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These would be truncated by functions that expect NUL-terminated strings. Signed-off-by: Demi Marie Obenour --- drivers/xen/xenbus/xenbus_xs.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c index 12e02eb01f5991b31db451cc57037205359b347f..7cb2a22a7698ac40c81add23476594d9f27de8d0 100644 --- a/drivers/xen/xenbus/xenbus_xs.c +++ b/drivers/xen/xenbus/xenbus_xs.c @@ -569,16 +569,20 @@ int xenbus_scanf(struct xenbus_transaction t, const char *dir, const char *node, const char *fmt, ...) { va_list ap; - int ret; + int ret = 0; + unsigned int len; char *val; - val = xenbus_read(t, dir, node, NULL); + val = xenbus_read(t, dir, node, &len); if (IS_ERR(val)) return PTR_ERR(val); + if (strlen(val) != len) + goto bad; va_start(ap, fmt); ret = vsscanf(val, fmt, ap); va_end(ap); +bad: kfree(val); /* Distinctive errno. */ if (ret == 0) @@ -636,15 +640,18 @@ int xenbus_gather(struct xenbus_transaction t, const char *dir, ...) while (ret == 0 && (name = va_arg(ap, char *)) != NULL) { const char *fmt = va_arg(ap, char *); void *result = va_arg(ap, void *); + unsigned len; char *p; - p = xenbus_read(t, dir, name, NULL); + p = xenbus_read(t, dir, name, &len); if (IS_ERR(p)) { ret = PTR_ERR(p); break; } - if (fmt) { - if (sscanf(p, fmt, result) == 0) + if (strlen(p) != len) + ret = -EINVAL; + else if (fmt) { + if (sscanf(p, fmt, result) <= 0) ret = -EINVAL; kfree(p); } else -- Sincerely, Demi Marie Obenour (she/her/hers) Invisible Things Lab