[3.19.y-ckt stable] Patch "net: ethernet: davinci_emac: Fix platform_data overwrite" has been added to the 3.19.y-ckt tree

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    net: ethernet: davinci_emac: Fix platform_data overwrite

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.8-ckt20.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

---8<------------------------------------------------------------

>From 11e2133a50bcf22a86cf7da90fc1da7b2a99d5ee Mon Sep 17 00:00:00 2001
From: Neil Armstrong <narmstrong at baylibre.com>
Date: Wed, 20 Apr 2016 10:56:45 +0200
Subject: net: ethernet: davinci_emac: Fix platform_data overwrite

commit 210990b05a1247886539078e857cd038881bb2d6 upstream.

When the DaVinci emac driver is removed and re-probed, the actual
pdev->dev.platform_data is populated with an unwanted valid pointer saved by
the previous davinci_emac_of_get_pdata() call, causing a kernel crash when
calling priv->int_disable() in emac_int_disable().

Unable to handle kernel paging request at virtual address c8622a80
...
[<c0426fb4>] (emac_int_disable) from [<c0427700>] (emac_dev_open+0x290/0x5f8)
[<c0427700>] (emac_dev_open) from [<c04c00ec>] (__dev_open+0xb8/0x120)
[<c04c00ec>] (__dev_open) from [<c04c0370>] (__dev_change_flags+0x88/0x14c)
[<c04c0370>] (__dev_change_flags) from [<c04c044c>] (dev_change_flags+0x18/0x48)
[<c04c044c>] (dev_change_flags) from [<c052bafc>] (devinet_ioctl+0x6b4/0x7ac)
[<c052bafc>] (devinet_ioctl) from [<c04a1428>] (sock_ioctl+0x1d8/0x2c0)
[<c04a1428>] (sock_ioctl) from [<c014f054>] (do_vfs_ioctl+0x41c/0x600)
[<c014f054>] (do_vfs_ioctl) from [<c014f2a4>] (SyS_ioctl+0x6c/0x7c)
[<c014f2a4>] (SyS_ioctl) from [<c000ff60>] (ret_fast_syscall+0x0/0x1c)

Fixes: 42f59967a091 ("net: ethernet: davinci_emac: add OF support")
Cc: Brian Hutchinson <b.hutchman at gmail.com>
Signed-off-by: Neil Armstrong <narmstrong at baylibre.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/net/ethernet/ti/davinci_emac.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/net/ethernet/ti/davinci_emac.c b/drivers/net/ethernet/ti/davinci_emac.c
index ee40f4e..0793ab8 100644
--- a/drivers/net/ethernet/ti/davinci_emac.c
+++ b/drivers/net/ethernet/ti/davinci_emac.c
@@ -1874,8 +1874,6 @@ davinci_emac_of_get_pdata(struct platform_device *pdev, struct emac_priv *priv)
 		pdata->hw_ram_addr = auxdata->hw_ram_addr;
 	}

-	pdev->dev.platform_data = pdata;
-
 	return  pdata;
 }

--
2.7.4