diff options
author | Ben Hutchings <bhutchings@solarflare.com> | 2011-07-21 15:25:30 -0700 |
---|---|---|
committer | Jonas ABERG <jonas.aberg@stericsson.com> | 2011-10-28 11:07:15 +0200 |
commit | bfc1b635030ec7fd1845a59b1a9b0cb16ab4dd55 (patch) | |
tree | de9ec43b8ca756134ee5de5a80efe036ae0ea21d | |
parent | 7b2287c0e5bc8899686f5501bc10fc64edfa085f (diff) |
ethtool: Allow zero-length register dumps again
commit 67ae7cf1eeda777f79259c4c6cb17a0bd28dee71 upstream.
Some drivers (ab)use the ethtool_ops::get_regs operation to expose
only a hardware revision ID. Commit
a77f5db361ed9953b5b749353ea2c7fed2bf8d93 ('ethtool: Allocate register
dump buffer with vmalloc()') had the side-effect of breaking these, as
vmalloc() returns a null pointer for size=0 whereas kmalloc() did not.
For backward-compatibility, allow zero-length dumps again.
Reported-by: Kalle Valo <kvalo@qca.qualcomm.com>
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Change-Id: Iac59f6b9d382c1b185492bf92d90eccc9bd16826
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/35607
Tested-by: Per VAHLNE <per.xx.vahlne@stericsson.com>
Reviewed-by: QABUILD
Reviewed-by: Jonas ABERG <jonas.aberg@stericsson.com>
-rw-r--r-- | net/core/ethtool.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/net/core/ethtool.c b/net/core/ethtool.c index fd14116ad7f..4fb77049e83 100644 --- a/net/core/ethtool.c +++ b/net/core/ethtool.c @@ -1227,7 +1227,7 @@ static int ethtool_get_regs(struct net_device *dev, char __user *useraddr) regs.len = reglen; regbuf = vzalloc(reglen); - if (!regbuf) + if (reglen && !regbuf) return -ENOMEM; ops->get_regs(dev, ®s, regbuf); @@ -1236,7 +1236,7 @@ static int ethtool_get_regs(struct net_device *dev, char __user *useraddr) if (copy_to_user(useraddr, ®s, sizeof(regs))) goto out; useraddr += offsetof(struct ethtool_regs, data); - if (copy_to_user(useraddr, regbuf, regs.len)) + if (regbuf && copy_to_user(useraddr, regbuf, regs.len)) goto out; ret = 0; |