diff options
| author | Sungwoo Kim <contact@sung-woo.kim> | 2024-02-20 00:56:30 -0500 |
|---|---|---|
| committer | Aleksandr Nogikh <nogikh@google.com> | 2024-02-21 14:46:23 +0000 |
| commit | 3eb4f0c2a392b15406af944af98065c12634affd (patch) | |
| tree | 9fe575729b92dd5a7522534eced2fd648e9452d8 | |
| parent | 4622e01246e4f835db558e8c3144c7ca6ea767e6 (diff) | |
vm/qemu.go: fix nil-ptr-deref in ctor
os.Stat() may return (nil, err) if it fails to open a file.
So, the code below wrongly validates st as it will be always nil
if err != nil, causing nil pointer dereference in st.Size().
```
if st, err := os.Stat(inst.image); err != nil && st.Size() == 0 {
```
To fix this, this patch allows st.Size() only if err == nil.
| -rw-r--r-- | vm/qemu/qemu.go | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/vm/qemu/qemu.go b/vm/qemu/qemu.go index 9cb7f565b..b3f1ca0bc 100644 --- a/vm/qemu/qemu.go +++ b/vm/qemu/qemu.go @@ -376,7 +376,7 @@ func (pool *Pool) ctor(workdir, sshkey, sshuser string, index int) (vmimpl.Insta sshuser: sshuser, diagnose: make(chan bool, 1), } - if st, err := os.Stat(inst.image); err != nil && st.Size() == 0 { + if st, err := os.Stat(inst.image); err == nil && st.Size() == 0 { // Some kernels may not need an image, however caller may still // want to pass us a fake empty image because the rest of syzkaller // assumes that an image is mandatory. So if the image is empty, we ignore it. |