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 ! Signed-off-by: Stefan Wiehler <stefan.wiehler@xxxxxxxxx> --- - Fixed of_get_address_cells() open brace found by checkpatch --- arch/powerpc/platforms/fsl_uli1575.c | 2 +- drivers/bcma/main.c | 2 +- drivers/of/irq.c | 65 ++++++++++++++++------------ drivers/pci/of.c | 2 +- include/linux/of_irq.h | 3 +- 5 files changed, 42 insertions(+), 32 deletions(-) diff --git a/arch/powerpc/platforms/fsl_uli1575.c b/arch/powerpc/platforms/fsl_uli1575.c index b8d37a9932f1b..8da36f72b7b48 100644 --- a/arch/powerpc/platforms/fsl_uli1575.c +++ b/arch/powerpc/platforms/fsl_uli1575.c @@ -335,7 +335,7 @@ static void hpcd_final_uli5288(struct pci_dev *dev) oirq.args_count = 1; laddr[0] = (hose->first_busno << 16) | (PCI_DEVFN(31, 0) << 8); laddr[1] = laddr[2] = 0; - of_irq_parse_raw(laddr, &oirq); + of_irq_parse_raw(laddr, ARRAY_SIZE(laddr), &oirq); dev->irq = irq_create_of_mapping(&oirq); } diff --git a/drivers/bcma/main.c b/drivers/bcma/main.c index 6b5d34919c72b..57d946305496a 100644 --- a/drivers/bcma/main.c +++ b/drivers/bcma/main.c @@ -175,7 +175,7 @@ static int bcma_of_irq_parse(struct device *parent, out_irq->args[0] = num; laddr[0] = cpu_to_be32(core->addr); - return of_irq_parse_raw(laddr, out_irq); + return of_irq_parse_raw(laddr, ARRAY_SIZE(laddr), out_irq); } static unsigned int bcma_of_get_irq(struct device *parent, diff --git a/drivers/of/irq.c b/drivers/of/irq.c index c94203ce65bb3..78c35f81cde8f 100644 --- a/drivers/of/irq.c +++ b/drivers/of/irq.c @@ -151,9 +151,30 @@ 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 + * @addrsize: address cell size ("#address-cells" property of the device (parent)) * @out_irq: structure of_phandle_args updated by this function * * This function is a low-level interrupt tree walking function. It @@ -165,13 +186,13 @@ const __be32 *of_irq_parse_imap_parent(const __be32 *imap, int len, struct of_ph * * Return: 0 on success and a negative number on error */ -int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq) +int of_irq_parse_raw(const __be32 *addr, u32 addrsize, 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) }; - u32 intsize = 1, addrsize; + const __be32 dummy_imask[] = { [0 ... MAX_PHANDLE_ARGS] = cpu_to_be32(~0) }; + u32 intsize = 1, ipar_addrsize; int i, rc = -EINVAL; #ifdef DEBUG @@ -201,24 +222,11 @@ 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); - - pr_debug(" -> addrsize=%d\n", addrsize); + ipar_addrsize = of_get_address_cells(ipar); + pr_debug(" -> addrsize=%d, ipar_addrsize=%d\n", addrsize, ipar_addrsize); /* Range check so that the temporary buffer doesn't overflow */ - if (WARN_ON(addrsize + intsize > MAX_PHANDLE_ARGS)) { + if (WARN_ON(ipar_addrsize + intsize > MAX_PHANDLE_ARGS)) { rc = -EFAULT; goto fail; } @@ -227,7 +235,7 @@ int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq) for (i = 0; i < addrsize; i++) initial_match_array[i] = addr ? addr[i] : 0; for (i = 0; i < intsize; i++) - initial_match_array[addrsize + i] = cpu_to_be32(out_irq->args[i]); + initial_match_array[ipar_addrsize + i] = cpu_to_be32(out_irq->args[i]); /* Now start the actual "proper" walk of the interrupt tree */ while (ipar != NULL) { @@ -254,7 +262,7 @@ int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq) * interrupt-map parsing does not work without a reg * property when #address-cells != 0 */ - if (addrsize && !addr) { + if (ipar_addrsize && !addr) { pr_debug(" -> no reg passed in when needed !\n"); goto fail; } @@ -274,10 +282,10 @@ int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq) /* Parse interrupt-map */ match = 0; - while (imaplen > (addrsize + intsize + 1)) { + while (imaplen > (ipar_addrsize + intsize + 1)) { /* Compare specifiers */ match = 1; - for (i = 0; i < (addrsize + intsize); i++, imaplen--) + for (i = 0; i < (ipar_addrsize + intsize); i++, imaplen--) match &= !((match_array[i] ^ *imap++) & imask[i]); pr_debug(" -> match=%d (imaplen=%d)\n", match, imaplen); @@ -306,7 +314,7 @@ int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq) newpar = out_irq->np; intsize = out_irq->args_count; - addrsize = (imap - match_array) - intsize; + ipar_addrsize = (imap - match_array) - intsize; if (ipar == newpar) { pr_debug("%pOF interrupt-map entry to self\n", ipar); @@ -343,7 +351,7 @@ 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; pr_debug("of_irq_parse_one: dev=%pOF, index=%d\n", device, index); @@ -354,12 +362,13 @@ 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); /* 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, addrsize, out_irq); /* Look for the interrupt parent. */ p = of_irq_find_parent(device); @@ -389,7 +398,7 @@ 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, addrsize, out_irq); out: of_node_put(p); return res; diff --git a/drivers/pci/of.c b/drivers/pci/of.c index 51e3dd0ea5abe..5d4b2ec5a3b13 100644 --- a/drivers/pci/of.c +++ b/drivers/pci/of.c @@ -506,7 +506,7 @@ static int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args * out_irq->args[0] = pin; laddr[0] = cpu_to_be32((pdev->bus->number << 16) | (pdev->devfn << 8)); laddr[1] = laddr[2] = cpu_to_be32(0); - rc = of_irq_parse_raw(laddr, out_irq); + rc = of_irq_parse_raw(laddr, ARRAY_SIZE(laddr), out_irq); if (rc) goto err; return 0; diff --git a/include/linux/of_irq.h b/include/linux/of_irq.h index d6d3eae2f1452..74268e33d7305 100644 --- a/include/linux/of_irq.h +++ b/include/linux/of_irq.h @@ -32,7 +32,8 @@ static inline int of_irq_parse_oldworld(const struct device_node *device, int in } #endif /* CONFIG_PPC32 && CONFIG_PPC_PMAC */ -extern int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq); +extern int of_irq_parse_raw(const __be32 *addr, u32 addrsize, + struct of_phandle_args *out_irq); extern unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data); extern int of_irq_to_resource(struct device_node *dev, int index, struct resource *r); -- 2.42.0