From: Dan Rosenberg Date: Wed, 15 Sep 2010 11:43:12 +0000 (+0000) Subject: drivers/net/cxgb3/cxgb3_main.c: prevent reading uninitialized stack memory X-Git-Tag: v2.6.36-rc5~12^2~5 X-Git-Url: http://bbs.cooldavid.org/git/?p=net-next-2.6.git;a=commitdiff_plain;h=49c37c0334a9b85d30ab3d6b5d1acb05ef2ef6de drivers/net/cxgb3/cxgb3_main.c: prevent reading uninitialized stack memory Fixed formatting (tabs and line breaks). The CHELSIO_GET_QSET_NUM device ioctl allows unprivileged users to read 4 bytes of uninitialized stack memory, because the "addr" member of the ch_reg struct declared on the stack in cxgb_extension_ioctl() is not altered or zeroed before being copied back to the user. This patch takes care of it. Signed-off-by: Dan Rosenberg Signed-off-by: David S. Miller --- diff --git a/drivers/net/cxgb3/cxgb3_main.c b/drivers/net/cxgb3/cxgb3_main.c index ad19585d960..f208712c0b9 100644 --- a/drivers/net/cxgb3/cxgb3_main.c +++ b/drivers/net/cxgb3/cxgb3_main.c @@ -2296,6 +2296,8 @@ static int cxgb_extension_ioctl(struct net_device *dev, void __user *useraddr) case CHELSIO_GET_QSET_NUM:{ struct ch_reg edata; + memset(&edata, 0, sizeof(struct ch_reg)); + edata.cmd = CHELSIO_GET_QSET_NUM; edata.val = pi->nqsets; if (copy_to_user(useraddr, &edata, sizeof(edata)))