From: Dan Carpenter Date: Tue, 24 Feb 2015 15:34:01 +0000 (+0300) Subject: sunrpc: integer underflow in rsc_parse() X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=76cb4be993c03bf9ec65a58b13f12c679bb041e4;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git sunrpc: integer underflow in rsc_parse() If we call groups_alloc() with invalid values then it's might lead to memory corruption. For example, with a negative value then we might not allocate enough for sizeof(struct group_info). (We're doing this in the caller for consistency with other callers of groups_alloc(). The other alternative might be to move the check out of all the callers into groups_alloc().) Signed-off-by: Dan Carpenter Reviewed-by: Simo Sorce Signed-off-by: J. Bruce Fields --- diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c index 224a82f24d3c..1095be9c80ab 100644 --- a/net/sunrpc/auth_gss/svcauth_gss.c +++ b/net/sunrpc/auth_gss/svcauth_gss.c @@ -463,6 +463,8 @@ static int rsc_parse(struct cache_detail *cd, /* number of additional gid's */ if (get_int(&mesg, &N)) goto out; + if (N < 0 || N > NGROUPS_MAX) + goto out; status = -ENOMEM; rsci.cred.cr_group_info = groups_alloc(N); if (rsci.cred.cr_group_info == NULL)