EDAC: Fix kernel panic on module unloading

This patch fixes use-after-free and double-free bugs in
edac_mc_sysfs_exit(). mci_pdev has single reference and put_device()
calls mc_attr_release() which calls kfree(). The following
device_del() works with already released memory. An another kfree() in
edac_mc_sysfs_exit() releses the same memory again. Great.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: stable@vger.kernel.org # 3.[67]
Cc: Denis Kirjanov <kirjanov@gmail.com>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Link: http://lkml.kernel.org/r/20121214110310.11019.21098.stgit@zurg
Signed-off-by: Borislav Petkov <bp@alien8.de>
This commit is contained in:
Konstantin Khlebnikov 2012-12-14 15:03:10 +04:00 committed by Borislav Petkov
parent d1c3ed669a
commit 311bd84247

View File

@ -1159,8 +1159,7 @@ int __init edac_mc_sysfs_init(void)
void __exit edac_mc_sysfs_exit(void)
{
put_device(mci_pdev);
device_del(mci_pdev);
put_device(mci_pdev);
edac_put_sysfs_subsys();
kfree(mci_pdev);
}