From: Yunseong Kim <yskelg@xxxxxxxxx> A null pointer is stored in a local variable after a call of the function "kzalloc" failed. This pointer was passed to a subsequent call of the function "raw3270_setup_device" where an undesirable dereference will be performed then. Thus add corresponding return value checks. The allocated each memory areas are immediately overwritten by the called function zero-initialisation be omitted by calling the "kmalloc" instead. After "ccw_device_enable_console" succeeds, set the bit raw3270 flag to RAW3270_FLAGS_CONSOLE. Fixes: 33403dcfcdfd ("[S390] 3270 console: convert from bootmem to slab") Cc: linux-s390@xxxxxxxxxxxxxxx Signed-off-by: Yunseong Kim <yskelg@xxxxxxxxx> --- drivers/s390/char/raw3270.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/drivers/s390/char/raw3270.c b/drivers/s390/char/raw3270.c index c57694be9bd3..4f3f98bcbc83 100644 --- a/drivers/s390/char/raw3270.c +++ b/drivers/s390/char/raw3270.c @@ -811,18 +811,28 @@ struct raw3270 __init *raw3270_setup_console(void) if (IS_ERR(cdev)) return ERR_CAST(cdev); - rp = kzalloc(sizeof(*rp), GFP_KERNEL | GFP_DMA); - ascebc = kzalloc(256, GFP_KERNEL); + rp = kmalloc(sizeof(*rp), GFP_KERNEL | GFP_DMA); + if (!rp) + return ERR_PTR(-ENOMEM); + ascebc = kmalloc(256, GFP_KERNEL); + if (!ascebc) { + kfree(rp); + return ERR_PTR(-ENOMEM); + } rc = raw3270_setup_device(cdev, rp, ascebc); - if (rc) + if (rc) { + kfree(ascebc); + kfree(rp); return ERR_PTR(rc); - set_bit(RAW3270_FLAGS_CONSOLE, &rp->flags); - + } rc = ccw_device_enable_console(cdev); if (rc) { ccw_device_destroy_console(cdev); + kfree(ascebc); + kfree(rp); return ERR_PTR(rc); } + set_bit(RAW3270_FLAGS_CONSOLE, &rp->flags); spin_lock_irqsave(get_ccwdev_lock(rp->cdev), flags); do { -- 2.45.2