[PATCH] posix_acl: fix reference leaks in posix_acl_create

[PATCH] posix_acl: fix reference leaks in posix_acl_create

[Omar Sandoval]

get_acl gets a reference which we must release in the error cases.

Signed-off-by: Omar Sandoval <osandov@osandov.com>
---
 fs/posix_acl.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/posix_acl.c b/fs/posix_acl.c
index 0855f77..f8f3cc2 100644
--- a/fs/posix_acl.c
+++ b/fs/posix_acl.c
@@ -555,28 +555,31 @@ posix_acl_create(struct inode *dir, umode_t *mode,
 	p = get_acl(dir, ACL_TYPE_DEFAULT);
 	if (IS_ERR(p)) {
 		if (p == ERR_PTR(-EOPNOTSUPP))
 			goto apply_umask;
 		return PTR_ERR(p);
 	}
 
 	if (!p)
 		goto apply_umask;
 
 	*acl = posix_acl_clone(p, GFP_NOFS);
-	if (!*acl)
+	if (!*acl) {
+		posix_acl_release(p);
 		return -ENOMEM;
+	}
 
 	ret = posix_acl_create_masq(*acl, mode);
 	if (ret < 0) {
 		posix_acl_release(*acl);
+		posix_acl_release(p);
 		return -ENOMEM;
 	}
 
 	if (ret == 0) {
 		posix_acl_release(*acl);
 		*acl = NULL;
 	}
 
 	if (!S_ISDIR(*mode)) {
 		posix_acl_release(p);
 		*default_acl = NULL;
-- 
2.2.2

Re: [PATCH] posix_acl: fix reference leaks in posix_acl_create

[Christoph Hellwig]

On Mon, Jan 26, 2015 at 10:16:53PM -0800, Omar Sandoval wrote:
> get_acl gets a reference which we must release in the error cases.
> 
> Signed-off-by: Omar Sandoval <osandov@osandov.com>

Looks good, but at this point goto-based unwinding might be in order.

Re: [PATCH] posix_acl: fix reference leaks in posix_acl_create

[Omar Sandoval]

On Wed, Jan 28, 2015 at 06:09:52PM +0100, Christoph Hellwig wrote:
> On Mon, Jan 26, 2015 at 10:16:53PM -0800, Omar Sandoval wrote:
> > get_acl gets a reference which we must release in the error cases.
> > 
> > Signed-off-by: Omar Sandoval <osandov@osandov.com>
> 
> Looks good, but at this point goto-based unwinding might be in order.

Hi, Christoph,

There are already a couple of return paths in posix_acl_create, and
there are only these two error cases, so I think gotos might actually
make the code more confusing. In any case, here's an idea:

posix_acl: fix reference leaks in posix_acl_create

get_acl gets a reference which we must release in the error cases.

Signed-off-by: Omar Sandoval <osandov@osandov.com>

diff --git a/fs/posix_acl.c b/fs/posix_acl.c
index 0855f77..515d315 100644
--- a/fs/posix_acl.c
+++ b/fs/posix_acl.c
@@ -564,13 +564,11 @@ posix_acl_create(struct inode *dir, umode_t *mode,

        *acl = posix_acl_clone(p, GFP_NOFS);
        if (!*acl)
-               return -ENOMEM;
+               goto no_mem;

        ret = posix_acl_create_masq(*acl, mode);
-       if (ret < 0) {
-               posix_acl_release(*acl);
-               return -ENOMEM;
-       }
+       if (ret < 0)
+               goto no_mem_clone;

        if (ret == 0) {
                posix_acl_release(*acl);
@@ -591,6 +589,12 @@ no_acl:
        *default_acl = NULL;
        *acl = NULL;
        return 0;
+
+no_mem_clone:
+       posix_acl_release(*acl);
+no_mem:
+       posix_acl_release(p);
+       return -ENOMEM;
 }
 EXPORT_SYMBOL_GPL(posix_acl_create);

-- 
Omar

Re: [PATCH] posix_acl: fix reference leaks in posix_acl_create

[Christoph Hellwig]

On Sun, Feb 01, 2015 at 11:55:02PM -0800, Omar Sandoval wrote:
> There are already a couple of return paths in posix_acl_create, and
> there are only these two error cases, so I think gotos might actually
> make the code more confusing. In any case, here's an idea:
> 
> posix_acl: fix reference leaks in posix_acl_create
> 
> get_acl gets a reference which we must release in the error cases.
> 
> Signed-off-by: Omar Sandoval <osandov@osandov.com>

Thanks, this one looks good to me.

Reviewed-by: Christoph Hellwig <hch@lst.de>

[PATCH v2] posix_acl: fix reference leaks in posix_acl_create

[Omar Sandoval]

get_acl gets a reference which we must release in the error cases.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
---
Hi, Al,

I'm guessing you're the one to take this one? Just a resend with the
proper format and Christoph's Reviewed-by.

Thanks!

 fs/posix_acl.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/fs/posix_acl.c b/fs/posix_acl.c
index 0855f77..515d315 100644
--- a/fs/posix_acl.c
+++ b/fs/posix_acl.c
@@ -564,13 +564,11 @@ posix_acl_create(struct inode *dir, umode_t *mode,
 
 	*acl = posix_acl_clone(p, GFP_NOFS);
 	if (!*acl)
-		return -ENOMEM;
+		goto no_mem;
 
 	ret = posix_acl_create_masq(*acl, mode);
-	if (ret < 0) {
-		posix_acl_release(*acl);
-		return -ENOMEM;
-	}
+	if (ret < 0)
+		goto no_mem_clone;
 
 	if (ret == 0) {
 		posix_acl_release(*acl);
@@ -591,6 +589,12 @@ no_acl:
 	*default_acl = NULL;
 	*acl = NULL;
 	return 0;
+
+no_mem_clone:
+	posix_acl_release(*acl);
+no_mem:
+	posix_acl_release(p);
+	return -ENOMEM;
 }
 EXPORT_SYMBOL_GPL(posix_acl_create);
 
-- 
2.3.0