spi_mpc83xx: reject invalid transfer sizes

Error out on transfer length != multiple of bytes per word with -EINVAL.
Fixes a buffer overrun crash if length < bytes per word.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
Acked-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Peter Korsgaard 2008-09-13 02:33:15 -07:00 committed by Linus Torvalds
parent 53604dbe13
commit aa77d96ba9
1 changed files with 11 additions and 2 deletions

View File

@ -312,11 +312,20 @@ static int mpc83xx_spi_bufs(struct spi_device *spi, struct spi_transfer *t)
if (t->bits_per_word)
bits_per_word = t->bits_per_word;
len = t->len;
if (bits_per_word > 8)
if (bits_per_word > 8) {
/* invalid length? */
if (len & 1)
return -EINVAL;
len /= 2;
if (bits_per_word > 16)
}
if (bits_per_word > 16) {
/* invalid length? */
if (len & 1)
return -EINVAL;
len /= 2;
}
mpc83xx_spi->count = len;
INIT_COMPLETION(mpc83xx_spi->done);
/* enable rx ints */