[PATCH v4] soc/fsl/qe: fix err handling of ucc_of_parse_tdm
From: Peng Hao
Date: Sat Dec 29 2018 - 03:27:23 EST
From: Wen Yang <wen.yang99@xxxxxxxxxx>
Currently there are some issues with the ucc_of_parse_tdm function:
1, a possible null pointer dereference in ucc_of_parse_tdm,
detected by the semantic patch deref_null.cocci,
with the following warning:
drivers/soc/fsl/qe/qe_tdm.c:177:21-24: ERROR: pdev is NULL but dereferenced.
2, dev gets modified, so in any case that devm_iounmap() will fail
even when the new pdev is valid, because the iomap was done with a
different pdev.
3, there is no driver bind with the "fsl,t1040-qe-si" or
"fsl,t1040-qe-siram" device. So allocating resources using devm_*()
with these devices won't provide a cleanup path for these resources
when the caller fails.
This patch fixes them.
Suggested-by: Li Yang <leoyang.li@xxxxxxx>
Suggested-by: Christophe LEROY <christophe.leroy@xxxxxx>
Signed-off-by: Wen Yang <wen.yang99@xxxxxxxxxx>
Reviewed-by: Peng Hao <peng.hao2@xxxxxxxxxx>
CC: Julia Lawall <julia.lawall@xxxxxxx>
CC: Zhao Qiang <qiang.zhao@xxxxxxx>
CC: David S. Miller <davem@xxxxxxxxxxxxx>
CC: netdev@xxxxxxxxxxxxxxx
CC: linuxppc-dev@xxxxxxxxxxxxxxxx
CC: linux-kernel@xxxxxxxxxxxxxxx
---
drivers/net/wan/fsl_ucc_hdlc.c | 52 ++++++++++++++++++++++++++++++++++++++-
drivers/soc/fsl/qe/qe_tdm.c | 55 ------------------------------------------
2 files changed, 51 insertions(+), 56 deletions(-)
diff --git a/drivers/net/wan/fsl_ucc_hdlc.c b/drivers/net/wan/fsl_ucc_hdlc.c
index 839fa77..07a496c 100644
--- a/drivers/net/wan/fsl_ucc_hdlc.c
+++ b/drivers/net/wan/fsl_ucc_hdlc.c
@@ -1057,6 +1057,26 @@ static const struct net_device_ops uhdlc_ops = {
.ndo_tx_timeout = uhdlc_tx_timeout,
};
+static struct resource *ucc_get_resource_by_nodename(char *name)
+{
+ struct device_node *np;
+ struct platform_device *pdev;
+
+ np = of_find_compatible_node(NULL, NULL, name);
+ if (!np)
+ return ERR_PTR(-EINVAL);
+
+ pdev = of_find_device_by_node(np);
+ if (!pdev) {
+ pr_err("%pOFn: failed to lookup pdev\n", np);
+ of_node_put(np);
+ return ERR_PTR(-EINVAL);
+ }
+
+ of_node_put(np);
+ return platform_get_resource(pdev, IORESOURCE_MEM, 0);
+}
+
static int ucc_hdlc_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
@@ -1070,6 +1090,8 @@ static int ucc_hdlc_probe(struct platform_device *pdev)
const char *sprop;
int ret;
u32 val;
+ struct resource *r_mem;
+ static int siram_init_flag;
ret = of_property_read_u32_index(np, "cell-index", 0, &val);
if (ret) {
@@ -1151,6 +1173,31 @@ static int ucc_hdlc_probe(struct platform_device *pdev)
ret = ucc_of_parse_tdm(np, utdm, ut_info);
if (ret)
goto free_utdm;
+
+ r_mem = ucc_get_resource_by_nodename("fsl,t1040-qe-si");
+ if (IS_ERR_OR_NULL(r_mem)) {
+ ret = -EINVAL;
+ goto free_utdm;
+ }
+ utdm->si_regs = ioremap(r_mem->start, resource_size(r_mem));
+ if (!utdm->si_regs) {
+ ret = -ENOMEM;
+ goto free_utdm;
+ }
+ r_mem = ucc_get_resource_by_nodename("fsl,t1040-qe-siram");
+ if (IS_ERR_OR_NULL(r_mem)) {
+ ret = -EINVAL;
+ goto unmap_si_regs;
+ }
+ utdm->siram = ioremap(r_mem->start, resource_size(r_mem));
+ if (!utdm->siram) {
+ ret = -ENOMEM;
+ goto unmap_si_regs;
+ }
+ if (siram_init_flag == 0) {
+ memset_io(utdm->siram, 0, resource_size(r_mem));
+ siram_init_flag = 1;
+ }
}
if (of_property_read_u16(np, "fsl,hmask", &uhdlc_priv->hmask))
@@ -1159,7 +1206,7 @@ static int ucc_hdlc_probe(struct platform_device *pdev)
ret = uhdlc_init(uhdlc_priv);
if (ret) {
dev_err(&pdev->dev, "Failed to init uhdlc\n");
- goto free_utdm;
+ goto undo_uhdlc_init;
}
dev = alloc_hdlcdev(uhdlc_priv);
@@ -1188,6 +1235,9 @@ static int ucc_hdlc_probe(struct platform_device *pdev)
free_dev:
free_netdev(dev);
undo_uhdlc_init:
+ iounmap(utdm->siram);
+unmap_si_regs:
+ iounmap(utdm->si_regs);
free_utdm:
if (uhdlc_priv->tsa)
kfree(utdm);
diff --git a/drivers/soc/fsl/qe/qe_tdm.c b/drivers/soc/fsl/qe/qe_tdm.c
index f78c346..76480df 100644
--- a/drivers/soc/fsl/qe/qe_tdm.c
+++ b/drivers/soc/fsl/qe/qe_tdm.c
@@ -44,10 +44,6 @@ int ucc_of_parse_tdm(struct device_node *np, struct ucc_tdm *utdm,
const char *sprop;
int ret = 0;
u32 val;
- struct resource *res;
- struct device_node *np2;
- static int siram_init_flag;
- struct platform_device *pdev;
sprop = of_get_property(np, "fsl,rx-sync-clock", NULL);
if (sprop) {
@@ -124,57 +120,6 @@ int ucc_of_parse_tdm(struct device_node *np, struct ucc_tdm *utdm,
utdm->siram_entry_id = val;
set_si_param(utdm, ut_info);
-
- np2 = of_find_compatible_node(NULL, NULL, "fsl,t1040-qe-si");
- if (!np2)
- return -EINVAL;
-
- pdev = of_find_device_by_node(np2);
- if (!pdev) {
- pr_err("%pOFn: failed to lookup pdev\n", np2);
- of_node_put(np2);
- return -EINVAL;
- }
-
- of_node_put(np2);
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- utdm->si_regs = devm_ioremap_resource(&pdev->dev, res);
- if (IS_ERR(utdm->si_regs)) {
- ret = PTR_ERR(utdm->si_regs);
- goto err_miss_siram_property;
- }
-
- np2 = of_find_compatible_node(NULL, NULL, "fsl,t1040-qe-siram");
- if (!np2) {
- ret = -EINVAL;
- goto err_miss_siram_property;
- }
-
- pdev = of_find_device_by_node(np2);
- if (!pdev) {
- ret = -EINVAL;
- pr_err("%pOFn: failed to lookup pdev\n", np2);
- of_node_put(np2);
- goto err_miss_siram_property;
- }
-
- of_node_put(np2);
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- utdm->siram = devm_ioremap_resource(&pdev->dev, res);
- if (IS_ERR(utdm->siram)) {
- ret = PTR_ERR(utdm->siram);
- goto err_miss_siram_property;
- }
-
- if (siram_init_flag == 0) {
- memset_io(utdm->siram, 0, resource_size(res));
- siram_init_flag = 1;
- }
-
- return ret;
-
-err_miss_siram_property:
- devm_iounmap(&pdev->dev, utdm->si_regs);
return ret;
}
EXPORT_SYMBOL(ucc_of_parse_tdm);
--
2.9.5