From: Marc-André Lureau <marcandre.lur...@redhat.com>
Add an open/unlink/mmap fallback for system that do not support memfd.
This patch may require additional SELinux policies to work for enforced
systems, but should gracefully fail nonetheless.
Signed-off-by: Marc-André Lureau <marcandre.lur...@redhat.com>
---
util/memfd.c | 22 ++++++++++++++++++++--
1 file changed, 20 insertions(+), 2 deletions(-)
diff --git a/util/memfd.c b/util/memfd.c
index 3168902..970b5b0 100644
--- a/util/memfd.c
+++ b/util/memfd.c
@@ -84,8 +84,26 @@ void *qemu_memfd_alloc(const char *name, size_t size,
unsigned int seals,
return NULL;
}
} else {
- perror("memfd");
- return NULL;
+ const char *tmpdir = getenv("TMPDIR");
+ gchar *fname;
+
+ tmpdir = tmpdir ? tmpdir : "/tmp";
+
+ fname = g_strdup_printf("%s/memfd-XXXXXX", tmpdir);
+ mfd = mkstemp(fname);
+ unlink(fname);
+ g_free(fname);
+
+ if (mfd == -1) {
+ perror("mkstemp");
+ return NULL;
+ }
+
+ if (ftruncate(mfd, size) == -1) {
+ perror("ftruncate");
+ close(mfd);
+ return NULL;
+ }
}
ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, mfd, 0);
--
2.4.3
