When a thread is terminated via pthread_exit() while blocked in epoll_wait(),
the file reference taken at the beginning of epoll_wait() is not properly
released, leading to resource leaks.
Problem scenario found during libuv test:
1. Echo server thread is blocked in epoll_wait()
2. Main task sends pthread_kill signal to the server thread
3. Signal handler calls pthread_exit() to terminate the thread
4. epoll_wait() is interrupted before reaching the file_put() call
5. The epoll fd reference count remains elevated
6. epoll_do_close() is never called, leaving fds in internal queues
7. File descriptors leak
Solution:
Register a TLS (Thread Local Storage) cleanup handler using tls_cleanup_push()
at the beginning of epoll_wait() blocking section. This ensures that if the
thread exits abnormally (via pthread_exit, pthread_cancel, etc.), the cleanup
handler (epoll_cleanup) will be called automatically to release the file
reference via file_put().
The cleanup handler is properly paired with tls_cleanup_pop() when epoll_wait()
completes normally, ensuring the handler is only invoked on abnormal exit.
This fix is applied to both epoll_wait() code paths (with and without extended
mode) to ensure consistent behavior.
Impact:
- Prevents epoll fd reference count leaks on thread cancellation
- Ensures proper cleanup even when epoll_wait() is interrupted by pthread_exit
- Critical for multi-threaded applications using signals and thread termination
- Works together with previous fix for teardown/oneshot list cleanup
Signed-off-by: dongjiuzhu1 <dongjiuzhu1@xiaomi.com>
When an epoll fd is closed, the file descriptors in the teardown and
oneshot lists were not being properly dereferenced, leading to fd leaks.
This fix ensures that all fds in the teardown and oneshot lists are
properly released via file_put() during epoll_do_close(), matching the
behavior for fds in the setup list.
Impact:
- Prevents fd leaks when epoll fd is closed
- Ensures proper cleanup of all tracked file descriptors
- Critical for applications using EPOLLONESHOT or fd removal operations
Signed-off-by: dongjiuzhu1 <dongjiuzhu1@xiaomi.com>
This patch is a rework of the NuttX file descriptor implementation. The
goal is two-fold:
1. Improve POSIX compliance. The old implementation tied file description
to inode only, not the file struct. POSIX however dictates otherwise.
2. Fix a bug with descriptor duplication (dup2() and dup3()). There is
an existing race condition with this POSIX API that currently results
in a kernel side crash.
The crash occurs when a partially open / closed file descriptor is
duplicated. The reason for the crash is that even if the descriptor is
closed, the file might still be in use by the kernel (due to e.g. ongoing
write to file). The open file data is changed by file_dup3() and this
causes a crash in the device / drivers themselves as they lose access to
the inode and private data.
The fix is done by separating struct file into file and file descriptor
structs. The file struct can live on even if the descriptor is closed,
fixing the crash. This also fixes the POSIX issue, as two descriptors
can now point to the same file.
Signed-off-by: Ville Juven <ville.juven@unikie.com>
Signed-off-by: dongjiuzhu1 <dongjiuzhu1@xiaomi.com>
Most tools used for compliance and SBOM generation use SPDX identifiers
This change brings us a step closer to an easy SBOM generation.
Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
Summary:
1.Add configuration to allocate memory from the specified section
2.Replace all memory operations (kmm_) in the vfs with
fs_heap_. When FS_HEAPSIZE > 0, memory is requested for the file system by specifying a configured heap location. By default (i.e. FS_HEAPSIZE=0) fs_heap_ is equivalent to kmm_
Signed-off-by: chenrun1 <chenrun1@xiaomi.com>
Summary:
1.Modified the i_crefs from int16_t to atomic_int
2.Modified the i_crefs add, delete, read, and initialize interfaces to atomic operations
The purpose of this change is to avoid deadlock in cross-core scenarios, where A Core blocks B Core’s request for a write operation to A Core when A Core requests a read operation to B Core.
Signed-off-by: chenrun1 <chenrun1@xiaomi.com>
Use private naming to avoid conflicts with user applications
In file included from libuv/src/unix/internal.h:25,
from libuv/src/unix/udp.c:23:
libuv/src/uv-common.h:57: warning: "container_of" redefined
57 | #define container_of(ptr, type, member) \
|
In file included from nuttx/include/nuttx/list.h:47,
from nuttx/include/nuttx/tls.h:40,
from nuttx/include/nuttx/sched.h:48,
from nuttx/include/nuttx/arch.h:87,
from nuttx/include/nuttx/userspace.h:35,
from nuttx/include/nuttx/mm/mm.h:30,
from nuttx/include/nuttx/kmalloc.h:34,
from nuttx/include/nuttx/lib/lib.h:31,
from nuttx/include/stdio.h:35,
from apps/system/libuv/libuv/include/uv.h:59,
from libuv/src/unix/udp.c:22:
nuttx/include/nuttx/nuttx.h:48: note: this is the location of the previous definition
48 | #define container_of(ptr, type, member) \
|
Signed-off-by: chao an <anchao@lixiang.com>
1. fs_epoll: try again when epoll_teardown() return 0
when poll_notify() called larger than twice when epoll_wait() blocked
in the eph->sem, the semcount will be larger than 1 when epoll_wait()
unblocked and will return 0 directly at the next epoll_wait.
So retry to wait the eph->sem again when epoll_teardown return 0.
2. fs_epoll: poll_setup the fd again even this fd got non-expected event
Some poll implementations need call poll_setup again when their internal
states changed (e.g., local socket), so should add the fd to the epoll
teardown list and poll_setup again at the next epoll_wait even this fd
got the user non-expected event.
Signed-off-by: Bowen Wang <wangbowen6@xiaomi.com>
since mmap may exist in block_operations, but truncate may not,
moving mmap beforee truncate could make three struct more compatible
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
- Add mmap into file_operations and remove it from ioctl definitions.
- Add mm_map structure definitions to support future unmapping
- Modify all drivers to initialize the operations struct accordingly
Signed-off-by: Jukka Laitinen <jukkax@ssrc.tii.ae>
- Add truncate into file_operations
- Move truncate to be common for mountpt_operations and file_operations
- Modify all drivers to initialize the operations struct accordingly
Signed-off-by: Jukka Laitinen <jukkax@ssrc.tii.ae>
1. epoll_ctl(EPOLL_CTL_ADD) support extend the epoll
events dynamicly;
2. enhance the epoll performance by moving some poll setup
and teardown process to the EPOLL_CTL_ADD/DEL/MOD;
Signed-off-by: wangbowen6 <wangbowen6@xiaomi.com>
-#9 0xf7abf899 in __asan::__asan_report_load2 (addr=4072681776) at ../../../../../src/libsanitizer/asan/asan_rtl.cc:117
-#10 0x5693f718 in inode_release (node=0xf2c03124) at inode/fs_inoderelease.c:69
-#11 0x568ea61b in file_close (filep=0xf55fedd0) at vfs/fs_close.c:79
-#12 0x568e7e56 in nx_close (fd=3) at inode/fs_files.c:528
-#13 0x568e7f0e in close (fd=3) at inode/fs_files.c:562
-#14 0x56e76c39 in epoll_close (epfd=3) at vfs/fs_epoll.c:252
-#15 0x56c33829 in sensor_service_delete (ctrl=0x578b8540 <control>) at src/common.c:439
-#16 0x56a0561e in sensor_middle_service_main (argc=1, argv=0xf55de820) at sensor_main.c:118
-#17 0x56878675 in nxtask_startup (entrypt=0x56a054cc <sensor_middle_service_main>, argc=1, argv=0xf55de820) at sched/task_startup.c:70
-#18 0x5684427a in nxtask_start () at task/task_start.c:133
-#19 0xdeadbeef in ?? ()
reason:
epoll_close -> close -> epoll_do_close (free inode)
-> inode_release (reuse inode, crash)
fix:
use the global inode to match the fd which will return to user.
like the g_sock_inode in fs/socket/socket.c
Signed-off-by: ligd <liguiding1@xiaomi.com>
here is the reason:
1.clock_systime_timespec(core function) always exist regardless the setting
2.CLOCK_MONOTONIC is a foundamental clock type required by many places
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
In current implementation, the asynchronous call "epoll_ctl()" unable
to wakeup the thread if pending on "epoll_wait()", the newly
added/delete FD cannot be used in the current waiting list,
this patch uses a reserved file object to wake up pending poll internal,
re-traverse the waiting list when a new event comes.
Signed-off-by: chao.an <anchao@xiaomi.com>