[PATCH] scsi: aic94xx: fix use-after-free in device removal path

[moonafterrain]

From: Junrui Luo <moonafterrain@xxxxxxxxxxx>

The asd_pci_remove() function fails to synchronize with pending tasklets
before freeing the asd_ha structure, leading to a potential use-after-free
vulnerability.

When a device removal is triggered (via hot-unplug or module unload), race condition can occur.

The fix adds tasklet_kill() before freeing the asd_ha structure, ensuring
all scheduled tasklets complete before cleanup proceeds.

Reported-by: Yuhao Jiang <danisjiang@xxxxxxxxx>
Reported-by: Junrui Luo <moonafterrain@xxxxxxxxxxx>
Fixes: 2908d778ab3e ("[SCSI] aic94xx: new driver")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Junrui Luo <moonafterrain@xxxxxxxxxxx>
---
 drivers/scsi/aic94xx/aic94xx_init.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/scsi/aic94xx/aic94xx_init.c b/drivers/scsi/aic94xx/aic94xx_init.c
index adf3d9145606..95f3620059f7 100644
--- a/drivers/scsi/aic94xx/aic94xx_init.c
+++ b/drivers/scsi/aic94xx/aic94xx_init.c
@@ -882,6 +882,9 @@ static void asd_pci_remove(struct pci_dev *dev)
 
 	asd_disable_ints(asd_ha);
 
+	/* Ensure all scheduled tasklets complete before freeing resources */
+	tasklet_kill(&asd_ha->seq.dl_tasklet);
+
 	asd_remove_dev_attrs(asd_ha);
 
 	/* XXX more here as needed */
-- 
2.51.1.dirty