From: Krzysztof Wilczyński kw@linux.com
stable inclusion from linux-4.19.198 commit 1b78ad07da08ca15c47af0669d5a4e4f896cbb3c
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[ Upstream commit bdcdaa13ad96f1a530711c29e6d4b8311eff767c ]
"utf16s_to_utf8s(..., buf, PAGE_SIZE)" puts up to PAGE_SIZE bytes into "buf" and returns the number of bytes it actually put there. If it wrote PAGE_SIZE bytes, the newline added by dsm_label_utf16s_to_utf8s() would overrun "buf".
Reduce the size available for utf16s_to_utf8s() to use so there is always space for the newline.
[bhelgaas: reorder patch in series, commit log] Fixes: 6058989bad05 ("PCI: Export ACPI _DSM provided firmware instance number and string name to sysfs") Link: https://lore.kernel.org/r/20210603000112.703037-7-kw@linux.com Reported-by: Joe Perches joe@perches.com Signed-off-by: Krzysztof Wilczyński kw@linux.com Signed-off-by: Bjorn Helgaas bhelgaas@google.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/pci/pci-label.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/pci/pci-label.c b/drivers/pci/pci-label.c index a5910f9428576..9fb4ef568f405 100644 --- a/drivers/pci/pci-label.c +++ b/drivers/pci/pci-label.c @@ -162,7 +162,7 @@ static void dsm_label_utf16s_to_utf8s(union acpi_object *obj, char *buf) len = utf16s_to_utf8s((const wchar_t *)obj->buffer.pointer, obj->buffer.length, UTF16_LITTLE_ENDIAN, - buf, PAGE_SIZE); + buf, PAGE_SIZE - 1); buf[len] = '\n'; }