diff options
author | Serge E. Hallyn <serue@us.ibm.com> | 2009-09-16 16:27:41 -0500 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-10-09 13:47:24 -0700 |
commit | a8ba8bffbe1f3f8b3450d294b9e68d299b158209 (patch) | |
tree | 39d0dda740dd5dd97fece54db16600bffc60bb6f | |
parent | 3d14b518481eb1fa10c6f6ef9efd5f4cc0f84b28 (diff) | |
download | op-kernel-dev-a8ba8bffbe1f3f8b3450d294b9e68d299b158209.zip op-kernel-dev-a8ba8bffbe1f3f8b3450d294b9e68d299b158209.tar.gz |
Staging: p9auth: a few fixes
1. The memory into which we copy 'u1@u2' needs space for u1, @,
u2, and a final \0 which strcat copies in.
2. Strsep changes the value of its first argument. So use a
temporary variable to pass to it, so we pass the original
value to kfree!
3. Allocate an extra char to user_buf, because we need a trailing \0
since we later kstrdup it.
I am about to send out an LTP testcase for this driver, but
in addition the correctness of the hashing can be verified as
follows:
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
int main(int argc, char *argv[])
{
char in[41], out[20];
unsigned int v;
int i, ret;
ret = read(STDIN_FILENO, in, 40);
if (ret != 40)
exit(1);
in[40] = '\0';
for (i = 0; i < 20; i++) {
sscanf(&in[2*i], "%02x", &v);
out[i] = v;
}
write(STDOUT_FILENO, out, 20);
}
as root, to test userid 501 switching to uid 0, choosing
'random' string 'ab':
echo -n "501@0" > plain
openssl sha1 -hmac 'ab' plain |awk '{ print $2 '} > dgst
./unhex < dgst > dgst.u
mknod /dev/caphash 504 0
mknod /dev/capuse 504 1
chmod ugo+w /dev/capuse
cat dgst.u > /dev/caphash
as uid 501,
echo "501@0@ab" > /dev/capuse
id -u # should now show 0.
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
-rw-r--r-- | drivers/staging/p9auth/p9auth.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/drivers/staging/p9auth/p9auth.c b/drivers/staging/p9auth/p9auth.c index 9111dcb..8ccfff7 100644 --- a/drivers/staging/p9auth/p9auth.c +++ b/drivers/staging/p9auth/p9auth.c @@ -183,7 +183,7 @@ static ssize_t cap_write(struct file *filp, const char __user *buf, user_buf_running = NULL; hash_str = NULL; node_ptr = kmalloc(sizeof(struct cap_node), GFP_KERNEL); - user_buf = kzalloc(count, GFP_KERNEL); + user_buf = kzalloc(count+1, GFP_KERNEL); if (!node_ptr || !user_buf) goto out; @@ -207,6 +207,7 @@ static ssize_t cap_write(struct file *filp, const char __user *buf, list_add(&(node_ptr->list), &(dev->head->list)); node_ptr = NULL; } else { + char *tmpu; if (!cap_devices[0].head || list_empty(&(cap_devices[0].head->list))) { retval = -EINVAL; @@ -218,10 +219,10 @@ static ssize_t cap_write(struct file *filp, const char __user *buf, * need to split it and hash 'user1@user2' using 'randomstring' * as the key. */ - user_buf_running = kstrdup(user_buf, GFP_KERNEL); - source_user = strsep(&user_buf_running, "@"); - target_user = strsep(&user_buf_running, "@"); - rand_str = strsep(&user_buf_running, "@"); + tmpu = user_buf_running = kstrdup(user_buf, GFP_KERNEL); + source_user = strsep(&tmpu, "@"); + target_user = strsep(&tmpu, "@"); + rand_str = tmpu; if (!source_user || !target_user || !rand_str) { retval = -EINVAL; goto out; @@ -229,7 +230,8 @@ static ssize_t cap_write(struct file *filp, const char __user *buf, /* hash the string user1@user2 with rand_str as the key */ len = strlen(source_user) + strlen(target_user) + 1; - hash_str = kzalloc(len, GFP_KERNEL); + /* src, @, len, \0 */ + hash_str = kzalloc(len+1, GFP_KERNEL); strcat(hash_str, source_user); strcat(hash_str, "@"); strcat(hash_str, target_user); |