Commit de66c610 authored Feb 04, 2016 by Jacob Keller Committed by Jeff Kirsher Apr 05, 2016

fm10k: prevent null pointer dereference of msix_entries table



According to the C standard dereferencing a variable before it is
checked invokes undefined behavior, and thus compilers are free to
assume the check for NULL isn't necessary. Prevent this by re-ordering
the NULL check of msix_entries in fm10k_free_mbx_irq.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

parent 11c49f79

drivers/net/ethernet/intel/fm10k/fm10k_pci.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -1143,14 +1143,16 @@ static irqreturn_t fm10k_msix_mbx_pf(int __always_unused irq, void *data)

		void fm10k_mbx_free_irq(struct fm10k_intfc *interface)
		{
		struct msix_entry *entry = &interface->msix_entries[FM10K_MBX_VECTOR];
		struct fm10k_hw *hw = &interface->hw;
		struct msix_entry *entry;
		int itr_reg;

		/* no mailbox IRQ to free if MSI-X is not enabled */
		if (!interface->msix_entries)
		return;

		entry = &interface->msix_entries[FM10K_MBX_VECTOR];

		/* disconnect the mailbox */
		hw->mbx.ops.disconnect(hw, &hw->mbx);