mirrors/Astral
1
0
Fork 0
mirror of https://github.com/Mathewnd/Astral.git synced 2026-10-27 12:48:22 +00:00
Code Issues Packages Projects Releases Wiki Activity

mm: fix NULL deref on vnode inactive

Browse Source 
An oversight on vnode inactivation when the last reference was a dirty
page causes a NULL-deref due to VOP_RELEASE set-NULL behavior.

Use a temporary variable in this case as the backing can still be
accesed by a truncation on vnode inactive.
This commit is contained in:
Matheus
2026-10-07 13:21:52 -03:00
parent e25008b80b
commit d999ab7de2
1 changed files with 3 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files
kernel-src/mm/cache.c
+3 -2
View File
@@ -315,6 +315,7 @@ static int sync_page(page_t *page, bool backing_lock) {
page->flags &= ~PAGE_FLAGS_DIRTY;
RELEASE_LOCK();
int e = 0;
vnode_t *backing = page->backing;
if ((page->flags & PAGE_FLAGS_TRUNCATED) == 0) {
if (backing_lock)
VOP_LOCK(page->backing);
@@ -323,11 +324,11 @@ static int sync_page(page_t *page, bool backing_lock) {
if (backing_lock)
VOP_UNLOCK(page->backing);
VOP_RELEASE(page->backing);
VOP_RELEASE(backing);
} else {
// page got truncated from the file while waiting to be written to disk
// its still holding a reference to the vnode, so release that
VOP_RELEASE(page->backing);
VOP_RELEASE(backing);
}
mm_release_page(mm_get_page_address((page_t *)page));