lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <20240809090158.3267481-2-stefan.wiehler@nokia.com>
Date: Fri,  9 Aug 2024 11:01:59 +0200
From: Stefan Wiehler <stefan.wiehler@...ia.com>
To: Rob Herring <robh@...nel.org>,
	Saravana Kannan <saravanak@...gle.com>
Cc: devicetree@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Stefan Wiehler <stefan.wiehler@...ia.com>
Subject: [PATCH v3] of/irq: Prevent device address out-of-bounds read in interrupt map walk

When of_irq_parse_raw() is invoked with a device address smaller than
the interrupt parent node (from #address-cells property), KASAN detects
the following out-of-bounds read when populating the initial match table
(dyndbg="func of_irq_parse_* +p"):

  OF: of_irq_parse_one: dev=/soc@...icasso/watchdog, index=0
  OF:  parent=/soc@...ci@...000000000/gpio0@17,0, intsize=2
  OF:  intspec=4
  OF: of_irq_parse_raw: ipar=/soc@...ci@...000000000/gpio0@17,0, size=2
  OF:  -> addrsize=3
  ==================================================================
  BUG: KASAN: slab-out-of-bounds in of_irq_parse_raw+0x2b8/0x8d0
  Read of size 4 at addr ffffff81beca5608 by task bash/764

  CPU: 1 PID: 764 Comm: bash Tainted: G           O       6.1.67-484c613561-nokia_sm_arm64 #1
  Hardware name: Unknown Unknown Product/Unknown Product, BIOS 2023.01-12.24.03-dirty 01/01/2023
  Call trace:
   dump_backtrace+0xdc/0x130
   show_stack+0x1c/0x30
   dump_stack_lvl+0x6c/0x84
   print_report+0x150/0x448
   kasan_report+0x98/0x140
   __asan_load4+0x78/0xa0
   of_irq_parse_raw+0x2b8/0x8d0
   of_irq_parse_one+0x24c/0x270
   parse_interrupts+0xc0/0x120
   of_fwnode_add_links+0x100/0x2d0
   fw_devlink_parse_fwtree+0x64/0xc0
   device_add+0xb38/0xc30
   of_device_add+0x64/0x90
   of_platform_device_create_pdata+0xd0/0x170
   of_platform_bus_create+0x244/0x600
   of_platform_notify+0x1b0/0x254
   blocking_notifier_call_chain+0x9c/0xd0
   __of_changeset_entry_notify+0x1b8/0x230
   __of_changeset_apply_notify+0x54/0xe4
   of_overlay_fdt_apply+0xc04/0xd94
   ...

  The buggy address belongs to the object at ffffff81beca5600
   which belongs to the cache kmalloc-128 of size 128
  The buggy address is located 8 bytes inside of
   128-byte region [ffffff81beca5600, ffffff81beca5680)

  The buggy address belongs to the physical page:
  page:00000000230d3d03 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1beca4
  head:00000000230d3d03 order:1 compound_mapcount:0 compound_pincount:0
  flags: 0x8000000000010200(slab|head|zone=2)
  raw: 8000000000010200 0000000000000000 dead000000000122 ffffff810000c300
  raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000
  page dumped because: kasan: bad access detected

  Memory state around the buggy address:
   ffffff81beca5500: 04 fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
   ffffff81beca5580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
  >ffffff81beca5600: 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                        ^
   ffffff81beca5680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
   ffffff81beca5700: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc
  ==================================================================
  OF:  -> got it !

Prevent the out-of-bounds read by copying the device address into a
buffer of sufficient size.

Signed-off-by: Stefan Wiehler <stefan.wiehler@...ia.com>
---
 drivers/of/irq.c | 51 ++++++++++++++++++++++++++++++------------------
 1 file changed, 32 insertions(+), 19 deletions(-)

diff --git a/drivers/of/irq.c b/drivers/of/irq.c
index c94203ce65bb3..34fe0593036d8 100644
--- a/drivers/of/irq.c
+++ b/drivers/of/irq.c
@@ -151,6 +151,26 @@ const __be32 *of_irq_parse_imap_parent(const __be32 *imap, int len, struct of_ph
 	return imap;
 }
 
+static u32 of_get_address_cells(struct device_node *node)
+{
+	struct device_node *tnode, *old = NULL;
+	const __be32 *tmp;
+
+	/* Look for this #address-cells. We have to implement the old linux
+	 * trick of looking for the parent here as some device-trees rely on it
+	 */
+	old = of_node_get(node);
+	do {
+		tmp = of_get_property(old, "#address-cells", NULL);
+		tnode = of_get_parent(old);
+		of_node_put(old);
+		old = tnode;
+	} while (old && tmp == NULL);
+	of_node_put(old);
+	old = NULL;
+	return (tmp == NULL) ? 2 : be32_to_cpu(*tmp);
+}
+
 /**
  * of_irq_parse_raw - Low level interrupt tree parsing
  * @addr:	address specifier (start of "reg" property of the device) in be32 format
@@ -167,10 +187,10 @@ const __be32 *of_irq_parse_imap_parent(const __be32 *imap, int len, struct of_ph
  */
 int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq)
 {
-	struct device_node *ipar, *tnode, *old = NULL;
+	struct device_node *ipar, *tnode;
 	__be32 initial_match_array[MAX_PHANDLE_ARGS];
 	const __be32 *match_array = initial_match_array;
-	const __be32 *tmp, dummy_imask[] = { [0 ... MAX_PHANDLE_ARGS] = cpu_to_be32(~0) };
+	const __be32 dummy_imask[] = { [0 ... MAX_PHANDLE_ARGS] = cpu_to_be32(~0) };
 	u32 intsize = 1, addrsize;
 	int i, rc = -EINVAL;
 
@@ -201,20 +221,7 @@ int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq)
 	if (out_irq->args_count != intsize)
 		goto fail;
 
-	/* Look for this #address-cells. We have to implement the old linux
-	 * trick of looking for the parent here as some device-trees rely on it
-	 */
-	old = of_node_get(ipar);
-	do {
-		tmp = of_get_property(old, "#address-cells", NULL);
-		tnode = of_get_parent(old);
-		of_node_put(old);
-		old = tnode;
-	} while (old && tmp == NULL);
-	of_node_put(old);
-	old = NULL;
-	addrsize = (tmp == NULL) ? 2 : be32_to_cpu(*tmp);
-
+	addrsize = of_get_address_cells(ipar);
 	pr_debug(" -> addrsize=%d\n", addrsize);
 
 	/* Range check so that the temporary buffer doesn't overflow */
@@ -343,8 +350,9 @@ int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_ar
 {
 	struct device_node *p;
 	const __be32 *addr;
-	u32 intsize;
+	u32 addrsize, intsize;
 	int i, res;
+	__be32 addr_buf[3] = { 0 };
 
 	pr_debug("of_irq_parse_one: dev=%pOF, index=%d\n", device, index);
 
@@ -354,12 +362,17 @@ int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_ar
 
 	/* Get the reg property (if any) */
 	addr = of_get_property(device, "reg", NULL);
+	addrsize = of_get_address_cells(device);
+
+	/* Prevent out-of-bounds read in case of longer interrupt parent address size */
+	if (addr)
+		memcpy(addr_buf, addr, addrsize * sizeof(addrsize));
 
 	/* Try the new-style interrupts-extended first */
 	res = of_parse_phandle_with_args(device, "interrupts-extended",
 					"#interrupt-cells", index, out_irq);
 	if (!res)
-		return of_irq_parse_raw(addr, out_irq);
+		return of_irq_parse_raw(addr_buf, out_irq);
 
 	/* Look for the interrupt parent. */
 	p = of_irq_find_parent(device);
@@ -389,7 +402,7 @@ int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_ar
 
 
 	/* Check if there are any interrupt-map translations to process */
-	res = of_irq_parse_raw(addr, out_irq);
+	res = of_irq_parse_raw(addr_buf, out_irq);
  out:
 	of_node_put(p);
 	return res;
-- 
2.42.0


Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ