6.12-stable review patch. If anyone has any objections, please let me know.
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From: Alexis Lothoré alexis.lothore@bootlin.com
[ Upstream commit cbefe2ffa7784525ec5d008ba87c7add19ec631a ]
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 maxime.chevallier@bootlin.com Signed-off-by: Alexis Lothoré alexis.lothore@bootlin.com Fixes: 8572aec3d0dc ("net: stmmac: Add basic EST support for XGMAC") Link: https://patch.msgid.link/20250529-stmmac_tstamp_div-v4-2-d73340a794d5@bootli... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/stmicro/stmmac/stmmac_est.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_est.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_est.c index c9693f77e1f61..ac6f2e3a3fcd2 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_est.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_est.c @@ -32,6 +32,11 @@ static int est_configure(struct stmmac_priv *priv, struct stmmac_est *cfg, int i, ret = 0; u32 ctrl;
+ if (!ptp_rate) { + netdev_warn(priv->dev, "Invalid PTP rate"); + return -EINVAL; + } + ret |= est_write(est_addr, EST_BTR_LOW, cfg->btr[0], false); ret |= est_write(est_addr, EST_BTR_HIGH, cfg->btr[1], false); ret |= est_write(est_addr, EST_TER, cfg->ter, false);