Commit graph

3465 commits

Author SHA1 Message Date
Tom
72440d90fe Kernel: Fix BlockCondition::unblock return value
BlockCondition::unblock should return true if it unblocked at
least one thread, not if iterating the blockers had been stopped.
This is a regression introduced by 49a76164c.

Fixes #4670
2020-12-31 10:52:58 +01:00
Tom
82c4812730 Kernel: Remove flawed SharedInodeVMObject assertion
This assertion cannot be safely/reliably made in the
~SharedInodeVMObject destructor. The problem is that
Inode::is_shared_vmobject holds a weak reference to the instance
that is being destroyed (ref count 0). Checking the pointer using
WeakPtr::unsafe_ptr will produce nullptr depending on timing in
this case, and WeakPtr::safe_ref will reliably produce a nullptr
as soon as the reference count drops to 0. The only case where
this assertion could succeed is when WeakPtr::unsafe_ptr returned
the pointer because it won the race against revoking it. And
because WeakPtr::safe_ref will always return a nullptr, we cannot
reliably assert this from the ~SharedInodeVMObject destructor.

Fixes #4621
2020-12-31 10:52:45 +01:00
Andreas Kling
1fdd39ff14 Kernel: Sprinkle some lockers in Inode
It did look pretty suspicious the way we were accessing members in some
of these functions without taking the lock first.
2020-12-31 02:10:31 +01:00
Luke
0f66589007 Everywhere: Fix more typos 2020-12-31 01:47:41 +01:00
Tom
22250780ff Kernel: Fix heap expansions deadlock
If a heap expansion is triggered by allocating from e.g. the
RangeAllocator, which may be holding a spin lock, we cannot
immediately allocate another block of backup memory, which could
require the same locks to be acquired. So, defer allocating the
backup memory

Fixes #4675
2020-12-31 01:15:37 +01:00
asynts
7e62ffbc6e AK+Format: Remove TypeErasedFormatParams& from format function. 2020-12-30 20:33:53 +01:00
Luke
865f5ed4f6 Kernel: Prevent sign bit extension when creating a PDPTE
When doing the cast to u64 on the page directory physical address,
the sign bit was being extended. This only beomes an issue when
crossing the 2 GiB boundary. At >= 2 GiB, the physical address
has the sign bit set. For example, 0x80000000.

This set all the reserved bits in the PDPTE, causing a GPF
when loading the PDPT pointer into CR3. The reserved bits are
presumably there to stop you writing out a physical address that
the CPU physically cannot handle, as the size of the reserved bits
is determined by the physical address width of the CPU.

This fixes this by casting to FlatPtr instead. I believe the sign
extension only happens when casting to a bigger type. I'm also using
FlatPtr because it's a pointer we're writing into the PDPTE.
sizeof(FlatPtr) will always be the same size as sizeof(void*).

This also now asserts that the physical address in the PDPTE is
within the max physical address the CPU supports. This is better
than getting a GPF, because CPU::handle_crash tries to do the same
operation that caused the GPF in the first place. That would cause
an infinite loop of GPFs until the stack was exhausted, causing a
triple fault.

As far as I know and tested, I believe we can now use the full 32-bit
physical range without crashing.

Fixes #4584. See that issue for the full debugging story.
2020-12-30 20:33:15 +01:00
Linus Groh
d84b96bddc Kernel: Embed a Metadata notes entry in coredumps 2020-12-30 16:28:27 +01:00
Linus Groh
91332515a6 Kernel: Add sys$set_coredump_metadata() syscall
This can be used by applications to store information (key/value pairs)
likely useful for debugging, which will then be embedded in the coredump.
2020-12-30 16:28:27 +01:00
Linus Groh
6fe6e0a36a Kernel: Embed a ProcessInfo notes entry in coredumps 2020-12-30 15:00:17 +01:00
Tom
49a76164c8 Kernel: Consolidate the various BlockCondition::unblock variants
The unblock_all variant used to ASSERT if a blocker didn't unblock,
but it wasn't clear from the name that it would do that. Because
the BlockCondition already asserts that no blockers are left at
destruction time, it would still catch blockers that haven't been
unblocked for whatever reason.

Fixes #4496
2020-12-30 13:23:17 +01:00
asynts
50d24e4f98 AK: Make binary_search signature more generic. 2020-12-30 02:13:30 +01:00
Tom
c2332780ee Kernel: Fix HPET::update_time to set ticks within the valid range
ticks_this_second must be less than the ticks per second (frequency).
2020-12-30 02:11:06 +01:00
meme
23b23cee5a Build: Support non-i686 toolchains
* Add SERENITY_ARCH option to CMake for selecting the target toolchain
* Port all build scripts but continue to use i686
* Update GitHub Actions cache to include BuildIt.sh
2020-12-29 17:42:04 +01:00
Andreas Kling
af28a8ad11 Kernel: Hold InodeVMObject reference while inspecting it in sys$mmap() 2020-12-29 15:43:35 +01:00
Andreas Kling
b8db585a83 Kernel: Remove unnecessary non-const Inode::shared_vmobject() 2020-12-29 15:43:35 +01:00
Andreas Kling
30dbe9c78a Kernel+LibC: Add a very limited sys$mremap() implementation
This syscall can currently only remap a shared file-backed mapping into
a private file-backed mapping.
2020-12-29 02:20:43 +01:00
Luke
b980782343 Kernel/VM: Make local_offset in PhysicalRegion::find_one_free_page unsigned
An extension to #4613, as I didn't notice that it also happens here.
2020-12-29 02:20:26 +01:00
Luke
eb38fe4a82 Kernel/VM: Make local_offset in PhysicalRegion::free_page_at unsigned
Anything above or equal to the 2 GB mark has the left most bit set
(0x8000...), which was falsely interpreted as negative due to
local_offset being signed.

This makes it unsigned by using FlatPtr. To check for underflow as
was intended, lets use Checked instead.

Fixes #4585
2020-12-29 01:41:16 +01:00
Andreas Kling
43d9fe15f9 Revert "Kernel: Convert read_block method to get a reference instead of pointer"
This reverts commit 092a13211a.

Fixes #4611.
2020-12-29 00:06:52 +01:00
Liav A
72b1998f0d Kernel: Introduce a new partitioning subsystem
The partitioning code was very outdated, and required a full refactor.
The new subsystem removes duplicated code and uses more AK containers.

The most important change is that all implementations of the
PartitionTable class conform to one interface, which made it possible
to remove unnecessary code in the EBRPartitionTable class.

Finding partitions is now done in the StorageManagement singleton,
instead of doing so in init.cpp.

Also, now we don't try to find partitions on demand - the kernel will
try to detect if a StorageDevice is partitioned, and if so, will check
what is the partition table, which could be MBR, GUID or EBR.
Then, it will create DiskPartitionMetadata object for each partition
that is available in the partition table. This object will be used
by the partition enumeration code to create a DiskPartition with the
correct minor number.
2020-12-27 23:07:44 +01:00
Liav A
43d833d94f Kernel: Add DiskPartitionMetadata Class
This class will be used to describe a partition of a StorageDevice,
without creating a DiskPartition object.
2020-12-27 23:07:44 +01:00
Liav A
3a19e18d1e Kernel: Move Partition code files to the Storage folder
This folder is more appropriate for these files.
2020-12-27 23:07:44 +01:00
Liav A
247517cd4a Kernel: Introduce the DevFS
The DevFS along with DevPtsFS give a complete solution for populating
device nodes in /dev. The main purpose of DevFS is to eliminate the
need of device nodes generation when building the system.

Later on, DevFS will assist with exposing disk partition nodes.
2020-12-27 23:07:44 +01:00
Liav A
18e77aa285 Kernel: Add a method to determine the desired permissions of a Device
This method will be used later in DevFS, to set the appropriate
permissions for each device node.
2020-12-27 23:07:44 +01:00
Liav A
092a13211a Kernel: Convert read_block method to get a reference instead of pointer
BlockBasedFileSystem::read_block method should get a reference of
a UserOrKernelBuffer.

If we need to force caching a block, we will call other method to do so.
2020-12-27 23:07:44 +01:00
Nathan Lanza
d1891f67ac
AK: Use direct-list-initialization for Vector::empend() (#4564)
clang trunk with -std=c++20 doesn't seem to properly look for an
aggregate initializer here when the type being constructed is a simple
aggregate (e.g. `struct Thing { int a; int b; };`). This template fails
to compile in a usage added 12/16/2020 in `AK/Trie.h`.

Both forms of initialization are supposed to call the
aggregate-initializers but direct-list-initialization delegating to
aggregate initializers is a new addition in c++20 that might not be
implemented yet.
2020-12-27 23:06:37 +01:00
Brendan Coles
fae2304c67 Kernel: CoreDump::write_program_headers: set NOTE p_memsz to p_filesz 2020-12-27 22:45:25 +01:00
Andreas Kling
ddaedbca87 Kernel: Allow sys$rename() to rename symlinks
Previously, this syscall would try to rename the target of the link,
not the link itself.
2020-12-27 15:38:07 +01:00
Brian Gianforcaro
815d39886f Kernel: Tag more methods and types as [[nodiscard]]
Tag methods at where not obvserving the return value is an obvious error
with [[nodiscard]] to catch potential future bugs.
2020-12-27 11:09:30 +01:00
Tom
f1534ff36e Kernel: Take into account the time keeper's frequency (if no HPET)
The PIT is now also running at a rate of ~250 ticks/second, so rather
than assuming there are 1000 ticks/second we need to query the timer
being used for the actual frequency.

Fixes #4508
2020-12-27 01:17:50 +01:00
Andreas Kling
0e2b7f9c9a Kernel: Remove the per-process icon_id and sys$set_process_icon()
This was a goofy kernel API where you could assign an icon_id (int) to
a process which referred to a global shbuf with a 16x16 icon bitmap
inside it.

Instead of this, programs that want to display a process icon now
retrieve it from the process executable instead.
2020-12-27 01:16:56 +01:00
Andreas Kling
21ccbc2167 Kernel: Expose process executable paths in /proc/all 2020-12-27 01:16:56 +01:00
Andreas Kling
87492e723b Kernel: Lock target process when generating core dump
Dumping core can happen at the end of a profiling run, and in that case
we have to protect the target process and take the lock while iterating
over its region map.

Fixes #4509.
2020-12-27 01:16:56 +01:00
Tom
74fa894994 Kernel: Remove subheap from list before removing memory
When the ExpandableHeap calls the remove_memory function, the
subheap is assumed to be removed and freed entirely. remove_memory
may drop the underlying memory at any time, but it also may cause
further allocation requests. Not removing it from the list before
calling remove_memory could cause a memory allocation in that
subheap while remove_memory is executing. which then causes issues
once the underlying memory is actually freed.
2020-12-26 19:55:01 +01:00
AnotherTest
7b5aa06702 Kernel: Allow 'elevating' unveil permissions if implicitly inherited from '/'
This can happen when an unveil follows another with a path that is a
sub-path of the other one:
```c++
unveil("/home/anon/.config/whoa.ini", "rw");
unveil("/home/anon", "r"); // this would fail, as "/home/anon" inherits
                           // the permissions of "/", which is None.
```
2020-12-26 16:10:04 +01:00
AnotherTest
a9184fcb76 Kernel: Implement unveil() as a prefix-tree
Fixes #4530.
2020-12-26 11:54:54 +01:00
Lenny Maiorani
b2316701a8 Everywhere: void arguments to C functions
Problem:
- C functions with no arguments require a single `void` in the argument list.

Solution:
- Put the `void` in the argument list of functions in C header files.
2020-12-26 10:10:27 +01:00
Sahan Fernando
6b01d1cf14 LibC: Enable compiler warnings for printf format strings 2020-12-26 10:05:50 +01:00
Andreas Kling
1cfdaf96c4 Kernel: Reset the process dumpable flag on successful non-setid exec
Once we've committed to a new memory layout and non-setid credentials,
we can reset the dumpable flag.
2020-12-26 01:31:24 +01:00
Andreas Kling
82f86e35d6 Kernel+LibC: Introduce a "dumpable" flag for processes
This new flag controls two things:
- Whether the kernel will generate core dumps for the process
- Whether the EUID:EGID should own the process's files in /proc

Processes are automatically made non-dumpable when their EUID or EGID is
changed, either via syscalls that specifically modify those ID's, or via
sys$execve(), when a set-uid or set-gid program is executed.

A process can change its own dumpable flag at any time by calling the
new sys$prctl(PR_SET_DUMPABLE) syscall.

Fixes #4504.
2020-12-25 19:35:55 +01:00
Andreas Kling
3c9bd911b8 Kernel: Make /proc/PID directories owned by the EUID:EGID
This is instead of the UID:GID, since that was allowing some very bad
information leaks like spawning "su" as an unprivileged user and having
full /proc access to it.

Work towards #4504.
2020-12-25 19:35:55 +01:00
Andreas Kling
057c1d4798 Kernel: Fix build with E1000_DEBUG 2020-12-25 19:35:55 +01:00
Andreas Kling
ed5c26d698 AK: Remove custom %w format string specifier
This was a non-standard specifier alias for %04x. This patch replaces
all uses of it with new-style formatting functions instead.
2020-12-25 17:05:05 +01:00
Andreas Kling
cb2c8f71f4 AK: Remove custom %b format string specifier
This was a non-standard specifier alias for %02x. This patch replaces
all uses of it with new-style formatting functions instead.
2020-12-25 17:04:28 +01:00
Andreas Kling
89d3b09638 Kernel: Allocate new main thread stack before committing to exec
If the allocation fails (e.g ENOMEM) we want to simply return an error
from sys$execve() and continue executing the current executable.

This patch also moves make_userspace_stack_for_main_thread() out of the
Thread class since it had nothing in particular to do with Thread.
2020-12-25 16:22:01 +01:00
Andreas Kling
2f1712cc29 Kernel: Move ELF auxiliary vector building out of Process class
Process had a couple of members whose only purpose was holding on to
some temporary data while building the auxiliary vector. Remove those
members and move the vector building to a free function in execve.cpp
2020-12-25 15:23:35 +01:00
Andreas Kling
40e9edd798 LibELF: Move AuxiliaryValue into the ELF namespace 2020-12-25 14:48:30 +01:00
Andreas Kling
6c9a6bea1e Kernel+LibELF: Abort ELF executable load sooner when something fails
Make it possible to bail out of ELF::Image::for_each_program_header()
and then do exactly that if something goes wrong during executable
loading in the kernel.

Also make the errors we return slightly more nuanced than just ENOEXEC.
2020-12-25 14:42:42 +01:00
Andreas Kling
791b32e3c6 Kernel: Remove an unnecessary cast in sys$execve() 2020-12-25 14:16:35 +01:00