From: Al Viro Date: Sun, 23 Aug 2020 03:05:44 +0000 (-0400) Subject: untangling ep_call_nested(): take pushing cookie into a helper X-Git-Tag: v5.11-rc1~139^2~22 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=3b1688efa01cd5b5dc99d624e9fac68b6112f35d;p=thirdparty%2Flinux.git untangling ep_call_nested(): take pushing cookie into a helper Signed-off-by: Al Viro --- diff --git a/fs/eventpoll.c b/fs/eventpoll.c index 43aecae0935c4..bd2cc78c47c82 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -424,6 +424,21 @@ static inline void ep_set_busy_poll_napi_id(struct epitem *epi) #endif /* CONFIG_NET_RX_BUSY_POLL */ +static bool ep_push_nested(void *cookie) +{ + int i; + + if (nesting > EP_MAX_NESTS) /* too deep nesting */ + return false; + + for (i = 0; i < nesting; i++) { + if (cookies[i] == cookie) /* loop detected */ + return false; + } + cookies[nesting++] = cookie; + return true; +} + /** * ep_call_nested - Perform a bound (possibly) nested call, by checking * that the recursion limit is not exceeded, and that @@ -440,17 +455,10 @@ static inline void ep_set_busy_poll_napi_id(struct epitem *epi) static int ep_call_nested(int (*nproc)(void *, void *, int), void *priv, void *cookie) { - int error, i; + int error; - if (nesting > EP_MAX_NESTS) /* too deep nesting */ + if (!ep_push_nested(cookie)) return -1; - - for (i = 0; i < nesting; i++) { - if (cookies[i] == cookie) /* loop detected */ - return -1; - } - cookies[nesting++] = cookie; - /* Call the nested function */ error = (*nproc)(priv, cookie, nesting - 1); nesting--;