Fix memory leak on sys_exec

cykusz-rs/src/arch/x86_64/task/mod.rs

@@ -1,4 +1,3 @@
-use alloc::string::String;
 use alloc::vec::Vec;
 use core::mem::size_of;
 use core::ptr::Unique;
@@ -19,6 +18,7 @@ use crate::arch::raw::segmentation::SegmentSelector;
 use crate::arch::syscall::SyscallFrame;
 use crate::arch::utils::StackHelper;
 use crate::drivers::elf::ElfHeader;
+use crate::kernel::fs::dirent::DirEntryItem;
 use crate::kernel::mm::virt::PageFlags;
 use crate::kernel::mm::{allocate, VirtAddr, PAGE_SIZE};
 use crate::kernel::mm::{Frame, PhysAddr};
@@ -100,6 +100,7 @@ fn prepare_p4<'a>() -> &'a mut P4Table {
 
 #[allow(unused)]
 fn prepare_tls(vm: &VM, p_table: &mut P4Table, tls: &TlsVmInfo) -> VirtAddr {
+    logln!("prepare tls");
     let mmap = vm
         .mmap_vm(
             Some(tls.mmap_addr_hint),
@@ -450,12 +451,14 @@ impl Task {
         hdr: &ElfHeader,
         vm: &VM,
         tls_vm: Option<TlsVmInfo>,
-        path: String,
+        exe: DirEntryItem,
         args: Option<ExeArgs>,
         envs: Option<ExeArgs>,
     ) -> ! {
         logln!("entry point: {}", entry);
 
+        let path = exe.full_path();
+
         let args = args.map(|a| args::Args::new(a));
         let envs = envs.map(|e| args::Args::new(e));
 
@@ -538,9 +541,12 @@ impl Task {
             helper.write(argp.len()); // int argc
         }
 
+        // !!! Prevent memory leaks as we are not running destructors here!
         drop(envp);
         drop(argp);
         drop(tls_vm);
+        drop(path);
+        drop(exe);
 
         logln!("exec user stack: {:#x}", helper.current());
         assert_eq!(helper.current() % 16, 0);

cykusz-rs/src/kernel/fs/dirent.rs

@@ -27,7 +27,10 @@ impl Cacheable<CacheKey> for DirEntry {
         data.parent = None;
     }
 
-    fn notify_used(&self) {}
+    fn notify_used(&self) {
+        let data = self.write();
+        logln!("mark used: {}", data.name);
+    }
 
     fn deallocate(&self, _me: &CacheItem<CacheKey, DirEntry>) {
         logln!("deallocate {}", _me.data.lock().name);

cykusz-rs/src/kernel/fs/ext2/inode.rs

@@ -18,6 +18,7 @@ use crate::kernel::fs::ext2::disk;
 use crate::kernel::fs::ext2::idata::INodeData;
 use crate::kernel::fs::ext2::Ext2Filesystem;
 use crate::kernel::fs::filesystem::Filesystem;
+use crate::kernel::fs::icache;
 use crate::kernel::fs::icache::{INodeItem, INodeItemStruct};
 use crate::kernel::fs::inode::INode;
 use crate::kernel::fs::pcache::{
@@ -153,19 +154,19 @@ impl LockedExt2INode {
         if hl_count > 0 {
             let mut writer = self.d_inode_writer();
 
-            logln_disabled!("dec_hl_count {}", hl_count - 1);
+            logln!("dec_hl_count {}", hl_count - 1);
             writer.dec_hl_count();
 
             if hl_count == 1 {
                 writer.set_deletion_time(crate::kernel::time::unix_timestamp() as u32);
             }
 
-            logln_disabled!("unref {} hl: {}", id, hl_count - 1);
+            logln!("unref {} hl: {}", id, hl_count - 1);
         }
 
         if hl_count == 1 {
             //It's 0 after decrement
-            logln_disabled!("drop from cache {}", id);
+            logln!("drop from cache {}", id);
             self.ext2_fs().drop_from_cache(id);
         }
     }
@@ -683,7 +684,7 @@ impl INode for LockedExt2INode {
     }
 
     fn unlink(&self, name: &str) -> Result<()> {
-        logln_disabled!("unlink started");
+        logln!("unlink started sc");
 
         let fs = self.ext2_fs();
         let _lock = fs.dir_lock();
@@ -708,6 +709,8 @@ impl INode for LockedExt2INode {
             if inode.ftype()? == FileType::Dir {
                 return Err(FsError::NotFile);
             }
+
+            logln!("inode sc: {}", inode.strong_count());
         }
 
         let mut iter = DirEntIter::new(self.self_ref());
@@ -726,6 +729,8 @@ impl INode for LockedExt2INode {
             logln!("{:?}", e);
         }
 
+        icache::cache().print_stats();
+
         Ok(())
     }
 
@@ -1087,6 +1092,6 @@ impl INode for LockedExt2INode {
     }
 
     fn debug(&self) {
-        logln_disabled!("INode debug: {:?}", self.read_debug(32).d_inode());
+        logln!("INode debug: {:?}", self.read().d_inode());
     }
 }

cykusz-rs/src/kernel/fs/ext2/mod.rs

@@ -150,7 +150,7 @@ impl Ext2Filesystem {
     }
 
     pub fn free_inode(&self, inode: &LockedExt2INode) {
-        logln_disabled!("Free inode: {}", inode.read_debug(33).id());
+        logln!("Free inode: {}", inode.read_debug(33).id());
 
         inode.write_debug(17).free_blocks(self);
 

cykusz-rs/src/kernel/syscall/sys.rs

@@ -548,7 +548,7 @@ pub fn sys_unlink(at: u64, path: u64, path_len: u64, flags: u64) -> SyscallResul
 
     let path = Path::new(path_str);
 
-    logln4!("sys_unlink: {}, flags: {}", path.str(), flags);
+    logln!("sys_unlink: {}, flags: {}", path.str(), flags);
 
     let file = get_dir_entry(at, Some(path), LookupMode::None, true)?;
 

cykusz-rs/src/kernel/task/mod.rs

@@ -210,6 +210,9 @@ impl Task {
         self.filetable().close_on_exec();
         self.filetable().debug();
 
+        // !!! Prevent memory leak as we are not running destructors here!
+        drop(vm);
+
         unsafe {
             // EXEC!
             self.arch_task_mut().exec(
@@ -218,7 +221,7 @@ impl Task {
                 &elf_hdr,
                 self.vm(),
                 tls_vm,
-                exe.full_path(),
+                exe,
                 Some(args),
                 envs,
             )
@@ -781,6 +784,6 @@ impl Task {
 
 impl Drop for Task {
     fn drop(&mut self) {
-        logln4!("drop task {}", self.tid());
+        logln!("drop task {}", self.tid());
     }
 }

cykusz-rs/src/kernel/task/vm.rs

@@ -107,6 +107,7 @@ impl MMapedFile {
 
 impl Drop for MMapedFile {
     fn drop(&mut self) {
+        logln!("drop mapped file");
         for (&addr, mapping) in self.active_mappings.iter() {
             let uaddr: UserAddr = addr.into();
 
@@ -932,6 +933,11 @@ impl Default for VM {
     }
 }
 
+impl Drop for VM {
+    fn drop(&mut self) {
+    }
+}
+
 bitflags! {
     pub struct PageFaultReason: usize {
         const PRESENT = 0b1;

disk-scripts/fsck_disk.sh

@@ -5,8 +5,8 @@ set -e
 losetup -D
 losetup -P /dev/loop0 disk.img
 
-fsck.ext2 /dev/loop0p1 -f -v -n
-fsck.ext2 /dev/loop0p2 -f -v -n
-fsck.ext2 /dev/loop0p3 -f -v -n
+fsck.ext2 /dev/loop0p1 -f -v
+fsck.ext2 /dev/loop0p2 -f -v
+fsck.ext2 /dev/loop0p3 -f -v
 
 losetup -D