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| author | Ben Hutchings <bhutchings@solarflare.com> | 2011-07-21 15:25:30 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2011-07-21 15:25:30 -0700 |
| commit | 67ae7cf1eeda777f79259c4c6cb17a0bd28dee71 (patch) | |
| tree | 3644c9018a246df166b220b35d6073efa48a385c /net/core/ethtool.c | |
| parent | 1511022c9aabf253253e35730a6a3b945a2a53a9 (diff) | |
| download | linux-stable-67ae7cf1eeda777f79259c4c6cb17a0bd28dee71.tar.gz linux-stable-67ae7cf1eeda777f79259c4c6cb17a0bd28dee71.tar.bz2 linux-stable-67ae7cf1eeda777f79259c4c6cb17a0bd28dee71.zip | |
ethtool: Allow zero-length register dumps again
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>
Cc: stable@kernel.org [2.6.37+]
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/ethtool.c')
| -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 b7c12a63d0ce..6cdba5fc2bed 100644 --- a/net/core/ethtool.c +++ b/net/core/ethtool.c @@ -923,7 +923,7 @@ 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); @@ -932,7 +932,7 @@ 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; |