Pull coredump updates from Christian Brauner:
"This contains an extension to the coredump socket and a proper rework
of the coredump code.
- This extends the coredump socket to allow the coredump server to
tell the kernel how to process individual coredumps. This allows
for fine-grained coredump management. Userspace can decide to just
let the kernel write out the coredump, or generate the coredump
itself, or just reject it.
* COREDUMP_KERNEL
The kernel will write the coredump data to the socket.
* COREDUMP_USERSPACE
The kernel will not write coredump data but will indicate to the
parent that a coredump has been generated. This is used when
userspace generates its own coredumps.
* COREDUMP_REJECT
The kernel will skip generating a coredump for this task.
* COREDUMP_WAIT
The kernel will prevent the task from exiting until the coredump
server has shutdown the socket connection.
The flexible coredump socket can be enabled by using the "@@"
prefix instead of the single "@" prefix for the regular coredump
socket:
@@/run/systemd/coredump.socket
- Cleanup the coredump code properly while we have to touch it
anyway.
Split out each coredump mode in a separate helper so it's easy to
grasp what is going on and make the code easier to follow. The core
coredump function should now be very trivial to follow"
* tag 'vfs-6.17-rc1.coredump' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (31 commits)
cleanup: add a scoped version of CLASS()
coredump: add coredump_skip() helper
coredump: avoid pointless variable
coredump: order auto cleanup variables at the top
coredump: add coredump_cleanup()
coredump: auto cleanup prepare_creds()
cred: add auto cleanup method
coredump: directly return
coredump: auto cleanup argv
coredump: add coredump_write()
coredump: use a single helper for the socket
coredump: move pipe specific file check into coredump_pipe()
coredump: split pipe coredumping into coredump_pipe()
coredump: move core_pipe_count to global variable
coredump: prepare to simplify exit paths
coredump: split file coredumping into coredump_file()
coredump: rename do_coredump() to vfs_coredump()
selftests/coredump: make sure invalid paths are rejected
coredump: validate socket path in coredump_parse()
coredump: don't allow ".." in coredump socket path
...
The coredump.socket_detect_userspace_client test occasionally fails:
# RUN coredump.socket_detect_userspace_client ...
# stackdump_test.c:500:socket_detect_userspace_client:Expected 0 (0) != WIFEXITED(status) (0)
# socket_detect_userspace_client: Test terminated by assertion
# FAIL coredump.socket_detect_userspace_client
not ok 3 coredump.socket_detect_userspace_client
because there is no guarantee that client's write() happens before server's
close(). The client gets terminated SIGPIPE, and thus the test fails.
Add a read() to server to make sure server's close() doesn't happen before
client's write().
Fixes: 7b6724fe9a ("selftests/coredump: add tests for AF_UNIX coredumps")
Signed-off-by: Nam Cao <namcao@linutronix.de>
Link: https://lore.kernel.org/20250620110252.1640391-1-namcao@linutronix.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
The buffer pointer "line" is not initialized. This pointer is passed to
getline().
It can still work if the stack is zero-initialized, because getline() can
work with a NULL pointer as buffer.
But this is obviously broken. This bug shows up while running the test on a
riscv64 machine.
Fix it by properly initializing the pointer.
Fixes: 15858da535 ("selftests: coredump: Add stackdump test")
Signed-off-by: Nam Cao <namcao@linutronix.de>
Link: https://lore.kernel.org/4fb9b6fb3e0040481bacc258c44b4aab5c4df35d.1744383419.git.namcao@linutronix.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
