[PATCH] crypto: testmgr - allocate buffers with __GFP_COMP

From: Eric Biggers
Date: Thu Apr 11 2019 - 15:31:23 EST


From: Eric Biggers <ebiggers@xxxxxxxxxx>

This is needed so that CONFIG_HARDENED_USERCOPY_PAGESPAN=y doesn't
incorrectly report a buffer overflow when the destination of
copy_from_iter() spans the page boundary in the 2-page buffer.

Fixes: 3f47a03df6e8 ("crypto: testmgr - add testvec_config struct and helper functions")
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
---
crypto/testmgr.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index 0f6bfb6ce6a46..3522c0bed2492 100644
--- a/crypto/testmgr.c
+++ b/crypto/testmgr.c
@@ -156,7 +156,8 @@ static int __testmgr_alloc_buf(char *buf[XBUFSIZE], int order)
int i;

for (i = 0; i < XBUFSIZE; i++) {
- buf[i] = (char *)__get_free_pages(GFP_KERNEL, order);
+ buf[i] = (char *)__get_free_pages(GFP_KERNEL | __GFP_COMP,
+ order);
if (!buf[i])
goto err_free_buf;
}
--
2.21.0.392.gf8f6787159e-goog