2018-08-05 09:49:03

by Xiaoming Ni

Subject: [PATCH] selinuxfs: Fix the resource leak in the failed branch of sel_make_inode

If the resource requested by d_alloc_name is not added to the linked
list through d_add, then dput needs to be called to release the
subsequent abnormal branch to avoid resource leakage.

Add missing dput to selinuxfs.c

Signed-off-by: nixiaoming <[email protected]>
---
security/selinux/selinuxfs.c | 33 +++++++++++++++++++++++++--------
1 file changed, 25 insertions(+), 8 deletions(-)

diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
index 79d3709..0b66d728 100644
--- a/security/selinux/selinuxfs.c
+++ b/security/selinux/selinuxfs.c
@@ -1365,13 +1365,18 @@ static int sel_make_bools(struct selinux_fs_info *fsi)

ret = -ENOMEM;
inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
- if (!inode)
+ if (!inode) {
+ dput(dentry);
goto out;
+ }

ret = -ENAMETOOLONG;
len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
- if (len >= PAGE_SIZE)
+ if (len >= PAGE_SIZE) {
+ dput(dentry);
+ iput(inode);
goto out;
+ }

isec = (struct inode_security_struct *)inode->i_security;
ret = security_genfs_sid(fsi->state, "selinuxfs", page,
@@ -1586,8 +1591,10 @@ static int sel_make_avc_files(struct dentry *dir)
return -ENOMEM;

inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
- if (!inode)
+ if (!inode) {
+ dput(dentry);
return -ENOMEM;
+ }

inode->i_fop = files[i].ops;
inode->i_ino = ++fsi->last_ino;
@@ -1632,8 +1639,10 @@ static int sel_make_initcon_files(struct dentry *dir)
return -ENOMEM;

inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
- if (!inode)
+ if (!inode) {
+ dput(dentry);
return -ENOMEM;
+ }

inode->i_fop = &sel_initcon_ops;
inode->i_ino = i|SEL_INITCON_INO_OFFSET;
@@ -1733,8 +1742,10 @@ static int sel_make_perm_files(char *objclass, int classvalue,

rc = -ENOMEM;
inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
- if (!inode)
+ if (!inode) {
+ dput(dentry);
goto out;
+ }

inode->i_fop = &sel_perm_ops;
/* i+1 since perm values are 1-indexed */
@@ -1763,8 +1774,10 @@ static int sel_make_class_dir_entries(char *classname, int index,
return -ENOMEM;

inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
- if (!inode)
+ if (!inode) {
+ dput(dentry);
return -ENOMEM;
+ }

inode->i_fop = &sel_class_ops;
inode->i_ino = sel_class_to_ino(index);
@@ -1838,8 +1851,10 @@ static int sel_make_policycap(struct selinux_fs_info *fsi)
return -ENOMEM;

inode = sel_make_inode(fsi->sb, S_IFREG | 0444);
- if (inode == NULL)
+ if (inode == NULL) {
+ dput(dentry);
return -ENOMEM;
+ }

inode->i_fop = &sel_policycap_ops;
inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
@@ -1932,8 +1947,10 @@ static int sel_fill_super(struct super_block *sb, void *data, int silent)

ret = -ENOMEM;
inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
- if (!inode)
+ if (!inode) {
+ dput(dentry);
goto err;
+ }

inode->i_ino = ++fsi->last_ino;
isec = (struct inode_security_struct *)inode->i_security;
--
2.10.1

2018-08-07 21:36:36

by Paul Moore

Subject: Re: [PATCH] selinuxfs: Fix the resource leak in the failed branch of sel_make_inode

On Sun, Aug 5, 2018 at 5:48 AM nixiaoming <[email protected]> wrote:
> If the resource requested by d_alloc_name is not added to the linked
> list through d_add, then dput needs to be called to release the
> subsequent abnormal branch to avoid resource leakage.
>
> Add missing dput to selinuxfs.c
>
> Signed-off-by: nixiaoming <[email protected]>
> ---
> security/selinux/selinuxfs.c | 33 +++++++++++++++++++++++++--------
> 1 file changed, 25 insertions(+), 8 deletions(-)

Thanks for the quick follow-up on this patch. It looks okay to me,
assuming my test kernel works correctly (it's building now) I'll merge
this into selinux/next.

> diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
> index 79d3709..0b66d728 100644
> --- a/security/selinux/selinuxfs.c
> +++ b/security/selinux/selinuxfs.c
> @@ -1365,13 +1365,18 @@ static int sel_make_bools(struct selinux_fs_info *fsi)
>
> ret = -ENOMEM;
> inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
> - if (!inode)
> + if (!inode) {
> + dput(dentry);
> goto out;
> + }
>
> ret = -ENAMETOOLONG;
> len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
> - if (len >= PAGE_SIZE)
> + if (len >= PAGE_SIZE) {
> + dput(dentry);
> + iput(inode);
> goto out;
> + }
>
> isec = (struct inode_security_struct *)inode->i_security;
> ret = security_genfs_sid(fsi->state, "selinuxfs", page,
> @@ -1586,8 +1591,10 @@ static int sel_make_avc_files(struct dentry *dir)
> return -ENOMEM;
>
> inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
> - if (!inode)
> + if (!inode) {
> + dput(dentry);
> return -ENOMEM;
> + }
>
> inode->i_fop = files[i].ops;
> inode->i_ino = ++fsi->last_ino;
> @@ -1632,8 +1639,10 @@ static int sel_make_initcon_files(struct dentry *dir)
> return -ENOMEM;
>
> inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
> - if (!inode)
> + if (!inode) {
> + dput(dentry);
> return -ENOMEM;
> + }
>
> inode->i_fop = &sel_initcon_ops;
> inode->i_ino = i|SEL_INITCON_INO_OFFSET;
> @@ -1733,8 +1742,10 @@ static int sel_make_perm_files(char *objclass, int classvalue,
>
> rc = -ENOMEM;
> inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
> - if (!inode)
> + if (!inode) {
> + dput(dentry);
> goto out;
> + }
>
> inode->i_fop = &sel_perm_ops;
> /* i+1 since perm values are 1-indexed */
> @@ -1763,8 +1774,10 @@ static int sel_make_class_dir_entries(char *classname, int index,
> return -ENOMEM;
>
> inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
> - if (!inode)
> + if (!inode) {
> + dput(dentry);
> return -ENOMEM;
> + }
>
> inode->i_fop = &sel_class_ops;
> inode->i_ino = sel_class_to_ino(index);
> @@ -1838,8 +1851,10 @@ static int sel_make_policycap(struct selinux_fs_info *fsi)
> return -ENOMEM;
>
> inode = sel_make_inode(fsi->sb, S_IFREG | 0444);
> - if (inode == NULL)
> + if (inode == NULL) {
> + dput(dentry);
> return -ENOMEM;
> + }
>
> inode->i_fop = &sel_policycap_ops;
> inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
> @@ -1932,8 +1947,10 @@ static int sel_fill_super(struct super_block *sb, void *data, int silent)
>
> ret = -ENOMEM;
> inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
> - if (!inode)
> + if (!inode) {
> + dput(dentry);
> goto err;
> + }
>
> inode->i_ino = ++fsi->last_ino;
> isec = (struct inode_security_struct *)inode->i_security;
> --
> 2.10.1
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-security-module" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html



--
paul moore
http://www.paul-moore.com

2018-08-08 15:41:45

by Paul Moore

Subject: Re: [PATCH] selinuxfs: Fix the resource leak in the failed branch of sel_make_inode

On Tue, Aug 7, 2018 at 5:35 PM Paul Moore <[email protected]> wrote:
>
> On Sun, Aug 5, 2018 at 5:48 AM nixiaoming <[email protected]> wrote:
> > If the resource requested by d_alloc_name is not added to the linked
> > list through d_add, then dput needs to be called to release the
> > subsequent abnormal branch to avoid resource leakage.
> >
> > Add missing dput to selinuxfs.c
> >
> > Signed-off-by: nixiaoming <[email protected]>
> > ---
> > security/selinux/selinuxfs.c | 33 +++++++++++++++++++++++++--------
> > 1 file changed, 25 insertions(+), 8 deletions(-)
>
> Thanks for the quick follow-up on this patch. It looks okay to me,
> assuming my test kernel works correctly (it's building now) I'll merge
> this into selinux/next.

Merged into selinux/next, thanks!

> > diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
> > index 79d3709..0b66d728 100644
> > --- a/security/selinux/selinuxfs.c
> > +++ b/security/selinux/selinuxfs.c
> > @@ -1365,13 +1365,18 @@ static int sel_make_bools(struct selinux_fs_info *fsi)
> >
> > ret = -ENOMEM;
> > inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
> > - if (!inode)
> > + if (!inode) {
> > + dput(dentry);
> > goto out;
> > + }
> >
> > ret = -ENAMETOOLONG;
> > len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
> > - if (len >= PAGE_SIZE)
> > + if (len >= PAGE_SIZE) {
> > + dput(dentry);
> > + iput(inode);
> > goto out;
> > + }
> >
> > isec = (struct inode_security_struct *)inode->i_security;
> > ret = security_genfs_sid(fsi->state, "selinuxfs", page,
> > @@ -1586,8 +1591,10 @@ static int sel_make_avc_files(struct dentry *dir)
> > return -ENOMEM;
> >
> > inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
> > - if (!inode)
> > + if (!inode) {
> > + dput(dentry);
> > return -ENOMEM;
> > + }
> >
> > inode->i_fop = files[i].ops;
> > inode->i_ino = ++fsi->last_ino;
> > @@ -1632,8 +1639,10 @@ static int sel_make_initcon_files(struct dentry *dir)
> > return -ENOMEM;
> >
> > inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
> > - if (!inode)
> > + if (!inode) {
> > + dput(dentry);
> > return -ENOMEM;
> > + }
> >
> > inode->i_fop = &sel_initcon_ops;
> > inode->i_ino = i|SEL_INITCON_INO_OFFSET;
> > @@ -1733,8 +1742,10 @@ static int sel_make_perm_files(char *objclass, int classvalue,
> >
> > rc = -ENOMEM;
> > inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
> > - if (!inode)
> > + if (!inode) {
> > + dput(dentry);
> > goto out;
> > + }
> >
> > inode->i_fop = &sel_perm_ops;
> > /* i+1 since perm values are 1-indexed */
> > @@ -1763,8 +1774,10 @@ static int sel_make_class_dir_entries(char *classname, int index,
> > return -ENOMEM;
> >
> > inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
> > - if (!inode)
> > + if (!inode) {
> > + dput(dentry);
> > return -ENOMEM;
> > + }
> >
> > inode->i_fop = &sel_class_ops;
> > inode->i_ino = sel_class_to_ino(index);
> > @@ -1838,8 +1851,10 @@ static int sel_make_policycap(struct selinux_fs_info *fsi)
> > return -ENOMEM;
> >
> > inode = sel_make_inode(fsi->sb, S_IFREG | 0444);
> > - if (inode == NULL)
> > + if (inode == NULL) {
> > + dput(dentry);
> > return -ENOMEM;
> > + }
> >
> > inode->i_fop = &sel_policycap_ops;
> > inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
> > @@ -1932,8 +1947,10 @@ static int sel_fill_super(struct super_block *sb, void *data, int silent)
> >
> > ret = -ENOMEM;
> > inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
> > - if (!inode)
> > + if (!inode) {
> > + dput(dentry);
> > goto err;
> > + }
> >
> > inode->i_ino = ++fsi->last_ino;
> > isec = (struct inode_security_struct *)inode->i_security;
> > --
> > 2.10.1
> >
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-security-module" in
> > the body of a message to [email protected]
> > More majordomo info at http://vger.kernel.org/majordomo-info.html
>
>
>
> --
> paul moore
> http://www.paul-moore.com



--
paul moore
http://www.paul-moore.com