| Message ID | 7448ec710906250613p5fde8b44s24842a32e42dce37@mail.gmail.com |
|---|---|
| State | Superseded, archived |
| Delegated to: | David Miller |
| Headers | show |
Pablo Bitton <pablo.bitton@gmail.com> writes: > Hello all, > > I have attached a small fix for the following problem: > When davinci_emac interface is down, changing MAC address results in > kernel oops, due to NULL pointer dereference. This should go linux-net after a signoff from Sekhar or Chaithrika. > I apologize for not inlining the patch into the message (since GMail > is the only web client I can use, and it does not allow me to inline > it correctly). You can send via Gmail using git-send-email directly. Read this: http://git.or.cz/gitwiki/GitTips#Mail Kevin > Remarks are welcomed. > > Thanks in advance. > > On Thu, Jun 25, 2009 at 11:31 AM, Nori, Sekhar<nsekhar@ti.com> wrote: >> >> Pablo, >> >> Chaithrika's mails to gmail.com are bouncing, so I am replying >> on her behalf. >> >> " >> You are right there is indeed an issue. We looked at other >> drivers and found that this is solved by checking for netif_running >> to be true before going ahead and setting the mac address. Have a >> look at how this is done in tg3.c driver >> >> http://git.kernel.org/?p=linux/kernel/git/khilman/linux-davinci.git;a=blob;f=drivers/net/tg3.c;h=201be425643a6fb7acb8801bbbb718897c9a6431;hb=35265abf67337f57a023ffeae5f4c492e7f8ea24#l6589 >> " >> >> Can you please go ahead and submit a fix for this to netdev >> mailing list and CC linux-davinci ML? >> >> Thanks, >> Sekhar >> >>> -----Original Message----- >>> From: Pablo Bitton [mailto:pablo.bitton@gmail.com] >>> Sent: Wednesday, June 24, 2009 7:13 PM >>> To: Subrahmanya, Chaithrika >>> Subject: A small fix to davinci_emac driver >>> >>> Hello, >>> >>> In drivers/net/davinci_emac.c file, at emac_dev_setmac_addr() function, rxch >>> is NULL when DaVinci EMAC is down (using "ifconfig eth0 down"). >>> >>> So when MAC address is changed using "ifconfig eth0 hw ether >>> 00:11:22:33:44:55", >>> emac_dev_setmac_addr() performs an illegal access to rxch->mac_addr, which >>> causes a kernel oops. >>> >>> In order to fix this situation, the attached patch is applied (I've couldn't >>> inline it correctly into GMail). >>> Remarks are welcomed. >>> >>> Thanks in advance. >> > > From ae9480af26eba3302614ea3d92077a80341cd190 Mon Sep 17 00:00:00 2001 > From: Pablo Bitton <pablo.bitton@gmail.com> > Date: Tue, 23 Jun 2009 15:45:43 +0300 > Subject: [PATCH] davinci_emac: fix kernel oops when changing MAC address while interface is down > > rxch == NULL when DaVinci EMAC is down (using "ifconfig eth0 down"). > So when MAC address is changed using "ifconfig eth0 hw ether 00:11:22:33:44:55", > emac_dev_setmac_addr() performs an illegal access to rxch->mac_addr, which > causes a kernel oops. > > Signed-off-by: Pablo Bitton <pablo.bitton@gmail.com> > --- > drivers/net/davinci_emac.c | 9 +++++++-- > 1 files changed, 7 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/davinci_emac.c b/drivers/net/davinci_emac.c > index cf689a0..cd114d9 100644 > --- a/drivers/net/davinci_emac.c > +++ b/drivers/net/davinci_emac.c > @@ -1823,9 +1823,14 @@ static int emac_dev_setmac_addr(struct net_device *ndev, void *addr) > > /* Store mac addr in priv and rx channel and set it in EMAC hw */ > memcpy(priv->mac_addr, sa->sa_data, ndev->addr_len); > - memcpy(rxch->mac_addr, sa->sa_data, ndev->addr_len); > memcpy(ndev->dev_addr, sa->sa_data, ndev->addr_len); > - emac_setmac(priv, EMAC_DEF_RX_CH, rxch->mac_addr); > + > + /* If the interface is down - rxch is NULL. */ > + /* MAC address is configured only after the interface is enabled. */ > + if (netif_running(ndev)) { > + memcpy(rxch->mac_addr, sa->sa_data, ndev->addr_len); > + emac_setmac(priv, EMAC_DEF_RX_CH, rxch->mac_addr); > + } > > if (netif_msg_drv(priv)) > dev_notice(emac_dev, "DaVinci EMAC: emac_dev_setmac_addr %s\n", > -- > 1.5.4.3 > > _______________________________________________ > Davinci-linux-open-source mailing list > Davinci-linux-open-source@linux.davincidsp.com > http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/davinci_emac.c b/drivers/net/davinci_emac.c index cf689a0..cd114d9 100644 --- a/drivers/net/davinci_emac.c +++ b/drivers/net/davinci_emac.c @@ -1823,9 +1823,14 @@ static int emac_dev_setmac_addr(struct net_device *ndev, void *addr) /* Store mac addr in priv and rx channel and set it in EMAC hw */ memcpy(priv->mac_addr, sa->sa_data, ndev->addr_len); - memcpy(rxch->mac_addr, sa->sa_data, ndev->addr_len); memcpy(ndev->dev_addr, sa->sa_data, ndev->addr_len); - emac_setmac(priv, EMAC_DEF_RX_CH, rxch->mac_addr); + + /* If the interface is down - rxch is NULL. */ + /* MAC address is configured only after the interface is enabled. */ + if (netif_running(ndev)) { + memcpy(rxch->mac_addr, sa->sa_data, ndev->addr_len); + emac_setmac(priv, EMAC_DEF_RX_CH, rxch->mac_addr); + } if (netif_msg_drv(priv)) dev_notice(emac_dev, "DaVinci EMAC: emac_dev_setmac_addr %s\n",