Subject: Re: [PATCH] atm: dereference of he_dev->rbps_virt in he_init_group()

From: Roel Kluin <[email-masked]>
Date: Sun, 20 Sep 2009 19:11:28 +0200

he_dev->rbps_virt or he_dev->rbpl_virt allocation may fail, s
them. Make sure that he_init_group() cleans up after errors.

Signed-off-by: Roel Kluin <[email-masked]>
---

> It looks as if it'd be clearer to not use variable ret and
> simply return -ENOMEM after the out_destroy_rbps_pool label.

Ok, thanks.

Again build, sparse and checkpatch tested.

diff --git a/drivers/atm/he.c b/drivers/atm/he.c
index 2de6406..29e66d6 100644
--- a/drivers/atm/he.c
+++ b/drivers/atm/he.c
@@ -790,11 +790,15 @@ he_init_group(struct he_dev *he_dev, int group)
 	he_dev->rbps_base = pci_alloc_consistent(he_dev->pci_dev,
 		CONFIG_RBPS_SIZE * sizeof(struct he_rbp), &he_dev->rbps_phys);
 	if (he_dev->rbps_base == NULL) {
-		hprintk("failed to alloc rbps\n");
-		return -ENOMEM;
+		hprintk("failed to alloc rbps_base\n");
+		goto out_destroy_rbps_pool;
 	}
 	memset(he_dev->rbps_base, 0, CONFIG_RBPS_SIZE * sizeof(struct he_rbp));
 	he_dev->rbps_virt = kmalloc(CONFIG_RBPS_SIZE * sizeof(struct he_virt), GFP_KERNEL);
+	if (he_dev->rbps_virt == NULL) {
+		hprintk("failed to alloc rbps_virt\n");
+		goto out_free_rbps_base;
+	}
 
 	for (i = 0; i < CONFIG_RBPS_SIZE; ++i) {
 		dma_addr_t dma_handle;
@@ -802,7 +806,7 @@ he_init_group(struct he_dev *he_dev, int group)
 
 		cpuaddr = pci_pool_alloc(he_dev->rbps_pool, GFP_KERNEL|GFP_DMA, &dma_handle);
 		if (cpuaddr == NULL)
-			return -ENOMEM;
+			goto out_free_rbps_virt;
 
 		he_dev->rbps_virt[i].virt = cpuaddr;
 		he_dev->rbps_base[i].status = RBP_LOANED | RBP_SMALLBUF | (i << RBP_INDEX_OFF);
@@ -827,17 +831,21 @@ he_init_group(struct he_dev *he_dev, int group)
 			CONFIG_RBPL_BUFSIZE, 8, 0);
 	if (he_dev->rbpl_pool == NULL) {
 		hprintk("unable to create rbpl pool\n");
-		return -ENOMEM;
+		goto out_free_rbps_virt;
 	}
 
 	he_dev->rbpl_base = pci_alloc_consistent(he_dev->pci_dev,
 		CONFIG_RBPL_SIZE * sizeof(struct he_rbp), &he_dev->rbpl_phys);
 	if (he_dev->rbpl_base == NULL) {
-		hprintk("failed to alloc rbpl\n");
-		return -ENOMEM;
+		hprintk("failed to alloc rbpl_base\n");
+		goto out_destroy_rbpl_pool;
 	}
 	memset(he_dev->rbpl_base, 0, CONFIG_RBPL_SIZE * sizeof(struct he_rbp));
 	he_dev->rbpl_virt = kmalloc(CONFIG_RBPL_SIZE * sizeof(struct he_virt), GFP_KERNEL);
+	if (he_dev->rbpl_virt == NULL) {
+		hprintk("failed to alloc rbpl_virt\n");
+		goto out_free_rbpl_base;
+	}
 
 	for (i = 0; i < CONFIG_RBPL_SIZE; ++i) {
 		dma_addr_t dma_handle;
@@ -845,7 +853,7 @@ he_init_group(struct he_dev *he_dev, int group)
 
 		cpuaddr = pci_pool_alloc(he_dev->rbpl_pool, GFP_KERNEL|GFP_DMA, &dma_handle);
 		if (cpuaddr == NULL)
-			return -ENOMEM;
+			goto out_free_rbpl_virt;
 
 		he_dev->rbpl_virt[i].virt = cpuaddr;
 		he_dev->rbpl_base[i].status = RBP_LOANED | (i << RBP_INDEX_OFF);
@@ -870,7 +878,7 @@ he_init_group(struct he_dev *he_dev, int group)
 		CONFIG_RBRQ_SIZE * sizeof(struct he_rbrq), &he_dev->rbrq_phys);
 	if (he_dev->rbrq_base == NULL) {
 		hprintk("failed to allocate rbrq\n");
-		return -ENOMEM;
+		goto out_free_rbpl_virt;
 	}
 	memset(he_dev->rbrq_base, 0, CONFIG_RBRQ_SIZE * sizeof(struct he_rbrq));
 
@@ -894,7 +902,7 @@ he_init_group(struct he_dev *he_dev, int group)
 		CONFIG_TBRQ_SIZE * sizeof(struct he_tbrq), &he_dev->tbrq_phys);
 	if (he_dev->tbrq_base == NULL) {
 		hprintk("failed to allocate tbrq\n");
-		return -ENOMEM;
+		goto out_free_rbpq_base;
 	}
 	memset(he_dev->tbrq_base, 0, CONFIG_TBRQ_SIZE * sizeof(struct he_tbrq));
 
@@ -906,6 +914,39 @@ he_init_group(struct he_dev *he_dev, int group)
 	he_writel(he_dev, CONFIG_TBRQ_THRESH, G0_TBRQ_THRESH + (group * 16));
 
 	return 0;
+
+out_free_rbpq_base:
+	pci_free_consistent(he_dev->pci_dev, CONFIG_RBRQ_SIZE *
+			sizeof(struct he_rbrq), he_dev->rbrq_base,
+			he_dev->rbrq_phys);
+	i = CONFIG_RBPL_SIZE;
+out_free_rbpl_virt:
+	while (--i)
+		pci_pool_free(he_dev->rbps_pool, he_dev->rbpl_virt[i].virt,
+				he_dev->rbps_base[i].phys);
+	kfree(he_dev->rbpl_virt);
+
+out_free_rbpl_base:
+	pci_free_consistent(he_dev->pci_dev, CONFIG_RBPL_SIZE *
+			sizeof(struct he_rbp), he_dev->rbpl_base,
+			he_dev->rbpl_phys);
+out_destroy_rbpl_pool:
+	pci_pool_destroy(he_dev->rbpl_pool);
+
+	i = CONFIG_RBPL_SIZE;
+out_free_rbps_virt:
+	while (--i)
+		pci_pool_free(he_dev->rbpl_pool, he_dev->rbps_virt[i].virt,
+				he_dev->rbpl_base[i].phys);
+	kfree(he_dev->rbps_virt);
+
+out_free_rbps_base:
+	pci_free_consistent(he_dev->pci_dev, CONFIG_RBPS_SIZE *
+			sizeof(struct he_rbp), he_dev->rbps_base,
+			he_dev->rbps_phys);
+out_destroy_rbps_pool:
+	pci_pool_destroy(he_dev->rbps_pool);
+	return -ENOMEM;
 }
 
 static int __devinit