diff options
Diffstat (limited to 'FatPkg')
| -rw-r--r-- | FatPkg/EnhancedFatDxe/Misc.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/FatPkg/EnhancedFatDxe/Misc.c b/FatPkg/EnhancedFatDxe/Misc.c index c035670bf7..af66b1d0e3 100644 --- a/FatPkg/EnhancedFatDxe/Misc.c +++ b/FatPkg/EnhancedFatDxe/Misc.c @@ -132,6 +132,7 @@ FatQueueTask ( {
EFI_STATUS Status;
LIST_ENTRY *Link;
+ LIST_ENTRY *NextLink;
FAT_SUBTASK *Subtask;
//
@@ -149,9 +150,17 @@ FatQueueTask ( EfiReleaseLock (&FatTaskLock);
Status = EFI_SUCCESS;
- for ( Link = GetFirstNode (&Task->Subtasks)
- ; !IsNull (&Task->Subtasks, Link)
- ; Link = GetNextNode (&Task->Subtasks, Link)
+ //
+ // Use NextLink to store the next link of the list, because Link might be remove from the
+ // doubly-linked list and get freed in the end of current loop.
+ //
+ // Also, list operation APIs like IsNull() and GetNextNode() are avoided during the loop, since
+ // they may check the validity of doubly-linked lists by traversing them. These APIs cannot
+ // handle list elements being removed during the traverse.
+ //
+ for ( Link = GetFirstNode (&Task->Subtasks), NextLink = GetNextNode (&Task->Subtasks, Link)
+ ; Link != &Task->Subtasks
+ ; Link = NextLink, NextLink = Link->ForwardLink
) {
Subtask = CR (Link, FAT_SUBTASK, Link, FAT_SUBTASK_SIGNATURE);
if (Subtask->Write) {
|