There is a problem with the current elf loader for risc-v: when a pair of
PCREL_HI20 / LO12 relocations are encountered, it is assumed that these
will follow each other immediately, as follows:
label:
auipc a0, %pcrel_hi(symbol) // R_RISCV_PCREL_HI20
load/store a0, %pcrel_lo(label)(a0) // R_RISCV_PCREL_LO12_I/S
With this assumption, the hi/lo relocations are both done when a hi20
relocation entry is encountered, first to the current instruction (addr)
and to the next instruction (addr + 4).
However, this assumption is wrong. There is nothing in the elf relocation
specification[1] that mandates this. Thus, the hi/lo relocation always
needs to first fixup the hi-part, and when the lo-part is encountered, it
needs to find the corresponding hi relocation entry, via the given "label".
This necessitates (re-)visiting the relocation entries for the current
section as well as looking for "label" in the symbol table.
The NuttX elf loader does not allow such operations to be done in the
machine specific part, so this patch fixes the relocation issue by
introducing an architecture specific cache for the hi20 relocation and
symbol table entries. When a lo12 relocation is encountered, the cache
can be consulted to find the hi20 part.
[1] https://github.com/riscv-non-isa/riscv-elf-psabi-doc/blob/master/riscv-elf.adoc
The task files should consult the "spawn action" and "O_CLOEXEC flags"
to determine further whether the file should be duplicated.
This PR will further optimize file list duplicating to avoid the performance
regression caused by additional file operations.
Signed-off-by: chao an <anchao@xiaomi.com>
VELAPLATFO-18473
refs:
https://man7.org/linux/man-pages/man2/fcntl.2.html
If the FD_CLOEXEC bit is set, the file descriptor will automatically
be closed during a successful execve(2).
(If the execve(2) fails, the file descriptor is left open.)
modify:
1. Ensure that the child task copies all fds of the parent task,
including those with O_CLOEXE.
2. Make sure spawn_file_action is executed under fd with O_CLOEXEC,
otherwise it will fail.
3. When a new task is activated or exec is called, close all fds
with O_CLOEXEC flags.
Signed-off-by: dongjiuzhu1 <dongjiuzhu1@xiaomi.com>
Using up_textheap_memalign to allocate memory if arch support textheap
for loading section.
The default system heap does not support execution permissions,
so up_textheap_memalign allocation is required.
this patch can fix issue about #11043
update esp32 elf config:
remove -CONFIG_ARCH_USE_TEXT_HEAP=y becuase ARCH_CHIP_ESP32 select
ARCH_HAVE_TEXT_HEAP
Signed-off-by: dongjiuzhu1 <dongjiuzhu1@xiaomi.com>
Handle task spawn attributes as task spawn file actions are handled.
Why? This removes the need for sched_lock() when the task is being
spawned. When loading the new task from a file the scheduler can be
locked for a VERY LONG time, in the order of hundreds of milliseconds!
This is unacceptable for real time operation.
Also fixes a latent bug in exec_module, spawn_file_actions is executed
at a bad location; when CONFIG_ARCH_ADDRENV=y actions will point to the
new process's address environment (as it is temporarily instantiated at
that point). Fix this by moving it to after addrenv_restore.
There is a problem when vfork() calls execv() (or execl()) to start a new application:
When the parent thread calls vfork() it receives and gets the pid of the vforked task,
and not the pid of the desired execv'ed application.
see issue #3334
Signed-off-by: yangyalei <yangyalei@xiaomi.com>
The 'filename' parameter comes from user space and cannot be accessed
after calling ret = addrenv_select(binp->addrenv, &binp->oldenv); as
it changes the address environment and 'filename' points to who knows
where. In this case, calling nxtask_init(filename...) will cause a crash.
Solve this by making a local copy before changing address environment IF
argv = NULL. Why ? Because argv[0] contains the process name in this case
and the argument vector is already copied into kernel memory, thus
passing argv[0] to nxtask_init(argv[0]...) is safe.
Fix the problem when vfork() calls execv() (or execl()) to start a new application:
When the parent thread calls vfork() it receives and gets the pid of the vforked task,
and not the pid of the desired execv'ed application.
issue #3334
Signed-off-by: yangyalei <yangyalei@xiaomi.com>
This option enables architecture-specific memory copy for dynamic code loading.
For example, Ambiq has MRAM regions for instruction which can't load by
the memcpy directly.
Signed-off-by: wangjianyu3 <wangjianyu3@xiaomi.com>
Load all sections to LMA not VMA, so the startup code(e.g. start.S) need
relocate .data section to the final address(VMA) and zero .bss section by self.
For example, SiFli and Actions: Background: Device with small sram,
Bootloader run in sram and psram, need boot to Application, with memory overlap
and without XIP. VMA of .data is in "psram" and LMA in "rom", if not enable
`ELF_LOADTO_LMA`, ELF loader will load the section to VMA (will fill bootloader
itself).
Signed-off-by: wangjianyu3 <wangjianyu3@xiaomi.com>
Implement I_SUID/I_SGID feature for binfs in the POSIX compliant way.
If set-user-ID bit is set in the file permissions, then the effective
user ID of process shall be set to UID of the new process image file.
test case:
hello example emulates to set uid and file set-user-ID bit, and call
geteuid and getegid API.
UID = 2000
GID = 3000
MODE = 06555
nsh> ls -l /bin/hello
-r-sr-sr-x 2000 3000 0 hello
nsh> hello
geteuid:2000
getegid:3000
Signed-off-by: fangxinyong <fangxinyong@xiaomi.com>
From posix spec, if set-user-ID bit is set in the file permissions,
then the effective user ID of the new process shall be set to the
user ID of the new process image file.
Let's ignore whether ST_NOSUID is set on the mounted file system.
https://pubs.opengroup.org/onlinepubs/007904875/functions/exec.html
test step:
hello example build as a module and call geteuid and getegid API.
then set file binary set-user-ID bit on the host.
$ chmod +s apps/bin/hello
nsh> mount -t hostfs -o fs=. /data
nsh> ls -l /data/apps/bin/hello
-rwsrwsr-x 1000 1000 9264 /data/apps/bin/hello
nsh> /data/apps/bin/hello
geteuid:1000
getegid:1000
Signed-off-by: fangxinyong <fangxinyong@xiaomi.com>
1. Update all CMakeLists.txt to adapt to new layout
2. Fix cmake build break
3. Update all new file license
4. Fully compatible with current compilation environment(use configure.sh or cmake as you choose)
------------------
How to test
From within nuttx/. Configure:
cmake -B build -DBOARD_CONFIG=sim/nsh -GNinja
cmake -B build -DBOARD_CONFIG=sim:nsh -GNinja
cmake -B build -DBOARD_CONFIG=sabre-6quad/smp -GNinja
cmake -B build -DBOARD_CONFIG=lm3s6965-ek/qemu-flat -GNinja
(or full path in custom board) :
cmake -B build -DBOARD_CONFIG=$PWD/boards/sim/sim/sim/configs/nsh -GNinja
This uses ninja generator (install with sudo apt install ninja-build). To build:
$ cmake --build build
menuconfig:
$ cmake --build build -t menuconfig
--------------------------
2. cmake/build: reformat the cmake style by cmake-format
https://github.com/cheshirekow/cmake_format
$ pip install cmakelang
$ for i in `find -name CMakeLists.txt`;do cmake-format $i -o $i;done
$ for i in `find -name *\.cmake`;do cmake-format $i -o $i;done
Co-authored-by: Matias N <matias@protobits.dev>
Signed-off-by: chao an <anchao@xiaomi.com>
This change allows boards to define an additional kconfig option, which specifies the final link format of application executables.
By selecting `CONFIG_BINFMT_ELF_RELOCATABLE`, and providing an appropriate linker script, applications can be fully linked, removing the need to process relocations.
This is preparation to use kernel stack for everything when the user
process enters the kernel. Now the user stack is in use when the user
process runs a system call, which might not be the safest option.
The following changes make it possible for Nuttx to load binaries in ELF format which are fully linked.
The change does not include the necessary modifications to produce such binaries. In order to build an applicable binary:
- The userspace applications linker script (`gnu-elf.ld`) needs to modified so the data and text section origin's match those setup by the address environment.
- The makefile used, in `apps/import/Make.defs` needs to remove the `-r` LDELFFLAG.
The spawn proxy thread is a special existence in NuttX, usually some developers
spend a lot of time on stack overflow of spawn proxy thread:
https://github.com/apache/nuttx/issues/9046https://github.com/apache/nuttx/pull/9081
In order to avoid similar issues, this PR will remove spawn proxy thread to simplify
the process of task/posix_spawn().
1. Postpone the related processing of spawn file actions until after task_init()
2. Delete the temporary thread of spawn proxy and related global variables
Signed-off-by: chao an <anchao@xiaomi.com>
1. stack_alloc_ptr should be freed in kernel mode
2. replace nxsched_release_tcb() to nxtask_uninit() to remove tcb from inactive list
Signed-off-by: chao an <anchao@xiaomi.com>
Store the old environment in a local context so another temporary address
environment can be selected. This can happen especially when a process
is being loaded (the new process's mappings are temporarily instantiated)
and and interrupt occurs.
Ville Juven