2022-10-21 09:45:55

by Xiu Jianfeng

[permalink] [raw]
Subject: [PATCH] apparmor: Fix memleak issue in unpack_profile()

Before aa_alloc_profile(), it has allocated string for @*ns_name if @tmpns
is not NULL, so directly return -ENOMEM if aa_alloc_profile() failed will
cause a memleak issue, and even if aa_alloc_profile() succeed, in the
@fail_profile tag of aa_unpack(), it need to free @ns_name as well, this
patch fixes them.

Fixes: 736ec752d95e ("AppArmor: policy routines for loading and unpacking policy")
Fixes: 04dc715e24d0 ("apparmor: audit policy ns specified in policy load")
Signed-off-by: Xiu Jianfeng <[email protected]>
---
security/apparmor/policy_unpack.c | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/security/apparmor/policy_unpack.c b/security/apparmor/policy_unpack.c
index 2e028d540c6b..1bf8cfb8700a 100644
--- a/security/apparmor/policy_unpack.c
+++ b/security/apparmor/policy_unpack.c
@@ -858,8 +858,11 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
}

profile = aa_alloc_profile(name, NULL, GFP_KERNEL);
- if (!profile)
- return ERR_PTR(-ENOMEM);
+ if (!profile) {
+ info = "out of memory";
+ error = -ENOMEM;
+ goto fail;
+ }
rules = list_first_entry(&profile->rules, typeof(*rules), list);

/* profile renaming is optional */
@@ -1090,6 +1093,10 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
if (error == 0)
/* default error covers most cases */
error = -EPROTO;
+ if (*ns_name) {
+ kfree(*ns_name);
+ *ns_name = NULL;
+ }
if (profile)
name = NULL;
else if (!name)
@@ -1392,6 +1399,7 @@ int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
{
struct aa_load_ent *tmp, *ent;
struct aa_profile *profile = NULL;
+ char *ns_name = NULL;
int error;
struct aa_ext e = {
.start = udata->data,
@@ -1401,7 +1409,6 @@ int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,

*ns = NULL;
while (e.pos < e.end) {
- char *ns_name = NULL;
void *start;
error = verify_header(&e, e.pos == e.start, ns);
if (error)
@@ -1432,6 +1439,7 @@ int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,

ent->new = profile;
ent->ns_name = ns_name;
+ ns_name = NULL;
list_add_tail(&ent->list, lh);
}
udata->abi = e.version & K_ABI_MASK;
@@ -1452,6 +1460,7 @@ int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
return 0;

fail_profile:
+ kfree(ns_name);
aa_put_profile(profile);

fail:
--
2.17.1


2022-10-25 06:14:11

by John Johansen

[permalink] [raw]
Subject: Re: [PATCH] apparmor: Fix memleak issue in unpack_profile()

On 10/21/22 02:36, Xiu Jianfeng wrote:
> Before aa_alloc_profile(), it has allocated string for @*ns_name if @tmpns
> is not NULL, so directly return -ENOMEM if aa_alloc_profile() failed will
> cause a memleak issue, and even if aa_alloc_profile() succeed, in the
> @fail_profile tag of aa_unpack(), it need to free @ns_name as well, this
> patch fixes them.
>
> Fixes: 736ec752d95e ("AppArmor: policy routines for loading and unpacking policy")
> Fixes: 04dc715e24d0 ("apparmor: audit policy ns specified in policy load")
> Signed-off-by: Xiu Jianfeng <[email protected]>

yep thanks I have pulled this into my tree

Acked-by: John Johansen <[email protected]>

> ---
> security/apparmor/policy_unpack.c | 15 ++++++++++++---
> 1 file changed, 12 insertions(+), 3 deletions(-)
>
> diff --git a/security/apparmor/policy_unpack.c b/security/apparmor/policy_unpack.c
> index 2e028d540c6b..1bf8cfb8700a 100644
> --- a/security/apparmor/policy_unpack.c
> +++ b/security/apparmor/policy_unpack.c
> @@ -858,8 +858,11 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
> }
>
> profile = aa_alloc_profile(name, NULL, GFP_KERNEL);
> - if (!profile)
> - return ERR_PTR(-ENOMEM);
> + if (!profile) {
> + info = "out of memory";
> + error = -ENOMEM;
> + goto fail;
> + }
> rules = list_first_entry(&profile->rules, typeof(*rules), list);
>
> /* profile renaming is optional */
> @@ -1090,6 +1093,10 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
> if (error == 0)
> /* default error covers most cases */
> error = -EPROTO;
> + if (*ns_name) {
> + kfree(*ns_name);
> + *ns_name = NULL;
> + }
> if (profile)
> name = NULL;
> else if (!name)
> @@ -1392,6 +1399,7 @@ int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
> {
> struct aa_load_ent *tmp, *ent;
> struct aa_profile *profile = NULL;
> + char *ns_name = NULL;
> int error;
> struct aa_ext e = {
> .start = udata->data,
> @@ -1401,7 +1409,6 @@ int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
>
> *ns = NULL;
> while (e.pos < e.end) {
> - char *ns_name = NULL;
> void *start;
> error = verify_header(&e, e.pos == e.start, ns);
> if (error)
> @@ -1432,6 +1439,7 @@ int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
>
> ent->new = profile;
> ent->ns_name = ns_name;
> + ns_name = NULL;
> list_add_tail(&ent->list, lh);
> }
> udata->abi = e.version & K_ABI_MASK;
> @@ -1452,6 +1460,7 @@ int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
> return 0;
>
> fail_profile:
> + kfree(ns_name);
> aa_put_profile(profile);
>
> fail: