[PATCH][next] scsi: target: tcmu: Use struct_size() helper in kmalloc()

From: Gustavo A. R. Silva
Date: Mon Sep 27 2021 - 18:39:48 EST


Make use of the struct_size() helper instead of an open-coded version,
in order to avoid any potential type mistakes or integer overflows
that, in the worst scenario, could lead to heap overflows.

Link: https://github.com/KSPP/linux/issues/160
Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
---
drivers/target/target_core_user.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c
index 9f552f48084c..dc220fad06fa 100644
--- a/drivers/target/target_core_user.c
+++ b/drivers/target/target_core_user.c
@@ -1255,7 +1255,6 @@ tcmu_tmr_notify(struct se_device *se_dev, enum tcm_tmreq_table tmf,
{
int i = 0, cmd_cnt = 0;
bool unqueued = false;
- uint16_t *cmd_ids = NULL;
struct tcmu_cmd *cmd;
struct se_cmd *se_cmd;
struct tcmu_tmr *tmr;
@@ -1292,7 +1291,7 @@ tcmu_tmr_notify(struct se_device *se_dev, enum tcm_tmreq_table tmf,
pr_debug("TMR event %d on dev %s, aborted cmds %d, afflicted cmd_ids %d\n",
tcmu_tmr_type(tmf), udev->name, i, cmd_cnt);

- tmr = kmalloc(sizeof(*tmr) + cmd_cnt * sizeof(*cmd_ids), GFP_NOIO);
+ tmr = kmalloc(struct_size(tmr, tmr_cmd_ids, cmd_cnt), GFP_NOIO);
if (!tmr)
goto unlock;

--
2.27.0