[PATCH -next] pstore: Avoid size casts for 842 compression
From: Kees Cook
Date: Tue Mar 06 2018 - 18:18:31 EST
Instead of casting, make sure we don't end up with giant values and just
perform regular assignments with unsigned int instead of re-cast size_t.
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
fs/pstore/platform.c | 18 ++++++++++++++----
1 file changed, 14 insertions(+), 4 deletions(-)
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index 19aaefeb052f..df54dd87598a 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -452,27 +452,37 @@ static const struct pstore_zbackend backend_lz4hc = {
static int compress_842(const void *in, void *out, size_t inlen, size_t outlen)
{
int ret;
+ unsigned int size;
- ret = sw842_compress(in, inlen, out, (unsigned int *)&outlen, workspace);
+ if (outlen > UINT_MAX)
+ return -EIO;
+ size = outlen;
+
+ ret = sw842_compress(in, inlen, out, &size, workspace);
if (ret) {
pr_err("sw842_compress error; compression failed!\n");
return ret;
}
- return outlen;
+ return size;
}
static int decompress_842(void *in, void *out, size_t inlen, size_t outlen)
{
int ret;
+ unsigned int size;
- ret = sw842_decompress(in, inlen, out, (unsigned int *)&outlen);
+ if (outlen > UINT_MAX)
+ return -EIO;
+ size = outlen;
+
+ ret = sw842_decompress(in, inlen, out, &size);
if (ret) {
pr_err("sw842_decompress error, ret = %d!\n", ret);
return ret;
}
- return outlen;
+ return size;
}
static void allocate_842(void)
--
2.7.4
--
Kees Cook
Pixel Security