On Mon, Jul 30, 2018 at 12:02 PM Tobias Stoeckmann <tobias@xxxxxxxxxxxxxx> wrote: > > Large file system support is activated by default, which means that > on 32 bit systems, off_t is 64 bit in size. > > Using st.st_size or any other 64 bit variable with mmap can lead to > integer truncation and therefore insufficient memory mapping. > > Signed-off-by: Tobias Stoeckmann <tobias@xxxxxxxxxxxxxx> > --- > libkmod/libkmod-file.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/libkmod/libkmod-file.c b/libkmod/libkmod-file.c > index 5eeba6a..86f34c6 100644 > --- a/libkmod/libkmod-file.c > +++ b/libkmod/libkmod-file.c > @@ -255,6 +255,8 @@ static int load_reg(struct kmod_file *file) > return -errno; > > file->size = st.st_size; > + if ((uintmax_t)st.st_size > (uintmax_t)SIZE_MAX) why casting? Lucas De Marchi > + return -EFBIG; > file->memory = mmap(NULL, file->size, PROT_READ, MAP_PRIVATE, > file->fd, 0); > if (file->memory == MAP_FAILED) > -- > 2.13.2 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-modules" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Lucas De Marchi -- To unsubscribe from this list: send the line "unsubscribe linux-modules" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
