From: Dan Carpenter dan.carpenter@oracle.com
stable inclusion from stable-5.10.70 commit 91e4ad05bf18322b5921d1a6c9b603f6eb1694f0 bugzilla: 182949 https://gitee.com/openeuler/kernel/issues/I4I3GQ
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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commit 25a1433216489de4abc889910f744e952cb6dbae upstream.
There are two bugs: 1) If ida_simple_get() fails then this code calls put_device(carrier) but we haven't yet called get_device(carrier) and probably that leads to a use after free. 2) After device_initialize() then we need to use put_device() to release the bus. This will free the internal resources tied to the device and call mcb_free_bus() which will free the rest.
Fixes: 5d9e2ab9fea4 ("mcb: Implement bus->dev.release callback") Fixes: 18d288198099 ("mcb: Correctly initialize the bus's device") Cc: stable@vger.kernel.org Signed-off-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Johannes Thumshirn jth@kernel.org Link: https://lore.kernel.org/r/32e160cf6864ce77f9d62948338e24db9fd8ead9.163093131... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Chen Jun chenjun102@huawei.com Acked-by: Weilong Chen chenweilong@huawei.com
Signed-off-by: Chen Jun chenjun102@huawei.com --- drivers/mcb/mcb-core.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/mcb/mcb-core.c b/drivers/mcb/mcb-core.c index 38fbb3b59873..38cc8340e817 100644 --- a/drivers/mcb/mcb-core.c +++ b/drivers/mcb/mcb-core.c @@ -277,8 +277,8 @@ struct mcb_bus *mcb_alloc_bus(struct device *carrier)
bus_nr = ida_simple_get(&mcb_ida, 0, 0, GFP_KERNEL); if (bus_nr < 0) { - rc = bus_nr; - goto err_free; + kfree(bus); + return ERR_PTR(bus_nr); }
bus->bus_nr = bus_nr; @@ -293,12 +293,12 @@ struct mcb_bus *mcb_alloc_bus(struct device *carrier) dev_set_name(&bus->dev, "mcb:%d", bus_nr); rc = device_add(&bus->dev); if (rc) - goto err_free; + goto err_put;
return bus; -err_free: - put_device(carrier); - kfree(bus); + +err_put: + put_device(&bus->dev); return ERR_PTR(rc); } EXPORT_SYMBOL_NS_GPL(mcb_alloc_bus, MCB);