| Message ID | 20220105064244.2316847-1-jiasheng@iscas.ac.cn (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | thunderbolt: Check for null pointer after calling kmemdup | expand |
Hi, On Wed, Jan 05, 2022 at 02:42:44PM +0800, Jiasheng Jiang wrote: > As the possible failure of the allocation, kmemdup() may return NULL > pointer. > Like alloc_switch(), it might be better to check it. > Therefore, icm_icl_set_uuid() and icm_handle_event() should also check > the return value of kmemdup(). > As for icm_icl_set_uuid(), which is assigned to icm->set_uuid, the > return value of icm->set_uuid needs to check. > And for icm_handle_event(), just free 'n' and directly return is enough, > same as the way to handle the failure of kmalloc(). This is doing two things so I suggest sending two patches instead. However, for the UUID part, I think it works fine if we get NULL (and I think kmemdup() issues warning too). > Fixes: 3cdb9446a117 ("thunderbolt: Add support for Intel Ice Lake") > Fixes: f67cf491175a ("thunderbolt: Add support for Internal Connection Manager (ICM)") There are probably not needed either since the "fix" here is for pretty rare case of running out of memory. I think there is not even a NULL pointer dereference because UUID is optional. > Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn> > --- > drivers/thunderbolt/icm.c | 20 ++++++++++++++++---- > 1 file changed, 16 insertions(+), 4 deletions(-) > > diff --git a/drivers/thunderbolt/icm.c b/drivers/thunderbolt/icm.c > index 2f30b816705a..09ab31ea9128 100644 > --- a/drivers/thunderbolt/icm.c > +++ b/drivers/thunderbolt/icm.c > @@ -109,7 +109,7 @@ struct icm { > int (*driver_ready)(struct tb *tb, > enum tb_security_level *security_level, > u8 *proto_version, size_t *nboot_acl, bool *rpm); > - void (*set_uuid)(struct tb *tb); > + int (*set_uuid)(struct tb *tb); > void (*device_connected)(struct tb *tb, > const struct icm_pkg_header *hdr); > void (*device_disconnected)(struct tb *tb, > @@ -1643,7 +1643,7 @@ icm_icl_driver_ready(struct tb *tb, enum tb_security_level *security_level, > return 0; > } > > -static void icm_icl_set_uuid(struct tb *tb) > +static int icm_icl_set_uuid(struct tb *tb) > { > struct tb_nhi *nhi = tb->nhi; > u32 uuid[4]; > @@ -1654,6 +1654,10 @@ static void icm_icl_set_uuid(struct tb *tb) > uuid[3] = 0xffffffff; > > tb->root_switch->uuid = kmemdup(uuid, sizeof(uuid), GFP_KERNEL); > + if (!tb->root_switch->uuid) > + return -ENOMEM; > + > + return 0; > } > > static void > @@ -1739,6 +1743,11 @@ static void icm_handle_event(struct tb *tb, enum tb_cfg_pkg_type type, > > INIT_WORK(&n->work, icm_handle_notification); > n->pkg = kmemdup(buf, size, GFP_KERNEL); > + if (!n->pkg) { > + kfree(n); > + return; > + } > + > n->tb = tb; > > queue_work(tb->wq, &n->work); > @@ -2152,8 +2161,11 @@ static int icm_start(struct tb *tb) > tb->root_switch->no_nvm_upgrade = !icm->can_upgrade_nvm; > tb->root_switch->rpm = icm->rpm; > > - if (icm->set_uuid) > - icm->set_uuid(tb); > + if (icm->set_uuid) { > + ret = icm->set_uuid(tb); > + if (ret) > + return ret; > + } > > ret = tb_switch_add(tb->root_switch); > if (ret) { > -- > 2.25.1
diff --git a/drivers/thunderbolt/icm.c b/drivers/thunderbolt/icm.c index 2f30b816705a..09ab31ea9128 100644 --- a/drivers/thunderbolt/icm.c +++ b/drivers/thunderbolt/icm.c @@ -109,7 +109,7 @@ struct icm { int (*driver_ready)(struct tb *tb, enum tb_security_level *security_level, u8 *proto_version, size_t *nboot_acl, bool *rpm); - void (*set_uuid)(struct tb *tb); + int (*set_uuid)(struct tb *tb); void (*device_connected)(struct tb *tb, const struct icm_pkg_header *hdr); void (*device_disconnected)(struct tb *tb, @@ -1643,7 +1643,7 @@ icm_icl_driver_ready(struct tb *tb, enum tb_security_level *security_level, return 0; } -static void icm_icl_set_uuid(struct tb *tb) +static int icm_icl_set_uuid(struct tb *tb) { struct tb_nhi *nhi = tb->nhi; u32 uuid[4]; @@ -1654,6 +1654,10 @@ static void icm_icl_set_uuid(struct tb *tb) uuid[3] = 0xffffffff; tb->root_switch->uuid = kmemdup(uuid, sizeof(uuid), GFP_KERNEL); + if (!tb->root_switch->uuid) + return -ENOMEM; + + return 0; } static void @@ -1739,6 +1743,11 @@ static void icm_handle_event(struct tb *tb, enum tb_cfg_pkg_type type, INIT_WORK(&n->work, icm_handle_notification); n->pkg = kmemdup(buf, size, GFP_KERNEL); + if (!n->pkg) { + kfree(n); + return; + } + n->tb = tb; queue_work(tb->wq, &n->work); @@ -2152,8 +2161,11 @@ static int icm_start(struct tb *tb) tb->root_switch->no_nvm_upgrade = !icm->can_upgrade_nvm; tb->root_switch->rpm = icm->rpm; - if (icm->set_uuid) - icm->set_uuid(tb); + if (icm->set_uuid) { + ret = icm->set_uuid(tb); + if (ret) + return ret; + } ret = tb_switch_add(tb->root_switch); if (ret) {
As the possible failure of the allocation, kmemdup() may return NULL pointer. Like alloc_switch(), it might be better to check it. Therefore, icm_icl_set_uuid() and icm_handle_event() should also check the return value of kmemdup(). As for icm_icl_set_uuid(), which is assigned to icm->set_uuid, the return value of icm->set_uuid needs to check. And for icm_handle_event(), just free 'n' and directly return is enough, same as the way to handle the failure of kmalloc(). Fixes: 3cdb9446a117 ("thunderbolt: Add support for Intel Ice Lake") Fixes: f67cf491175a ("thunderbolt: Add support for Internal Connection Manager (ICM)") Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn> --- drivers/thunderbolt/icm.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-)