From 4329c8dc110b25d5f04ed20c6821bb60deff279f Mon Sep 17 00:00:00 2001 From: Jacob Keller Date: Wed, 8 Sep 2021 10:52:36 -0700 Subject: [Backport 4329c8dc110b] 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 --- src/e100.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/src/e100.c b/src/e100.c index 373eb027b925207fdc70b47e413c4055559a2e2d..588a59546d1237e7afb1e6b9bfcce37ecdf03a1c 100644 --- a/src/e100.c +++ b/src/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, -- 2.31.1