diff options
| author | Rong Zhang <rongrong@oss.cipunited.com> | 2026-03-16 01:28:22 +0800 |
|---|---|---|
| committer | Thomas Bogendoerfer <tsbogend@alpha.franken.de> | 2026-04-01 21:49:44 +0200 |
| commit | 35d8945bf9b0c4d9586c7fa9fadeecf2cfc26c23 (patch) | |
| tree | 94ff45332359cc40dc0376bd9909f45066ccb06a | |
| parent | 6de23f81a5e08be8fbf5e8d7e9febc72a5b5f27f (diff) | |
MIPS: Loongson64: env: Check UARTs passed by LEFI cautiously
Some firmware does not set nr_uarts properly and passes empty items.
Iterate at most min(system->nr_uarts, MAX_UARTS) items to prevent
out-of-bounds access, and ignore UARTs with addr 0 silently.
Meanwhile, our DT only works with UPIO_MEM but theoretically firmware
may pass other IO types, so explicitly check against that.
Tested on Loongson-LS3A4000-7A1000-NUC-SE.
Fixes: 3989ed418483 ("MIPS: Loongson64: env: Fixup serial clock-frequency when using LEFI")
Cc: stable@vger.kernel.org
Reviewed-by: Yao Zi <me@ziyao.cc>
Signed-off-by: Rong Zhang <rongrong@oss.cipunited.com>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
| -rw-r--r-- | arch/mips/loongson64/env.c | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/arch/mips/loongson64/env.c b/arch/mips/loongson64/env.c index 11ddf02d6a15..7abcca7ab4ed 100644 --- a/arch/mips/loongson64/env.c +++ b/arch/mips/loongson64/env.c @@ -17,7 +17,9 @@ #include <linux/dma-map-ops.h> #include <linux/export.h> #include <linux/libfdt.h> +#include <linux/minmax.h> #include <linux/pci_ids.h> +#include <linux/serial_core.h> #include <linux/string_choices.h> #include <asm/bootinfo.h> #include <loongson.h> @@ -106,9 +108,23 @@ static void __init lefi_fixup_fdt(struct system_loongson *system) is_loongson64g = (read_c0_prid() & PRID_IMP_MASK) == PRID_IMP_LOONGSON_64G; - for (i = 0; i < system->nr_uarts; i++) { + for (i = 0; i < min(system->nr_uarts, MAX_UARTS); i++) { uartdev = &system->uarts[i]; + /* + * Some firmware does not set nr_uarts properly and passes empty + * items. Ignore them silently. + */ + if (uartdev->uart_base == 0) + continue; + + /* Our DT only works with UPIO_MEM. */ + if (uartdev->iotype != UPIO_MEM) { + pr_warn("Ignore UART 0x%llx with iotype %u passed by firmware\n", + uartdev->uart_base, uartdev->iotype); + continue; + } + ret = lefi_fixup_fdt_serial(fdt_buf, uartdev->uart_base, uartdev->uartclk); /* |