052 (kmem_cache_free), but
later it is passed to schedule_erase which will eventually call
erase_worker where it will be dereferenced and/or freed again.
It seems to have been introduced in commit
784c145444e7dd58ae740d406155b72ac658f151
Emese
WARNING: multiple messages have this Message-ID (diff)
From: Emese Revfy <re.emese@gmail.com>
To: dedekind1@gmail.com
Cc: dwmw2@infradead.org, linux-mtd@lists.infradead.org,
linux-kernel@vger.kernel.org
Subject: possible use-after-free in drivers/mtd/ubi/wl.c: erase_worker
Date: Wed, 4 Jan 2012 00:34:46 +0100 [thread overview]
Message-ID: <20120104003446.695fd426@gmail.com> (raw)
Hi,
I think I found a potential problem in drivers/mtd/ubi/wl.c in
erase_worker():
1050 ubi_err("failed to erase PEB %d, error %d", pnum, err);
1051 kfree(wl_wrk);
1052 kmem_cache_free(ubi_wl_entry_slab, e);
1053
1054 if (err == -EINTR || err == -ENOMEM || err == -EAGAIN ||
1055 err == -EBUSY) {
1056 int err1;
1057
1058 /* Re-schedule the LEB for erasure */
1059 err1 = schedule_erase(ubi, e, 0);
The pointer e is freed at line 1052 (kmem_cache_free), but
later it is passed to schedule_erase which will eventually call
erase_worker where it will be dereferenced and/or freed again.
It seems to have been introduced in commit
784c145444e7dd58ae740d406155b72ac658f151
Emese
next reply other threads:[~2012-01-03 23:34 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-03 23:34 Emese Revfy [this message]
2012-01-03 23:34 ` possible use-after-free in drivers/mtd/ubi/wl.c: erase_worker Emese Revfy
2012-01-04 17:33 ` Josh Boyer
2012-01-04 17:33 ` Josh Boyer
2012-01-05 9:14 ` Artem Bityutskiy
2012-01-05 9:14 ` Artem Bityutskiy
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