[PATCH] Check vmalloc return value in vpe_open

From: Jesper Juhl
Date: Sat Oct 30 2010 - 12:47:37 EST


Hi,

I noticed that the return value of the
vmalloc() call in arch/mips/kernel/vpe.c::vpe_open() is not checked, so we
potentially store a null pointer in v->pbuffer. As far as I can tell this
will be a problem. However, I don't know the mips code at all, so there
may be something, somewhere where I did not look, that handles this in a
safe manner but I couldn't find it.

To me it looks like we should do what the patch below implements and check
for a null return and then return -ENOMEM in that case. Comments?

Please CC me on replies as I'm not subscribed to linux-mips.


Signed-off-by: Jesper Juhl <jj@xxxxxxxxxxxxx>
---
vpe.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/arch/mips/kernel/vpe.c b/arch/mips/kernel/vpe.c
index 3eb3cde..22b79f6 100644
--- a/arch/mips/kernel/vpe.c
+++ b/arch/mips/kernel/vpe.c
@@ -1092,6 +1092,10 @@ static int vpe_open(struct inode *inode, struct file *filp)

/* this of-course trashes what was there before... */
v->pbuffer = vmalloc(P_SIZE);
+ if (!v->pbuffer) {
+ pr_warning("VPE loader: unable to allocate memory\n");
+ return -ENOMEM;
+ }
v->plen = P_SIZE;
v->load_addr = NULL;
v->len = 0;


--
Jesper Juhl <jj@xxxxxxxxxxxxx> http://www.chaosbits.net/
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