diff mbox

[3/7] pstore/ram_core: Proper checking for post_init errors (e.g. improper ECC size)

Message ID 1340072156-6225-3-git-send-email-anton.vorontsov@linaro.org
State Accepted
Commit beeb94321a7a6d493b4a06ff0cd771f09f41c35e
Headers show

Commit Message

Anton Vorontsov June 19, 2012, 2:15 a.m. UTC 
We will implement variable-sized ECC buffers soon, so post_init routine
might fail much more likely, so we'd better check for its errors.

To make error handling simple, modify persistent_ram_free() to it be safe
at all times.

Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
---
 fs/pstore/ram_core.c |   22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

Comments

Kees Cook June 19, 2012, 6:41 p.m. UTC | #1 
On Mon, Jun 18, 2012 at 7:15 PM, Anton Vorontsov
<anton.vorontsov@linaro.org> wrote:
> We will implement variable-sized ECC buffers soon, so post_init routine
> might fail much more likely, so we'd better check for its errors.
>
> To make error handling simple, modify persistent_ram_free() to it be safe
> at all times.
>
> Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>

Acked-by: Kees Cook <keescook@chromium.org>
diff mbox

Patch

diff --git a/fs/pstore/ram_core.c b/fs/pstore/ram_core.c
index 2653185..f62ebf2 100644
--- a/fs/pstore/ram_core.c
+++ b/fs/pstore/ram_core.c
@@ -427,11 +427,17 @@  static int __devinit persistent_ram_post_init(struct persistent_ram_zone *prz,
 
 void persistent_ram_free(struct persistent_ram_zone *prz)
 {
-	if (pfn_valid(prz->paddr >> PAGE_SHIFT)) {
-		vunmap(prz->vaddr);
-	} else {
-		iounmap(prz->vaddr);
-		release_mem_region(prz->paddr, prz->size);
+	if (!prz)
+		return;
+
+	if (prz->vaddr) {
+		if (pfn_valid(prz->paddr >> PAGE_SHIFT)) {
+			vunmap(prz->vaddr);
+		} else {
+			iounmap(prz->vaddr);
+			release_mem_region(prz->paddr, prz->size);
+		}
+		prz->vaddr = NULL;
 	}
 	persistent_ram_free_old(prz);
 	kfree(prz);
@@ -454,10 +460,12 @@  struct persistent_ram_zone * __devinit persistent_ram_new(phys_addr_t start,
 	if (ret)
 		goto err;
 
-	persistent_ram_post_init(prz, ecc);
+	ret = persistent_ram_post_init(prz, ecc);
+	if (ret)
+		goto err;
 
 	return prz;
 err:
-	kfree(prz);
+	persistent_ram_free(prz);
 	return ERR_PTR(ret);
 }