| Message ID | 20180726143759.20737.10855.stgit@tlendack-t1.amdoffice.net (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Herbert Xu |
| Headers | show |
| Series | crypto: ccp: Check for NULL PSP pointer at module unload | expand |
On 07/26/2018 09:37 AM, Tom Lendacky wrote: > Should the PSP initialization fail, the PSP data structure will be > freed and the value contained in the sp_device struct set to NULL. > At module unload, psp_dev_destroy() does not check if the pointer > value is NULL and will end up dereferencing a NULL pointer. > > Add a pointer check of the psp_data field in the sp_device struct > in psp_dev_destroy() and return immediately if it is NULL. > > Cc: <stable@vger.kernel.org> # 4.16.x- > Fixes: 2a6170dfe755 ("crypto: ccp: Add Platform Security Processor (PSP) device support") > Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Acked-by: Gary R Hook <gary.hook@amd.com> > --- > drivers/crypto/ccp/psp-dev.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c > index 9b59638..218739b 100644 > --- a/drivers/crypto/ccp/psp-dev.c > +++ b/drivers/crypto/ccp/psp-dev.c > @@ -858,6 +858,9 @@ void psp_dev_destroy(struct sp_device *sp) > { > struct psp_device *psp = sp->psp_data; > > + if (!psp) > + return; > + > if (psp->sev_misc) > kref_put(&misc_dev->refcount, sev_exit); > >
Tom Lendacky <thomas.lendacky@amd.com> wrote: > Should the PSP initialization fail, the PSP data structure will be > freed and the value contained in the sp_device struct set to NULL. > At module unload, psp_dev_destroy() does not check if the pointer > value is NULL and will end up dereferencing a NULL pointer. > > Add a pointer check of the psp_data field in the sp_device struct > in psp_dev_destroy() and return immediately if it is NULL. > > Cc: <stable@vger.kernel.org> # 4.16.x- > Fixes: 2a6170dfe755 ("crypto: ccp: Add Platform Security Processor (PSP) device support") > Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Patch applied. Thanks.
diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c index 9b59638..218739b 100644 --- a/drivers/crypto/ccp/psp-dev.c +++ b/drivers/crypto/ccp/psp-dev.c @@ -858,6 +858,9 @@ void psp_dev_destroy(struct sp_device *sp) { struct psp_device *psp = sp->psp_data; + if (!psp) + return; + if (psp->sev_misc) kref_put(&misc_dev->refcount, sev_exit);
Should the PSP initialization fail, the PSP data structure will be freed and the value contained in the sp_device struct set to NULL. At module unload, psp_dev_destroy() does not check if the pointer value is NULL and will end up dereferencing a NULL pointer. Add a pointer check of the psp_data field in the sp_device struct in psp_dev_destroy() and return immediately if it is NULL. Cc: <stable@vger.kernel.org> # 4.16.x- Fixes: 2a6170dfe755 ("crypto: ccp: Add Platform Security Processor (PSP) device support") Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> --- drivers/crypto/ccp/psp-dev.c | 3 +++ 1 file changed, 3 insertions(+)