From daeba89d43af0fa469d38a4ccdc32fff8ca17c2e Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 31 Mar 2008 17:02:02 -0400 Subject: SUNRPC: don't call flush_dcache_page() with an invalid pointer Fix a problem in _copy_to_pages(), whereby it may call flush_dcache_page() with an invalid pointer due to the fact that 'pgto' gets incremented beyond the end of the page array. Fix is to exit the loop without this unnecessary increment of pgto. Signed-off-by: Trond Myklebust --- net/sunrpc/xdr.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c index 995c3fdc16c..79a55d56cc9 100644 --- a/net/sunrpc/xdr.c +++ b/net/sunrpc/xdr.c @@ -244,7 +244,7 @@ _copy_to_pages(struct page **pages, size_t pgbase, const char *p, size_t len) pgto = pages + (pgbase >> PAGE_CACHE_SHIFT); pgbase &= ~PAGE_CACHE_MASK; - do { + for (;;) { copy = PAGE_CACHE_SIZE - pgbase; if (copy > len) copy = len; @@ -253,6 +253,10 @@ _copy_to_pages(struct page **pages, size_t pgbase, const char *p, size_t len) memcpy(vto + pgbase, p, copy); kunmap_atomic(vto, KM_USER0); + len -= copy; + if (len == 0) + break; + pgbase += copy; if (pgbase == PAGE_CACHE_SIZE) { flush_dcache_page(*pgto); @@ -260,8 +264,7 @@ _copy_to_pages(struct page **pages, size_t pgbase, const char *p, size_t len) pgto++; } p += copy; - - } while ((len -= copy) != 0); + } flush_dcache_page(*pgto); } -- cgit v1.2.3-70-g09d2