[PATCH 03/10] EDAC/altera: Guard against NULL match data in altr_sdram_probe()

[Dinh Nguyen <dinguyen@kernel.org>]

sashiko reports: If a device is manually bound and lacks a valid match entry,
of_match_node() or device_get_match_data() could return NULL.

altr_sdram_probe() dereferenced the pointer returned by of_match_node()
and device_get_match_data() without checking it, which could cause a NULL
pointer dereference when no match data is found. Add a guard that logs
an error and returns -ENODEV.

Assisted-by: Cursor:claude-4.8-opus
Fixes: 143f4a5ac5af ("EDAC, altera: Refactor for Altera CycloneV SoC")
Cc: stable@vger.kernel.org
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
---
 drivers/edac/altera_edac.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c
index 34b33298cf86e..8cbf71ce5d2d8 100644
--- a/drivers/edac/altera_edac.c
+++ b/drivers/edac/altera_edac.c
@@ -300,6 +300,10 @@ static int altr_sdram_probe(struct platform_device *pdev)
 
 	/* Check specific dependencies for the module */
 	priv = device_get_match_data(&pdev->dev);
+	if (!priv) {
+		edac_printk(KERN_ERR, EDAC_MC, "No match data found\n");
+		return -ENODEV;
+	}
 
 	/* Validate the SDRAM controller has ECC enabled */
 	if (regmap_read(mc_vbase, priv->ecc_ctrl_offset, &read_reg) ||
-- 
2.42.0.411.g813d9a9188