From e877b729c649c2850f61f2ae37296ae701f9ad63 Mon Sep 17 00:00:00 2001 From: Heinrich Schuchardt Date: Sun, 8 May 2016 22:50:12 +0200 Subject: [PATCH] usb: gadget: f_tcm: out of bound access in usbg_drop_tpg Commit dc8c46a5ae77 ("usb: gadget: f_tcm: convert to new function interface with backward compatibility") introduced a possible out of bounds memory access: If tpg is not found in function usbg_drop_tpg, tpg_instances[TPG_INSTANCES] is accessed. Fixes: dc8c46a5ae77 ("usb: gadget: f_tcm: convert to new function interface with backward compatibility") Signed-off-by: Heinrich Schuchardt Signed-off-by: Felipe Balbi --- drivers/usb/gadget/function/f_tcm.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/drivers/usb/gadget/function/f_tcm.c b/drivers/usb/gadget/function/f_tcm.c index 35fe3c80cfc0..197f73386fac 100644 --- a/drivers/usb/gadget/function/f_tcm.c +++ b/drivers/usb/gadget/function/f_tcm.c @@ -1445,16 +1445,18 @@ static void usbg_drop_tpg(struct se_portal_group *se_tpg) for (i = 0; i < TPG_INSTANCES; ++i) if (tpg_instances[i].tpg == tpg) break; - if (i < TPG_INSTANCES) + if (i < TPG_INSTANCES) { tpg_instances[i].tpg = NULL; - opts = container_of(tpg_instances[i].func_inst, - struct f_tcm_opts, func_inst); - mutex_lock(&opts->dep_lock); - if (opts->has_dep) - module_put(opts->dependent); - else - configfs_undepend_item_unlocked(&opts->func_inst.group.cg_item); - mutex_unlock(&opts->dep_lock); + opts = container_of(tpg_instances[i].func_inst, + struct f_tcm_opts, func_inst); + mutex_lock(&opts->dep_lock); + if (opts->has_dep) + module_put(opts->dependent); + else + configfs_undepend_item_unlocked( + &opts->func_inst.group.cg_item); + mutex_unlock(&opts->dep_lock); + } mutex_unlock(&tpg_instances_lock); kfree(tpg); -- 2.20.1