[PATCH 4/5] lib/mpi: mpi_read_from_buffer(): sanitize short buffer printk

From: Nicolai Stange
Date: Thu May 26 2016 - 17:20:41 EST

The first two bytes of the input buffer encode its expected length and
mpi_read_from_buffer() prints a console message if the given buffer is too

However, there are some oddities with how this message is printed:
- It is printed at the default loglevel. This is different from the
one used in the case that the first two bytes' value is unsupportedly
large, i.e. KERN_INFO.
- The format specifier '%d' is used for unsigned ints.
- It prints the values of nread and *ret_nread. This is redundant since
the former is always the latter + 1.

Clean this up as follows:
- Use pr_info() rather than printk() with no loglevel.
- Use the format specifiers '%u' in place if '%d'.
- Do not print the redundant 'nread' but the more helpful 'nbytes' value.

Signed-off-by: Nicolai Stange <nicstange@xxxxxxxxx>
lib/mpi/mpicoder.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/mpi/mpicoder.c b/lib/mpi/mpicoder.c
index 869c66c..2f4d039 100644
--- a/lib/mpi/mpicoder.c
+++ b/lib/mpi/mpicoder.c
@@ -99,8 +99,8 @@ MPI mpi_read_from_buffer(const void *xbuffer, unsigned *ret_nread)

nbytes = DIV_ROUND_UP(nbits, 8);
if (nbytes + 2 > *ret_nread) {
- printk("MPI: mpi larger than buffer nread=%d ret_nread=%d\n",
- *ret_nread + 1, *ret_nread);
+ pr_info("MPI: mpi larger than buffer nbytes=%u ret_nread=%u\n",
+ nbytes, *ret_nread);
return ERR_PTR(-EINVAL);