From c1d8c429e4d2ce85ec5c92cf71cb419baf75c56f Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Tue, 7 May 2024 09:10:41 -0400 Subject: [PATCH] SUNRPC: Fix gss_free_in_token_pages() [ Upstream commit bafa6b4d95d97877baa61883ff90f7e374427fae ] Dan Carpenter says: > Commit 5866efa8cbfb ("SUNRPC: Fix svcauth_gss_proxy_init()") from Oct > 24, 2019 (linux-next), leads to the following Smatch static checker > warning: > > net/sunrpc/auth_gss/svcauth_gss.c:1039 gss_free_in_token_pages() > warn: iterator 'i' not incremented > > net/sunrpc/auth_gss/svcauth_gss.c > 1034 static void gss_free_in_token_pages(struct gssp_in_token *in_token) > 1035 { > 1036 u32 inlen; > 1037 int i; > 1038 > --> 1039 i = 0; > 1040 inlen = in_token->page_len; > 1041 while (inlen) { > 1042 if (in_token->pages[i]) > 1043 put_page(in_token->pages[i]); > ^ > This puts page zero over and over. > > 1044 inlen -= inlen > PAGE_SIZE ? PAGE_SIZE : inlen; > 1045 } > 1046 > 1047 kfree(in_token->pages); > 1048 in_token->pages = NULL; > 1049 } Based on the way that the ->pages[] array is constructed in gss_read_proxy_verf(), we know that once the loop encounters a NULL page pointer, the remaining array elements must also be NULL. Reported-by: Dan Carpenter Suggested-by: Trond Myklebust Fixes: 5866efa8cbfb ("SUNRPC: Fix svcauth_gss_proxy_init()") Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin --- net/sunrpc/auth_gss/svcauth_gss.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c index 18734e70c5dd..708297f33875 100644 --- a/net/sunrpc/auth_gss/svcauth_gss.c +++ b/net/sunrpc/auth_gss/svcauth_gss.c @@ -1043,17 +1043,11 @@ null_verifier: static void gss_free_in_token_pages(struct gssp_in_token *in_token) { - u32 inlen; int i; i = 0; - inlen = in_token->page_len; - while (inlen) { - if (in_token->pages[i]) - put_page(in_token->pages[i]); - inlen -= inlen > PAGE_SIZE ? PAGE_SIZE : inlen; - } - + while (in_token->pages[i]) + put_page(in_token->pages[i++]); kfree(in_token->pages); in_token->pages = NULL; }