This is a note to let you know that I've just added the patch titled e100: fix length calculation in e100_get_regs_len to the 5.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: e100-fix-length-calculation-in-e100_get_regs_len.patch and it can be found in the queue-5.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 7597a16bdad4c9ace8e753903a973948a0ffdf6a Author: Jacob Keller <jacob.e.keller@xxxxxxxxx> Date: Wed Sep 8 10:52:36 2021 -0700 e100: fix length calculation in e100_get_regs_len [ Upstream commit 4329c8dc110b25d5f04ed20c6821bb60deff279f ] 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 <felicitashetzelt@xxxxxxxxx> Signed-off-by: Jacob Keller <jacob.e.keller@xxxxxxxxx> Signed-off-by: Tony Nguyen <anthony.l.nguyen@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ethernet/intel/e100.c b/drivers/net/ethernet/intel/e100.c index 1b0958bd24f6..71b9f0563b32 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,