From d0802dc411f469569a537283b6f3833af47aece9 Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Mon, 30 Mar 2020 14:38:46 -0700 Subject: net: dsa: bcm_sf2: Fix overflow checks Commit f949a12fd697 ("net: dsa: bcm_sf2: fix buffer overflow doing set_rxnfc") tried to fix the some user controlled buffer overflows in bcm_sf2_cfp_rule_set() and bcm_sf2_cfp_rule_del() but the fix was using CFP_NUM_RULES, which while it is correct not to overflow the bitmaps, is not representative of what the device actually supports. Correct that by using bcm_sf2_cfp_rule_size() instead. The latter subtracts the number of rules by 1, so change the checks from greater than or equal to greater than accordingly. Fixes: f949a12fd697 ("net: dsa: bcm_sf2: fix buffer overflow doing set_rxnfc") Signed-off-by: Florian Fainelli Signed-off-by: David S. Miller --- drivers/net/dsa/bcm_sf2_cfp.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) (limited to 'drivers/net') diff --git a/drivers/net/dsa/bcm_sf2_cfp.c b/drivers/net/dsa/bcm_sf2_cfp.c index 1962c8330daa..f9785027c096 100644 --- a/drivers/net/dsa/bcm_sf2_cfp.c +++ b/drivers/net/dsa/bcm_sf2_cfp.c @@ -882,17 +882,14 @@ static int bcm_sf2_cfp_rule_set(struct dsa_switch *ds, int port, fs->m_ext.data[1])) return -EINVAL; - if (fs->location != RX_CLS_LOC_ANY && fs->location >= CFP_NUM_RULES) + if (fs->location != RX_CLS_LOC_ANY && + fs->location > bcm_sf2_cfp_rule_size(priv)) return -EINVAL; if (fs->location != RX_CLS_LOC_ANY && test_bit(fs->location, priv->cfp.used)) return -EBUSY; - if (fs->location != RX_CLS_LOC_ANY && - fs->location > bcm_sf2_cfp_rule_size(priv)) - return -EINVAL; - ret = bcm_sf2_cfp_rule_cmp(priv, port, fs); if (ret == 0) return -EEXIST; @@ -973,7 +970,7 @@ static int bcm_sf2_cfp_rule_del(struct bcm_sf2_priv *priv, int port, u32 loc) struct cfp_rule *rule; int ret; - if (loc >= CFP_NUM_RULES) + if (loc > bcm_sf2_cfp_rule_size(priv)) return -EINVAL; /* Refuse deleting unused rules, and those that are not unique since -- cgit v1.2.3-58-ga151