From: Stefan Wiehler stefan.wiehler@nokia.com
[ Upstream commit b739dffa5d570b411d4bdf4bb9b8dfd6b7d72305 ]
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@0/picasso/watchdog, index=0 OF: parent=/soc@0/pci@878000000000/gpio0@17,0, intsize=2 OF: intspec=4 OF: of_irq_parse_raw: ipar=/soc@0/pci@878000000000/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@nokia.com Link: https://lore.kernel.org/r/20240812100652.3800963-1-stefan.wiehler@nokia.com Signed-off-by: Rob Herring (Arm) robh@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/of/irq.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/of/irq.c b/drivers/of/irq.c index c94203ce65bb3..8fd63100ba8f0 100644 --- a/drivers/of/irq.c +++ b/drivers/of/irq.c @@ -344,7 +344,8 @@ int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_ar struct device_node *p; const __be32 *addr; u32 intsize; - int i, res; + int i, res, addr_len; + __be32 addr_buf[3] = { 0 };
pr_debug("of_irq_parse_one: dev=%pOF, index=%d\n", device, index);
@@ -353,13 +354,19 @@ int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_ar return of_irq_parse_oldworld(device, index, out_irq);
/* Get the reg property (if any) */ - addr = of_get_property(device, "reg", NULL); + addr = of_get_property(device, "reg", &addr_len); + + /* Prevent out-of-bounds read in case of longer interrupt parent address size */ + if (addr_len > (3 * sizeof(__be32))) + addr_len = 3 * sizeof(__be32); + if (addr) + memcpy(addr_buf, addr, addr_len);
/* 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 +396,7 @@ 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;