[PATCH v2] util/memfd: allow allocating 0 bytes

[Elisha Hollander]

Signed-off-by: donno2048 <just4now666...@gmail.com>
---
 util/memfd.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/util/memfd.c b/util/memfd.c
index 8a2e906..e96e5af 100644
--- a/util/memfd.c
+++ b/util/memfd.c @@ -108,7 +108,7 @@ err:
 void *qemu_memfd_alloc(const char *name, size_t size, unsigned int seals,
                        int *fd, Error **errp)
 { - void *ptr;
+ void *ptr = NULL;
     int mfd = qemu_memfd_create(name, size, false, 0, seals, NULL);

     /* some systems have memfd without sealing */
@@ -131,9 +131,11 @@ void *qemu_memfd_alloc(const char *name, size_t size,
unsigned int seals,
         }
     }

- ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, mfd, 0);
- if (ptr == MAP_FAILED) { - goto err;
+ if (size != 0) {
+ ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, mfd, 0); + if
(ptr == MAP_FAILED) {
+ goto err;
+ }
     }

     *fd = mfd;
--
2.30.2