staging: p9auth: prevent some oopses and memory leaks
Before all testcases, do:
mknod /dev/caphash c 253 0
mknod /dev/capuse c 253 1
This patch does the following:
1. caphash write of > CAP_NODE_SIZE bytes overruns node_ptr->data
(test: cat /etc/mime.types > /dev/caphash)
2. make sure we don't dereference a NULL cap_devices[0].head
(test: cat serge@root@abab > /dev/capuse)
3. don't let strlen dereference a NULL target_user etc
(test: echo ab > /dev/capuse)
4. Don't leak a bunch of memory in cap_write(). Note that
technically node_ptr is not needed for the capuse write case.
As a result I have a much more extensive patch splitting up
cap_write(), but I thought a smaller patch that is easier to test
and verify would be a better start. To test:
cnt=0
while [ 1 ]; do
echo /etc/mime.types > /dev/capuse
if [ $((cnt%25)) -eq 0 ]; then
head -2 /proc/meminfo
fi
cnt=$((cnt+1))
sleep 0.3
done
Without this patch, it MemFree steadily drops. With the patch,
it does not.
I have *not* tested this driver (with or without these patches)
with factotum or anything - only using the tests described above.
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
1 file changed