| Message ID | 1550819742-32155-3-git-send-email-wen.yang99@zte.com.cn (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/5] net: dsa: fix a leaked reference by adding a missing of_node_put | expand |
Wen Yang <wen.yang99@zte.com.cn> wrote: > The call to of_find_node_by_phandle returns a node pointer with refcount > incremented thus it must be explicitly decremented after the last > usage. > > Detected by coccinelle with the following warnings: > ./drivers/net/wireless/mediatek/mt76/eeprom.c:58:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 48, but without a corresponding object release within this function. > ./drivers/net/wireless/mediatek/mt76/eeprom.c:61:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 48, but without a corresponding object release within this function. > ./drivers/net/wireless/mediatek/mt76/eeprom.c:67:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 48, but without a corresponding object release within this function. > ./drivers/net/wireless/mediatek/mt76/eeprom.c:70:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 48, but without a corresponding object release within this function. > ./drivers/net/wireless/mediatek/mt76/eeprom.c:72:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 48, but without a corresponding object release within this function. > > Signed-off-by: Wen Yang <wen.yang99@zte.com.cn> > Cc: Felix Fietkau <nbd@nbd.name> > Cc: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com> > Cc: Kalle Valo <kvalo@codeaurora.org> > Cc: "David S. Miller" <davem@davemloft.net> > Cc: Matthias Brugger <matthias.bgg@gmail.com> > Cc: linux-wireless@vger.kernel.org > Cc: netdev@vger.kernel.org > Cc: linux-arm-kernel@lists.infradead.org > Cc: linux-mediatek@lists.infradead.org > Cc: linux-kernel@vger.kernel.org Patch applied to wireless-drivers-next.git, thanks. 34e022d8b780 mt76: fix a leaked reference by adding a missing of_node_put
> @@ -54,22 +54,30 @@ mt76_get_of_eeprom(struct mt76_dev *dev, int len) > part = np->name; > > mtd = get_mtd_device_nm(part); … > + if (retlen < len) { > + ret = -EINVAL; > + goto out_put_node; I find a jump to an immediately following source code place unnecessary. Would you like to delete it? > + } > > - return 0; > +out_put_node: > + of_node_put(np); > + return ret; > #else Can another bit of fine-tuning matter here? https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/drivers/net/wireless/mediatek/mt76/eeprom.c?id=34e022d8b780a03902d82fb3997ba7c7b1f40c81#n73 Regards, Markus
> > @@ -54,22 +54,30 @@ mt76_get_of_eeprom(struct mt76_dev *dev, int len) > > part = np->name; > > > > mtd = get_mtd_device_nm(part); > … > > + if (retlen < len) { > > + ret = -EINVAL; > > + goto out_put_node; > > I find a jump to an immediately following source code place unnecessary. > Would you like to delete it? > > > > + } > > > > - return 0; > > +out_put_node: > > + of_node_put(np); > > + return ret; > > #else > > Can another bit of fine-tuning matter here? > https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/drivers/net/wireless/mediatek/mt76/eeprom.c?id=34e022d8b780a03902d82fb3997ba7c7b1f40c81#n73 > Hi Markus, Thank you for your comments. We may have some different opinions here. Deleting the goto statement may not be good. If the code further up is changed it's easy enough to miss that a goto statement needs to be added here. Better to set ret to zero explicitly, this is the success path after all. --- a/drivers/net/wireless/mediatek/mt76/eeprom.c +++ b/drivers/net/wireless/mediatek/mt76/eeprom.c @@ -75,6 +75,8 @@ mt76_get_of_eeprom(struct mt76_dev *dev, int len) goto out_put_node; } + ret = 0; + out_put_node: of_node_put(np); return ret; -- Regards, Wen
diff --git a/drivers/net/wireless/mediatek/mt76/eeprom.c b/drivers/net/wireless/mediatek/mt76/eeprom.c index 530e559..a1529920d 100644 --- a/drivers/net/wireless/mediatek/mt76/eeprom.c +++ b/drivers/net/wireless/mediatek/mt76/eeprom.c @@ -54,22 +54,30 @@ mt76_get_of_eeprom(struct mt76_dev *dev, int len) part = np->name; mtd = get_mtd_device_nm(part); - if (IS_ERR(mtd)) - return PTR_ERR(mtd); + if (IS_ERR(mtd)) { + ret = PTR_ERR(mtd); + goto out_put_node; + } - if (size <= sizeof(*list)) - return -EINVAL; + if (size <= sizeof(*list)) { + ret = -EINVAL; + goto out_put_node; + } offset = be32_to_cpup(list); ret = mtd_read(mtd, offset, len, &retlen, dev->eeprom.data); put_mtd_device(mtd); if (ret) - return ret; + goto out_put_node; - if (retlen < len) - return -EINVAL; + if (retlen < len) { + ret = -EINVAL; + goto out_put_node; + } - return 0; +out_put_node: + of_node_put(np); + return ret; #else return -ENOENT; #endif
The call to of_find_node_by_phandle returns a node pointer with refcount incremented thus it must be explicitly decremented after the last usage. Detected by coccinelle with the following warnings: ./drivers/net/wireless/mediatek/mt76/eeprom.c:58:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 48, but without a corresponding object release within this function. ./drivers/net/wireless/mediatek/mt76/eeprom.c:61:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 48, but without a corresponding object release within this function. ./drivers/net/wireless/mediatek/mt76/eeprom.c:67:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 48, but without a corresponding object release within this function. ./drivers/net/wireless/mediatek/mt76/eeprom.c:70:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 48, but without a corresponding object release within this function. ./drivers/net/wireless/mediatek/mt76/eeprom.c:72:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 48, but without a corresponding object release within this function. Signed-off-by: Wen Yang <wen.yang99@zte.com.cn> Cc: Felix Fietkau <nbd@nbd.name> Cc: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com> Cc: Kalle Valo <kvalo@codeaurora.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: linux-wireless@vger.kernel.org Cc: netdev@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-mediatek@lists.infradead.org Cc: linux-kernel@vger.kernel.org --- drivers/net/wireless/mediatek/mt76/eeprom.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-)