From: Jacob Keller Date: Wed, 8 Sep 2021 17:52:36 +0000 (-0700) Subject: e100: fix length calculation in e100_get_regs_len X-Git-Tag: v5.15-rc4~23^2~17^2~1 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=4329c8dc110b25d5f04ed20c6821bb60deff279f;p=thirdparty%2Flinux.git e100: fix length calculation in e100_get_regs_len commit abf9b902059f ("e100: cleanup unneeded math") tried to simplify e100_get_regs_len and remove a double 'divide and then multiply' calculation that the e100_reg_regs_len function did. This change broke the size calculation entirely as it failed to account for the fact that the numbered registers are actually 4 bytes wide and not 1 byte. This resulted in a significant under allocation of the register buffer used by e100_get_regs. Fix this by properly multiplying the register count by u32 first before adding the size of the dump buffer. Fixes: abf9b902059f ("e100: cleanup unneeded math") Reported-by: Felicitas Hetzelt Signed-off-by: Jacob Keller Signed-off-by: Tony Nguyen --- diff --git a/drivers/net/ethernet/intel/e100.c b/drivers/net/ethernet/intel/e100.c index 373eb027b9252..588a59546d123 100644 --- a/drivers/net/ethernet/intel/e100.c +++ b/drivers/net/ethernet/intel/e100.c @@ -2441,7 +2441,11 @@ static void e100_get_drvinfo(struct net_device *netdev, static int e100_get_regs_len(struct net_device *netdev) { struct nic *nic = netdev_priv(netdev); - return 1 + E100_PHY_REGS + sizeof(nic->mem->dump_buf); + + /* We know the number of registers, and the size of the dump buffer. + * Calculate the total size in bytes. + */ + return (1 + E100_PHY_REGS) * sizeof(u32) + sizeof(nic->mem->dump_buf); } static void e100_get_regs(struct net_device *netdev,