2016-03-02 10:09:59

by Dan Carpenter

Subject: [patch] tcm_loop: use after free on error

We dereference "tl_nexus" to get the error code.

Fixes: 1b418a8fcbc0 ('target: Convert demo-mode only drivers to target_alloc_session')
Signed-off-by: Dan Carpenter <[email protected]>

diff --git a/drivers/target/loopback/tcm_loop.c b/drivers/target/loopback/tcm_loop.c
index 0216c75..e0ffb03 100644
--- a/drivers/target/loopback/tcm_loop.c
+++ b/drivers/target/loopback/tcm_loop.c
@@ -808,6 +808,7 @@ static int tcm_loop_make_nexus(
{
struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
struct tcm_loop_nexus *tl_nexus;
+ int ret;

if (tl_tpg->tl_nexus) {
pr_debug("tl_tpg->tl_nexus already exists\n");
@@ -824,8 +825,9 @@ static int tcm_loop_make_nexus(
TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
name, tl_nexus, NULL);
if (IS_ERR(tl_nexus->se_sess)) {
+ ret = PTR_ERR(tl_nexus->se_sess);
kfree(tl_nexus);
- return PTR_ERR(tl_nexus->se_sess);
+ return ret;
}

tl_tpg->tl_nexus = tl_nexus;

2016-03-03 13:44:12

by Tomas Henzl

Subject: Re: [patch] tcm_loop: use after free on error

On 2.3.2016 11:09, Dan Carpenter wrote:
> We dereference "tl_nexus" to get the error code.
>
> Fixes: 1b418a8fcbc0 ('target: Convert demo-mode only drivers to target_alloc_session')
> Signed-off-by: Dan Carpenter <[email protected]>

Reviewed-by: Tomas Henzl <[email protected]>

2016-03-05 07:21:22

by Nicholas A. Bellinger

Subject: Re: [patch] tcm_loop: use after free on error

On Wed, 2016-03-02 at 13:09 +0300, Dan Carpenter wrote:
> We dereference "tl_nexus" to get the error code.
>
> Fixes: 1b418a8fcbc0 ('target: Convert demo-mode only drivers to target_alloc_session')
> Signed-off-by: Dan Carpenter <[email protected]>
>
> diff --git a/drivers/target/loopback/tcm_loop.c b/drivers/target/loopback/tcm_loop.c
> index 0216c75..e0ffb03 100644
> --- a/drivers/target/loopback/tcm_loop.c
> +++ b/drivers/target/loopback/tcm_loop.c
> @@ -808,6 +808,7 @@ static int tcm_loop_make_nexus(
> {
> struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
> struct tcm_loop_nexus *tl_nexus;
> + int ret;
>
> if (tl_tpg->tl_nexus) {
> pr_debug("tl_tpg->tl_nexus already exists\n");
> @@ -824,8 +825,9 @@ static int tcm_loop_make_nexus(
> TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
> name, tl_nexus, NULL);
> if (IS_ERR(tl_nexus->se_sess)) {
> + ret = PTR_ERR(tl_nexus->se_sess);
> kfree(tl_nexus);
> - return PTR_ERR(tl_nexus->se_sess);
> + return ret;
> }
>
> tl_tpg->tl_nexus = tl_nexus;

Also fixed + squashed into HCH's original patch.