From: Alexis Lothoré Date: Thu, 29 May 2025 09:07:24 +0000 (+0200) Subject: net: stmmac: make sure that ptp_rate is not 0 before configuring EST X-Git-Tag: v6.6.120~8 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b92ec4a848728460f181def33735605f154d438f;p=thirdparty%2Fkernel%2Fstable.git net: stmmac: make sure that ptp_rate is not 0 before configuring EST commit cbefe2ffa7784525ec5d008ba87c7add19ec631a upstream. If the ptp_rate recorded earlier in the driver happens to be 0, this bogus value will propagate up to EST configuration, where it will trigger a division by 0. Prevent this division by 0 by adding the corresponding check and error code. Suggested-by: Maxime Chevallier Signed-off-by: Alexis Lothoré Fixes: 8572aec3d0dc ("net: stmmac: Add basic EST support for XGMAC") Link: https://patch.msgid.link/20250529-stmmac_tstamp_div-v4-2-d73340a794d5@bootlin.com Signed-off-by: Jakub Kicinski [ The context change is due to the commit c3f3b97238f6 ("net: stmmac: Refactor EST implementation") which is irrelevant to the logic of this patch. ] Signed-off-by: Rahul Sharma Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac5.c b/drivers/net/ethernet/stmicro/stmmac/dwmac5.c index 8fd167501fa0e..0afd4644a985f 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac5.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac5.c @@ -597,6 +597,11 @@ int dwmac5_est_configure(void __iomem *ioaddr, struct stmmac_est *cfg, int i, ret = 0x0; u32 ctrl; + if (!ptp_rate) { + pr_warn("Dwmac5: Invalid PTP rate"); + return -EINVAL; + } + ret |= dwmac5_est_write(ioaddr, BTR_LOW, cfg->btr[0], false); ret |= dwmac5_est_write(ioaddr, BTR_HIGH, cfg->btr[1], false); ret |= dwmac5_est_write(ioaddr, TER, cfg->ter, false); diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c index 0bcb378fa0bc9..aab02328a6130 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c @@ -1537,6 +1537,11 @@ static int dwxgmac3_est_configure(void __iomem *ioaddr, struct stmmac_est *cfg, int i, ret = 0x0; u32 ctrl; + if (!ptp_rate) { + pr_warn("Dwxgmac2: Invalid PTP rate"); + return -EINVAL; + } + ret |= dwxgmac3_est_write(ioaddr, XGMAC_BTR_LOW, cfg->btr[0], false); ret |= dwxgmac3_est_write(ioaddr, XGMAC_BTR_HIGH, cfg->btr[1], false); ret |= dwxgmac3_est_write(ioaddr, XGMAC_TER, cfg->ter, false);