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 5.4-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-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit e9b4c4989a9abcfa0b3c096186f925424b69074e
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 911b3d2a94e1..ea0f97d76964 100644
--- a/drivers/net/ethernet/intel/e100.c
+++ b/drivers/net/ethernet/intel/e100.c
@@ -2439,7 +2439,11 @@ 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,
