[PATCH net] net: ibm: emac: mal: fix unchecked platform_get_irq return values

[Rosen Penev]

platform_get_irq() returns a negative errno on failure.
Commit c4f5d0454cab5 moved the platform_get_irq() calls and explicitly
removed the error checks that were previously present, claiming
devm_request_irq() can handle it. However, a negative IRQ number
passed to devm_request_irq() fails with -EINVAL instead of
propagating the real error from platform_get_irq().

Restore the missing error checks with proper errno propagation.

Fixes: c4f5d0454cab5 ("net: ibm: emac: mal: move irq maps down")
Assisted-by: Opencode:Big-Pickle
Signed-off-by: Rosen Penev <rosenp@xxxxxxxxx>
---
 drivers/net/ethernet/ibm/emac/mal.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/net/ethernet/ibm/emac/mal.c b/drivers/net/ethernet/ibm/emac/mal.c
index 7d70056e9008..63a7a32aaf72 100644
--- a/drivers/net/ethernet/ibm/emac/mal.c
+++ b/drivers/net/ethernet/ibm/emac/mal.c
@@ -635,6 +635,12 @@ static int mal_probe(struct platform_device *ofdev)
 	mal->txeob_irq = platform_get_irq(ofdev, 0);
 	mal->rxeob_irq = platform_get_irq(ofdev, 1);
 	mal->serr_irq = platform_get_irq(ofdev, 2);
+	if (mal->txeob_irq < 0 || mal->rxeob_irq < 0 || mal->serr_irq < 0) {
+		err = mal->txeob_irq < 0 ? mal->txeob_irq :
+		      mal->rxeob_irq < 0 ? mal->rxeob_irq : mal->serr_irq;
+		dev_err_probe(&ofdev->dev, err, "failed to get IRQ\n");
+		goto fail2;
+	}
 
 	if (mal_has_feature(mal, MAL_FTR_COMMON_ERR_INT)) {
 		mal->txde_irq = mal->rxde_irq = mal->serr_irq;
@@ -643,6 +649,11 @@ static int mal_probe(struct platform_device *ofdev)
 	} else {
 		mal->txde_irq = platform_get_irq(ofdev, 3);
 		mal->rxde_irq = platform_get_irq(ofdev, 4);
+		if (mal->txde_irq < 0 || mal->rxde_irq < 0) {
+			err = mal->txde_irq < 0 ? mal->txde_irq : mal->rxde_irq;
+			dev_err_probe(&ofdev->dev, err, "failed to get IRQ\n");
+			goto fail2;
+		}
 		irqflags = 0;
 		hdlr_serr = mal_serr;
 		hdlr_txde = mal_txde;
-- 
2.54.0