[PATCH AUTOSEL 5.4 21/33] PCI: xgene-msi: Fix race in installing chained irq handler

[PATCH AUTOSEL 5.4 21/33] PCI: xgene-msi: Fix race in installing chained irq handler

[Sasha Levin]

From: Martin Kaiser <martin@kaiser.cx>

[ Upstream commit a93c00e5f975f23592895b7e83f35de2d36b7633 ]

Fix a race where a pending interrupt could be received and the handler
called before the handler's data has been setup, by converting to
irq_set_chained_handler_and_data().

See also 2cf5a03cb29d ("PCI/keystone: Fix race in installing chained IRQ
handler").

Based on the mail discussion, it seems ok to drop the error handling.

Link: https://lore.kernel.org/r/20210115212435.19940-3-martin@kaiser.cx
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/pci/controller/pci-xgene-msi.c | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/drivers/pci/controller/pci-xgene-msi.c b/drivers/pci/controller/pci-xgene-msi.c
index f4c02da84e59..0bfa5065b440 100644
--- a/drivers/pci/controller/pci-xgene-msi.c
+++ b/drivers/pci/controller/pci-xgene-msi.c
@@ -384,13 +384,9 @@ static int xgene_msi_hwirq_alloc(unsigned int cpu)
 		if (!msi_group->gic_irq)
 			continue;
 
-		irq_set_chained_handler(msi_group->gic_irq,
-					xgene_msi_isr);
-		err = irq_set_handler_data(msi_group->gic_irq, msi_group);
-		if (err) {
-			pr_err("failed to register GIC IRQ handler\n");
-			return -EINVAL;
-		}
+		irq_set_chained_handler_and_data(msi_group->gic_irq,
+			xgene_msi_isr, msi_group);
+
 		/*
 		 * Statically allocate MSI GIC IRQs to each CPU core.
 		 * With 8-core X-Gene v1, 2 MSI GIC IRQs are allocated
-- 
2.30.1

[PATCH AUTOSEL 5.4 23/33] PCI: mediatek: Add missing of_node_put() to fix reference leak

[Sasha Levin]

From: Krzysztof Wilczyński <kw@linux.com>

[ Upstream commit 42814c438aac79746d310f413a27d5b0b959c5de ]

The for_each_available_child_of_node helper internally makes use of the
of_get_next_available_child() which performs an of_node_get() on each
iteration when searching for next available child node.

Should an available child node be found, then it would return a device
node pointer with reference count incremented, thus early return from
the middle of the loop requires an explicit of_node_put() to prevent
reference count leak.

To stop the reference leak, explicitly call of_node_put() before
returning after an error occurred.

Link: https://lore.kernel.org/r/20210120184810.3068794-1-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/pci/controller/pcie-mediatek.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c
index 626a7c352dfd..728a59655825 100644
--- a/drivers/pci/controller/pcie-mediatek.c
+++ b/drivers/pci/controller/pcie-mediatek.c
@@ -1063,14 +1063,14 @@ static int mtk_pcie_setup(struct mtk_pcie *pcie)
 		err = of_pci_get_devfn(child);
 		if (err < 0) {
 			dev_err(dev, "failed to parse devfn: %d\n", err);
-			return err;
+			goto error_put_node;
 		}
 
 		slot = PCI_SLOT(err);
 
 		err = mtk_pcie_parse_port(pcie, child, slot);
 		if (err)
-			return err;
+			goto error_put_node;
 	}
 
 	err = mtk_pcie_subsys_powerup(pcie);
@@ -1086,6 +1086,9 @@ static int mtk_pcie_setup(struct mtk_pcie *pcie)
 		mtk_pcie_subsys_powerdown(pcie);
 
 	return 0;
+error_put_node:
+	of_node_put(child);
+	return err;
 }
 
 static int mtk_pcie_probe(struct platform_device *pdev)
-- 
2.30.1

[PATCH AUTOSEL 5.4 26/33] PCI: Fix pci_register_io_range() memory leak

[Sasha Levin]

From: Geert Uytterhoeven <geert+renesas@glider.be>

[ Upstream commit f6bda644fa3a7070621c3bf12cd657f69a42f170 ]

Kmemleak reports:

  unreferenced object 0xc328de40 (size 64):
    comm "kworker/1:1", pid 21, jiffies 4294938212 (age 1484.670s)
    hex dump (first 32 bytes):
      00 00 00 00 00 00 00 00 e0 d8 fc eb 00 00 00 00  ................
      00 00 10 fe 00 00 00 00 00 00 00 00 00 00 00 00  ................

  backtrace:
    [<ad758d10>] pci_register_io_range+0x3c/0x80
    [<2c7f139e>] of_pci_range_to_resource+0x48/0xc0
    [<f079ecc8>] devm_of_pci_get_host_bridge_resources.constprop.0+0x2ac/0x3ac
    [<e999753b>] devm_of_pci_bridge_init+0x60/0x1b8
    [<a895b229>] devm_pci_alloc_host_bridge+0x54/0x64
    [<e451ddb0>] rcar_pcie_probe+0x2c/0x644

In case a PCI host driver's probe is deferred, the same I/O range may be
allocated again, and be ignored, causing a memory leak.

Fix this by (a) letting logic_pio_register_range() return -EEXIST if the
passed range already exists, so pci_register_io_range() will free it, and
by (b) making pci_register_io_range() not consider -EEXIST an error
condition.

Link: https://lore.kernel.org/r/20210202100332.829047-1-geert+renesas@glider.be
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/pci/pci.c | 4 ++++
 lib/logic_pio.c   | 3 +++
 2 files changed, 7 insertions(+)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 89dece8a4132..ff4e2a9ad8dd 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -3896,6 +3896,10 @@ int pci_register_io_range(struct fwnode_handle *fwnode, phys_addr_t addr,
 	ret = logic_pio_register_range(range);
 	if (ret)
 		kfree(range);
+
+	/* Ignore duplicates due to deferred probing */
+	if (ret == -EEXIST)
+		ret = 0;
 #endif
 
 	return ret;
diff --git a/lib/logic_pio.c b/lib/logic_pio.c
index 905027574e5d..774bb02fff10 100644
--- a/lib/logic_pio.c
+++ b/lib/logic_pio.c
@@ -27,6 +27,8 @@ static DEFINE_MUTEX(io_range_mutex);
  * @new_range: pointer to the IO range to be registered.
  *
  * Returns 0 on success, the error code in case of failure.
+ * If the range already exists, -EEXIST will be returned, which should be
+ * considered a success.
  *
  * Register a new IO range node in the IO range list.
  */
@@ -49,6 +51,7 @@ int logic_pio_register_range(struct logic_pio_hwaddr *new_range)
 	list_for_each_entry(range, &io_range_list, list) {
 		if (range->fwnode == new_range->fwnode) {
 			/* range already there */
+			ret = -EEXIST;
 			goto end_register;
 		}
 		if (range->flags == LOGIC_PIO_CPU_MMIO &&
-- 
2.30.1