// SPDX-License-Identifier: GPL-2.0
#include <linux/slab.h>
#include <linux/file.h>
#include <linux/fdtable.h>
#include <linux/freezer.h>
#include <linux/mm.h>
#include <linux/stat.h>
#include <linux/fcntl.h>
#include <linux/swap.h>
#include <linux/ctype.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/pagemap.h>
#include <linux/perf_event.h>
#include <linux/highmem.h>
#include <linux/spinlock.h>
#include <linux/key.h>
#include <linux/personality.h>
#include <linux/binfmts.h>
#include <linux/coredump.h>
#include <linux/sort.h>
#include <linux/sched/coredump.h>
#include <linux/sched/signal.h>
#include <linux/sched/task_stack.h>
#include <linux/utsname.h>
#include <linux/pid_namespace.h>
#include <linux/module.h>
#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/security.h>
#include <linux/syscalls.h>
#include <linux/tsacct_kern.h>
#include <linux/cn_proc.h>
#include <linux/audit.h>
#include <linux/kmod.h>
#include <linux/fsnotify.h>
#include <linux/fs_struct.h>
#include <linux/pipe_fs_i.h>
#include <linux/oom.h>
#include <linux/compat.h>
#include <linux/fs.h>
#include <linux/path.h>
#include <linux/timekeeping.h>
#include <linux/sysctl.h>
#include <linux/elf.h>
#include <linux/pidfs.h>
#include <linux/net.h>
#include <linux/socket.h>
#include <net/af_unix.h>
#include <net/net_namespace.h>
#include <net/sock.h>
#include <uapi/linux/pidfd.h>
#include <uapi/linux/un.h>
#include <uapi/linux/coredump.h>
#include <linux/uaccess.h>
#include <asm/mmu_context.h>
#include <asm/tlb.h>
#include <asm/exec.h>
#include <trace/events/task.h>
#include "internal.h"
#include <trace/events/sched.h>
#define CREATE_TRACE_POINTS
#include <trace/events/coredump.h>
static bool dump_vma_snapshot(struct coredump_params *cprm);
static void free_vma_snapshot(struct coredump_params *cprm);
#define CORE_FILE_NOTE_SIZE_DEFAULT (4*1024*1024)
/* Define a reasonable max cap */
#define CORE_FILE_NOTE_SIZE_MAX (16*1024*1024)
/*
* File descriptor number for the pidfd for the thread-group leader of
* the coredumping task installed into the usermode helper's file
* descriptor table.
*/
#define COREDUMP_PIDFD_NUMBER 3
static int core_uses_pid;
static unsigned int core_pipe_limit;
static unsigned int core_sort_vma;
static char core_pattern[CORENAME_MAX_SIZE] = "core";
static int core_name_size = CORENAME_MAX_SIZE;
unsigned int core_file_note_size_limit = CORE_FILE_NOTE_SIZE_DEFAULT;
static atomic_t core_pipe_count = ATOMIC_INIT(0);
enum coredump_type_t {
COREDUMP_FILE = 1,
COREDUMP_PIPE = 2,
COREDUMP_SOCK = 3,
COREDUMP_SOCK_REQ = 4,
};
struct core_name {
char *corename __counted_by_ptr(size);
int used, size;
unsigned int core_pipe_limit;
bool core_dumped;
enum coredump_type_t core_type;
u64 mask;
};
static int expand_corename(struct core_name *cn, int size)
{
char *corename;
size = kmalloc_size_roundup(size);
corename = krealloc(cn->corename, size, GFP_KERNEL);
if (!corename)
return -ENOMEM;
cn->corename = corename;
cn->size = size;
if (size > core_name_size) /* racy but harmless */
core_name_size = size;
return 0;
}
static __printf(2, 0) int cn_vprintf(struct core_name *cn, const char *fmt,
va_list arg)
{
int free, need;
va_list arg_copy;
again:
free = cn->size - cn->used;
va_copy(arg_copy, arg);
need = vsnprintf(cn->corename + cn->used, free, fmt, arg_copy);
va_end(arg_copy);
if (need < free) {
cn->used += need;
return 0;
}
if (!expand_corename(cn, cn->size + need - free + 1))
goto again;
return -ENOMEM;
}
static __printf(2, 3) int cn_printf(struct core_name *cn, const char *fmt, ...)
{
va_list arg;
int ret;
va_start(arg, fmt);
ret = cn_vprintf(cn, fmt, arg);
va_end(arg);
return ret;
}
static __printf(2, 3)
int cn_esc_printf(struct core_name *cn, const char *fmt, ...)
{
int cur = cn->used;
va_list arg;
int ret;
va_start(arg, fmt);
ret = cn_vprintf(cn, fmt, arg);
va_end(arg);
if (ret == 0) {
/*
* Ensure that this coredump name component can't cause the
* resulting corefile path to consist of a ".." or ".".
*/
if ((cn->used - cur == 1 && cn->corename[cur] == '.') ||
(cn->used - cur == 2 && cn->corename[cur] == '.'
&& cn->corename[cur+1] == '.'))
cn->corename[cur] = '!';
/*
* Empty names are fishy and could be used to create a "//" in a
* corefile name, causing the coredump to happen one directory
* level too high. Enforce that all components of the core
* pattern are at least one character long.
*/
if (cn->used == cur)
ret = cn_printf(cn, "!");
}
for (; cur < cn->used; ++cur) {
if (cn->corename[cur] == '/')
cn->corename[cur] = '!';
}
return ret;
}
static int cn_print_exe_file(struct core_name *cn, bool name_only)
{
struct file *exe_file;
char *pathbuf, *path, *ptr;
int ret;
exe_file = get_mm_exe_file(current->mm);
if (!exe_file)
return cn_esc_printf(cn, "%s (path unknown)", current->comm);
pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
if (!pathbuf) {
ret = -ENOMEM;
goto put_exe_file;
}
path = file_path(exe_file, pathbuf, PATH_MAX);
if (IS_ERR(path)) {
ret = PTR_ERR(path);
goto free_buf;
}
if (name_only) {
ptr = strrchr(path, '/');
if (ptr)
path = ptr + 1;
}
ret = cn_esc_printf(cn, "%s", path);
free_buf:
kfree(pathbuf);
put_exe_file:
fput(exe_file);
return ret;
}
/*
* coredump_parse will inspect the pattern parameter, and output a name
* into corename, which must have space for at least CORENAME_MAX_SIZE
* bytes plus one byte for the zero terminator.
*/
static bool coredump_parse(struct core_name *cn, struct coredump_params *cprm,
size_t **argv, int *argc)
{
const struct cred *cred = current_cred();
const char *pat_ptr = core_pattern;
bool was_space = false;
int pid_in_pattern = 0;
int err = 0;
cn->mask = COREDUMP_KERNEL;
if (core_pipe_limit)
cn->mask |= COREDUMP_WAIT;
cn->used = 0;
cn->corename = NULL;
cn->core_pipe_limit = 0;
cn->core_dumped = false;
if (*pat_ptr == '|')
cn->core_type = COREDUMP_PIPE;
else if (*pat_ptr == '@')
cn->core_type = COREDUMP_SOCK;
else
cn->core_type = COREDUMP_FILE;
if (expand_corename(cn, core_name_size))
return false;
cn->corename[0] = '\0';
switch (cn->core_type) {
case COREDUMP_PIPE: {
int argvs = sizeof(core_pattern) / 2;
(*argv) = kmalloc_objs(**argv, argvs);
if (!(*argv))
return false;
(*argv)[(*argc)++] = 0;
++pat_ptr;
if (!(*pat_ptr))
return false;
break;
}
case COREDUMP_SOCK: {
/* skip the @ */
pat_ptr++;
if (!(*pat_ptr))
return false;
if (*pat_ptr == '@') {
pat_ptr++;
if (!(*pat_ptr))
return false;
cn->core_type = COREDUMP_SOCK_REQ;
}
err = cn_printf(cn, "%s", pat_ptr);
if (err)
return false;
/* Require absolute paths. */
if (cn->corename[0] != '/')
return false;
/*
* Ensure we can uses spaces to indicate additional
* parameters in the future.
*/
if (strchr(cn->corename, ' ')) {
coredump_report_failure("Coredump socket may not %s contain spaces", cn->corename);
return false;
}
/* Must not contain ".." in the path. */
if (name_contains_dotdot(cn->corename)) {
coredump_report_failure("Coredump socket may not %s contain '..' spaces", cn->corename);
return false;
}
if (strlen(cn->corename) >= UNIX_PATH_MAX) {
coredump_report_failure("Coredump socket path %s too long", cn->corename);
return false;
}
/*
* Currently no need to parse any other options.
* Relevant information can be retrieved from the peer
* pidfd retrievable via SO_PEERPIDFD by the receiver or
* via /proc/<pid>, using the SO_PEERPIDFD to guard
* against pid recycling when opening /proc/<pid>.
*/
return true;
}
case COREDUMP_FILE:
break;
default:
WARN_ON_ONCE(true);
return false;
}
/* Repeat as long as we have more pattern to process and more output
space */
while (*pat_ptr) {
/*
* Split on spaces before doing template expansion so that
* %e and %E don't get split if they have spaces in them
*/
if (cn->core_type == COREDUMP_PIPE) {
if (isspace(*pat_ptr)) {
if (cn->used != 0)
was_space = true;
pat_ptr++;
continue;
} else if (was_space) {
was_space = false;
err = cn_printf(cn, "%c", '\0');
if (err)
return false;
(*argv)[(*argc)++] = cn->used;
}
}
if (*pat_ptr != '%') {
err = cn_printf(cn, "%c", *pat_ptr++);
} else {
switch (*++pat_ptr) {
/* single % at the end, drop that */
case 0:
goto out;
/* Double percent, output one percent */
case '%':
err = cn_printf(cn, "%c", '%');
break;
/* pid */
case 'p':
pid_in_pattern = 1;
err = cn_printf(cn, "%d",
task_tgid_vnr(current));
break;
/* global pid */
case 'P':
err = cn_printf(cn, "%d",
task_tgid_nr(current));
break;
case 'i':
err = cn_printf(cn, "%d",
task_pid_vnr(current));
break;
case 'I':
err = cn_printf(cn, "%d",
task_pid_nr(current));
break;
/* uid */
case 'u':
err = cn_printf(cn, "%u",
from_kuid(&init_user_ns,
cred->uid));
break;
/* gid */
case 'g':
err = cn_printf(cn, "%u",
from_kgid(&init_user_ns,
cred->gid));
break;
case 'd':
err = cn_printf(cn, "%d", cprm->dumpable);
break;
/* signal that caused the coredump */
case 's':
err = cn_printf(cn, "%d",
cprm->siginfo->si_signo);
break;
/* UNIX time of coredump */
case 't': {
time64_t time;
time = ktime_get_real_seconds();
err = cn_printf(cn, "%lld", time);
break;
}
/* hostname */
case 'h':
down_read(&uts_sem);
err = cn_esc_printf(cn, "%s",
utsname()->nodename);
up_read(&uts_sem);
break;
/* executable, could be changed by prctl PR_SET_NAME etc */
case 'e':
err = cn_esc_printf(cn, "%s", current->comm);
break;
/* file name of executable */
case 'f':
err = cn_print_exe_file(cn, true);
break;
case 'E':
err = cn_print_exe_file(cn, false);
break;
/* core limit size */
case 'c':
err = cn_printf(cn, "%lu",
rlimit(RLIMIT_CORE));
break;
/* CPU the task ran on */
case 'C':
err = cn_printf(cn, "%d", cprm->cpu);
break;
/* pidfd number */
case 'F': {
/*
* Installing a pidfd only makes sense if
* we actually spawn a usermode helper.
*/
if (cn->core_type != COREDUMP_PIPE)
break;
/*
* Note that we'll install a pidfd for the
* thread-group leader. We know that task
* linkage hasn't been removed yet and even if
* this @current isn't the actual thread-group
* leader we know that the thread-group leader
* cannot be reaped until @current has exited.
*/
cprm->pid = task_tgid(current);
err = cn_printf(cn, "%d", COREDUMP_PIDFD_NUMBER);
break;
}
default:
break;
}
++pat_ptr;
}
if (err)
return false;
}
out:
/* Backward compatibility with core_uses_pid:
*
* If core_pattern does not include a %p (as is the default)
* and core_uses_pid is set, then .%pid will be appended to
* the filename. Do not do this for piped commands. */
if (cn->core_type == COREDUMP_FILE && !pid_in_pattern && core_uses_pid)
return cn_printf(cn, ".%d", task_tgid_vnr(current)) == 0;
return true;
}
static int zap_process(struct signal_struct *signal, int exit_code)
{
struct task_struct *t;
int nr = 0;
signal->flags = SIGNAL_GROUP_EXIT;
signal->group_exit_code = exit_code;
signal->group_stop_count = 0;
__for_each_thread(signal, t) {
task_clear_jobctl_pending(t, JOBCTL_PENDING_MASK);
if (t != current && !(t->flags & PF_POSTCOREDUMP)) {
sigaddset(&t->pending.signal, SIGKILL);
signal_wake_up(t, 1);
nr++;
}
}
return nr;
}
static int zap_threads(struct task_struct *tsk,
struct core_state *core_state, int exit_code)
{
struct signal_struct *signal = tsk->signal;
int nr = -EAGAIN;
spin_lock_irq(&tsk->sighand->siglock);
if (!(signal->flags & SIGNAL_GROUP_EXIT) && !signal->group_exec_task) {
/* Allow SIGKILL, see prepare_signal() */
signal->core_state = core_state;
nr = zap_process(signal, exit_code);
clear_tsk_thread_flag(tsk, TIF_SIGPENDING);
tsk->flags |= PF_DUMPCORE;
atomic_set(&core_state->nr_threads, nr);
}
spin_unlock_irq(&tsk->sighand->siglock);
return nr;
}
static int coredump_wait(int exit_code, struct core_state *core_state)
{
struct task_struct *tsk = current;
int core_waiters = -EBUSY;
init_completion(&core_state->startup);
core_state->dumper.task = tsk;
core_state->dumper.next = NULL;
core_waiters = zap_threads(tsk, core_state, exit_code);
if (core_waiters > 0) {
struct core_thread *ptr;
wait_for_completion_state(&core_state->startup,
TASK_UNINTERRUPTIBLE|TASK_FREEZABLE);
/*
* Wait for all the threads to become inactive, so that
* all the thread context (extended register state, like
* fpu etc) gets copied to the memory.
*/
ptr = core_state->dumper.next;
while (ptr != NULL) {
wait_task_inactive(ptr->task, TASK_ANY);
ptr = ptr->next;
}
}
return core_waiters;
}
static void coredump_finish(bool core_dumped)
{
struct core_thread *curr, *next;
struct task_struct *task;
spin_lock_irq(¤t->sighand->siglock);
if (core_dumped && !__fatal_signal_pending(current))
current->signal->group_exit_code |= 0x80;
next = current->signal->core_state->dumper.next;
current->signal->core_state = NULL;
spin_unlock_irq(¤t->sighand->siglock);
while ((curr = next) != NULL) {
next = curr->next;
task = curr->task;
/*
* see coredump_task_exit(), curr->task must not see
* ->task == NULL before we read ->next.
*/
smp_mb();
curr->task = NULL;
wake_up_process(task);
}
}
static bool dump_interrupted(void)
{
/*
* SIGKILL or freezing() interrupt the coredumping. Perhaps we
* can do try_to_freeze() and check __fatal_signal_pending(),
* but then we need to teach dump_write() to restart and clear
* TIF_SIGPENDING.
*/
return fatal_signal_pending(current) || freezing(current);
}
static void wait_for_dump_helpers(struct file *file)
{
struct pipe_inode_info *pipe = file->private_data;
pipe_lock(pipe);
pipe->readers++;
pipe->writers--;
wake_up_interruptible_sync(&pipe->rd_wait);
kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
pipe_unlock(pipe);
/*
* We actually want wait_event_freezable() but then we need
* to clear TIF_SIGPENDING and improve dump_interrupted().
*/
wait_event_interruptible(pipe->rd_wait, pipe->readers == 1);
pipe_lock(pipe);
pipe->readers--;
pipe->writers++;
pipe_unlock(pipe);
}
/*
* umh_coredump_setup
* helper function to customize the process used
* to collect the core in userspace. Specifically
* it sets up a pipe and installs it as fd 0 (stdin)
* for the process. Returns 0 on success, or
* PTR_ERR on failure.
* Note that it also sets the core limit to 1. This
* is a special value that we use to trap recursive
* core dumps
*/
static int umh_coredump_setup(struct subprocess_info *info, struct cred *new)
{
struct file *files[2];
struct coredump_params *cp = (struct coredump_params *)info->data;
int err;
if (cp->pid) {
struct file *pidfs_file __free(fput) = NULL;
pidfs_file = pidfs_alloc_file(cp->pid, 0);
if (IS_ERR(pidfs_file))
return PTR_ERR(pidfs_file);
pidfs_coredump(cp);
/*
* Usermode helpers are childen of either
* system_dfl_wq or of kthreadd. So we know that
* we're starting off with a clean file descriptor
* table. So we should always be able to use
* COREDUMP_PIDFD_NUMBER as our file descriptor value.
*/
err = replace_fd(COREDUMP_PIDFD_NUMBER, pidfs_file, 0);
if (err < 0)
return err;
}
err = create_pipe_files(files, 0);
if (err)
return err;
cp->file = files[1];
err = replace_fd(0, files[0], 0);
fput(files[0]);
if (err < 0)
return err;
/* and disallow core files too */
current->signal->rlim[RLIMIT_CORE] = (struct rlimit){1, 1};
return 0;
}
#ifdef CONFIG_UNIX
static bool coredump_sock_connect(struct core_name *cn, struct coredump_params *cprm)
{
struct file *file __free(fput) = NULL;
struct sockaddr_un addr = {
.sun_family = AF_UNIX,
};
ssize_t addr_len;
int retval;
struct socket *socket;
addr_len = strscpy(addr.sun_path, cn->corename);
if (addr_len < 0)
return false;
addr_len += offsetof(struct sockaddr_un, sun_path) + 1;
/*
* It is possible that the userspace process which is supposed
* to handle the coredump and is listening on the AF_UNIX socket
* coredumps. Userspace should just mark itself non dumpable.
*/
retval = sock_create_kern(&init_net, AF_UNIX, SOCK_STREAM, 0, &socket);
if (retval < 0)
return false;
file = sock_alloc_file(socket, 0, NULL);
if (IS_ERR(file))
return false;
/*
* Set the thread-group leader pid which is used for the peer
* credentials during connect() below. Then immediately register
* it in pidfs...
*/
cprm->pid = task_tgid(current);
retval = pidfs_register_pid(cprm->pid);
if (retval)
return false;
/*
* ... and set the coredump information so userspace has it
* available after connect()...
*/
pidfs_coredump(cprm);
retval = kernel_connect(socket, (struct sockaddr_unsized *)(&addr), addr_len,
O_NONBLOCK | SOCK_COREDUMP);
if (retval) {
if (retval == -EAGAIN)
coredump_report_failure("Coredump socket %s receive queue full", addr.sun_path);
else
coredump_report_failure("Coredump socket connection %s failed %d", addr.sun_path, retval);
return false;
}
/* ... and validate that @sk_peer_pid matches @cprm.pid. */
if (WARN_ON_ONCE(unix_peer(socket->sk)->sk_peer_pid != cprm->pid))
return false;
cprm->limit = RLIM_INFINITY;
cprm->file = no_free_ptr(file);
return true;
}
static inline bool coredump_sock_recv(struct file *file, struct coredump_ack *ack, size_t size, int flags)
{
struct msghdr msg = {};
struct kvec iov = { .iov_base = ack, .iov_len = size };
ssize_t ret;
memset(ack, 0, size);
ret = kernel_recvmsg(sock_from_file(file), &msg, &iov, 1, size, flags);
return ret == size;
}
static inline bool coredump_sock_send(struct file *file, struct coredump_req *req)
{
struct msghdr msg = { .msg_flags = MSG_NOSIGNAL };
struct kvec iov = { .iov_base = req, .iov_len = sizeof(*req) };
ssize_t ret;
ret = kernel_sendmsg(sock_from_file(file), &msg, &iov, 1, sizeof(*req));
return ret == sizeof(*req);
}
static_assert(sizeof(enum coredump_mark) == sizeof(__u32));
static inline bool coredump_sock_mark(struct file *file, enum coredump_mark mark)
{
struct msghdr msg = { .msg_flags = MSG_NOSIGNAL };
struct kvec iov = { .iov_base = &mark, .iov_len = sizeof(mark) };
ssize_t ret;
ret = kernel_sendmsg(sock_from_file(file), &msg, &iov, 1, sizeof(mark));
return ret == sizeof(mark);
}
static inline void coredump_sock_wait(struct file *file)
{
ssize_t n;
/*
* We use a simple read to wait for the coredump processing to
* finish. Either the socket is closed or we get sent unexpected
* data. In both cases, we're done.
*/
n = __kernel_read(file, &(char){ 0 }, 1, NULL);
if (n > 0)
coredump_report_failure("Coredump socket had unexpected data");
else if (n < 0)
coredump_report_failure("Coredump socket failed");
}
static inline void coredump_sock_shutdown(struct file *file)
{
struct socket *socket;
socket = sock_from_file(file);
if (!socket)
return;
/* Let userspace know we're done processing the coredump. */
kernel_sock_shutdown(socket, SHUT_WR);
}
static bool coredump_sock_request(struct core_name *cn, struct coredump_params *cprm)
{
struct coredump_req req = {
.size = sizeof(struct coredump_req),
.mask = COREDUMP_KERNEL | COREDUMP_USERSPACE |
COREDUMP_REJECT | COREDUMP_WAIT,
.size_ack = sizeof(struct coredump_ack),
};
struct coredump_ack ack = {};
ssize_t usize;
if (cn->core_type != COREDUMP_SOCK_REQ)
return true;
/* Let userspace know what we support. */
if (!coredump_sock_send(cprm->file, &req))
return false;
/* Peek the size of the coredump_ack. */
if (!coredump_sock_recv(cprm->file, &ack, sizeof(ack.size),
MSG_PEEK | MSG_WAITALL))
return false;
/* Refuse unknown coredump_ack sizes. */
usize = ack.size;
if (usize < COREDUMP_ACK_SIZE_VER0) {
coredump_sock_mark(cprm->file, COREDUMP_MARK_MINSIZE);
return false;
}
if (usize > sizeof(ack)) {
coredump_sock_mark(cprm->file, COREDUMP_MARK_MAXSIZE);
return false;
}
/* Now retrieve the coredump_ack. */
if (!coredump_sock_recv(cprm->file, &ack, usize, MSG_WAITALL))
return false;
if (ack.size != usize)
return false;
/* Refuse unknown coredump_ack flags. */
if (ack.mask & ~req.mask) {
coredump_sock_mark(cprm->file, COREDUMP_MARK_UNSUPPORTED);
return false;
}
/* Refuse mutually exclusive options. */
if (hweight64(ack.mask & (COREDUMP_USERSPACE | COREDUMP_KERNEL |
COREDUMP_REJECT)) != 1) {
coredump_sock_mark(cprm->file, COREDUMP_MARK_CONFLICTING);
return false;
}
if (ack.spare) {
coredump_sock_mark(cprm->file, COREDUMP_MARK_UNSUPPORTED);
return false;
}
cn->mask = ack.mask;
return coredump_sock_mark(cprm->file, COREDUMP_MARK_REQACK);
}
static bool coredump_socket(struct core_name *cn, struct coredump_params *cprm)
{
if (!coredump_sock_connect(cn, cprm))
return false;
return coredump_sock_request(cn, cprm);
}
#else
static inline void coredump_sock_wait(struct file *file) { }
static inline void coredump_sock_shutdown(struct file *file) { }
static inline bool coredump_socket(struct core_name *cn, struct coredump_params *cprm) { return false; }
#endif
/* cprm->dumpable is the snapshot of task dumpability at dump start. */
static inline bool coredump_force_suid_safe(const struct coredump_params *cprm)
{
/* Require nonrelative corefile path and be extra careful. */
return cprm->dumpable == TASK_DUMPABLE_ROOT;
}
static bool coredump_file(struct core_name *cn, struct coredump_params *cprm,
const struct linux_binfmt *binfmt)
{
struct mnt_idmap *idmap;
struct inode *inode;
struct file *file __free(fput) = NULL;
int open_flags = O_CREAT | O_WRONLY | O_NOFOLLOW | O_LARGEFILE | O_EXCL;
if (cprm->limit < binfmt->min_coredump)
return false;
if (coredump_force_suid_safe(cprm) && cn->corename[0] != '/') {
coredump_report_failure("this process can only dump core to a fully qualified path, skipping core dump");
return false;
}
/*
* Unlink the file if it exists unless this is a SUID
* binary - in that case, we're running around with root
* privs and don't want to unlink another user's coredump.
*/
if (!coredump_force_suid_safe(cprm)) {
CLASS(filename_kernel, name)(cn->corename);
/*
* If it doesn't exist, that's fine. If there's some
* other problem, we'll catch it at the filp_open().
*/
filename_unlinkat(AT_FDCWD, name);
}
/*
* There is a race between unlinking and creating the
* file, but if that causes an EEXIST here, that's
* fine - another process raced with us while creating
* the corefile, and the other process won. To userspace,
* what matters is that at least one of the two processes
* writes its coredump successfully, not which one.
*/
if (coredump_force_suid_safe(cprm)) {
/*
* Using user namespaces, normal user tasks can change
* their current->fs->root to point to arbitrary
* directories. Since the intention of the "only dump
* with a fully qualified path" rule is to control where
* coredumps may be placed using root privileges,
* current->fs->root must not be used. Instead, use the
* root directory of PID 1.
*/
scoped_with_init_fs()
file = filp_open(cn->corename, open_flags, 0600);
} else {
file = filp_open(cn->corename, open_flags, 0600);
}
if (IS_ERR(file))
return false;
inode = file_inode(file);
if (inode->i_nlink > 1)
return false;
if (d_unhashed(file->f_path.dentry))
return false;
/*
* AK: actually i see no reason to not allow this for named
* pipes etc, but keep the previous behaviour for now.
*/
if (!S_ISREG(inode->i_mode))
return false;
/*
* Don't dump core if the filesystem changed owner or mode
* of the file during file creation. This is an issue when
* a process dumps core while its cwd is e.g. on a vfat
* filesystem.
*/
idmap = file_mnt_idmap(file);
if (!vfsuid_eq_kuid(i_uid_into_vfsuid(idmap, inode), current_fsuid())) {
coredump_report_failure("Core dump to %s aborted: cannot preserve file owner", cn->corename);
return false;
}
if ((inode->i_mode & 0677) != 0600) {
coredump_report_failure("Core dump to %s aborted: cannot preserve file permissions", cn->corename);
return false;
}
if (!(file->f_mode & FMODE_CAN_WRITE))
return false;
if (do_truncate(idmap, file->f_path.dentry, 0, 0, file))
return false;
cprm->file = no_free_ptr(file);
return true;
}
static bool coredump_pipe(struct core_name *cn, struct coredump_params *cprm,
size_t *argv, int argc)
{
int argi;
char **helper_argv __free(kfree) = NULL;
struct subprocess_info *sub_info;
if (cprm->limit == 1) {
/* See umh_coredump_setup() which sets RLIMIT_CORE = 1.
*
* Normally core limits are irrelevant to pipes, since
* we're not writing to the file system, but we use
* cprm.limit of 1 here as a special value, this is a
* consistent way to catch recursive crashes.
* We can still crash if the core_pattern binary sets
* RLIM_CORE = !1, but it runs as root, and can do
* lots of stupid things.
*
* Note that we use task_tgid_vnr here to grab the pid
* of the process group leader. That way we get the
* right pid if a thread in a multi-threaded
* core_pattern process dies.
*/
coredump_report_failure("RLIMIT_CORE is set to 1, aborting core");
return false;
}
cprm->limit = RLIM_INFINITY;
cn->core_pipe_limit = atomic_inc_return(&core_pipe_count);
if (core_pipe_limit && (core_pipe_limit < cn->core_pipe_limit)) {
coredump_report_failure("over core_pipe_limit, skipping core dump");
return false;
}
helper_argv = kmalloc_array(argc + 1, sizeof(*helper_argv), GFP_KERNEL);
if (!helper_argv) {
coredump_report_failure("%s failed to allocate memory", __func__);
return false;
}
for (argi = 0; argi < argc; argi++)
helper_argv[argi] = cn->corename + argv[argi];
helper_argv[argi] = NULL;
sub_info = call_usermodehelper_setup(helper_argv[0], helper_argv, NULL,
GFP_KERNEL, umh_coredump_setup,
NULL, cprm);
if (!sub_info)
return false;
if (call_usermodehelper_exec(sub_info, UMH_WAIT_EXEC)) {
coredump_report_failure("|%s pipe failed", cn->corename);
return false;
}
/*
* umh disabled with CONFIG_STATIC_USERMODEHELPER_PATH="" would
* have this set to NULL.
*/
if (!cprm->file) {
coredump_report_failure("Core dump to |%s disabled", cn->corename);
return false;
}
return true;
}
static bool coredump_write(struct core_name *cn,
struct coredump_params *cprm,
const struct linux_binfmt *binfmt)
{
if (dump_interrupted())
return true;
if (!dump_vma_snapshot(cprm))
return false;
file_start_write(cprm->file);
cn->core_dumped = binfmt->core_dump(cprm);
/*
* Ensures that file size is big enough to contain the current
* file postion. This prevents gdb from complaining about
* a truncated file if the last "write" to the file was
* dump_skip.
*/
if (cprm->to_skip) {
cprm->to_skip--;
dump_emit(cprm, "", 1);
}
file_end_write(cprm->file);
free_vma_snapshot(cprm);
return true;
}
static void coredump_cleanup(struct core_name *cn, struct coredump_params *cprm)
{
if (cprm->file)
filp_close(cprm->file, NULL);
if (cn->core_pipe_limit) {
VFS_WARN_ON_ONCE(cn->core_type != COREDUMP_PIPE);
atomic_dec(&core_pipe_count);
}
kfree(cn->corename);
coredump_finish(cn->core_dumped);
}
static inline bool coredump_skip(const struct coredump_params *cprm,
const struct linux_binfmt *binfmt)
{
if (!binfmt)
return true;
if (!binfmt->core_dump)
return true;
if (cprm->dumpable == TASK_DUMPABLE_OFF)
return true;
return false;
}
static void do_coredump(struct core_name *cn, struct coredump_params *cprm,
size_t **argv, int *argc, const struct linux_binfmt *binfmt)
{
trace_coredump(cprm->siginfo->si_signo);
if (!coredump_parse(cn, cprm, argv, argc)) {
coredump_report_failure("format_corename failed, aborting core");
return;
}
switch (cn->core_type) {
case COREDUMP_FILE:
if (!coredump_file(cn, cprm, binfmt))
return;
break;
case COREDUMP_PIPE:
if (!coredump_pipe(cn, cprm, *argv, *argc))
return;
break;
case COREDUMP_SOCK_REQ:
fallthrough;
case COREDUMP_SOCK:
if (!coredump_socket(cn, cprm))
return;
break;
default:
WARN_ON_ONCE(true);
return;
}
/* Don't even generate the coredump. */
if (cn->mask & COREDUMP_REJECT)
return;
/* get us an unshared descriptor table; almost always a no-op */
/* The cell spufs coredump code reads the file descriptor tables */
if (unshare_files())
return;
if ((cn->mask & COREDUMP_KERNEL) && !coredump_write(cn, cprm, binfmt))
return;
coredump_sock_shutdown(cprm->file);
/* Let the parent know that a coredump was generated. */
if (cn->mask & COREDUMP_USERSPACE)
cn->core_dumped = true;
/*
* When core_pipe_limit is set we wait for the coredump server
* or usermodehelper to finish before exiting so it can e.g.,
* inspect /proc/<pid>.
*/
if (cn->mask & COREDUMP_WAIT) {
switch (cn->core_type) {
case COREDUMP_PIPE:
wait_for_dump_helpers(cprm->file);
break;
case COREDUMP_SOCK_REQ:
fallthrough;
case COREDUMP_SOCK:
coredump_sock_wait(cprm->file);
break;
default:
break;
}
}
}
void vfs_coredump(const kernel_siginfo_t *siginfo)
{
size_t *argv __free(kfree) = NULL;
struct core_state core_state;
struct core_name cn;
const struct mm_struct *mm = current->mm;
const struct linux_binfmt *binfmt = mm->binfmt;
int argc = 0;
struct coredump_params cprm = {
.siginfo = siginfo,
.limit = rlimit(RLIMIT_CORE),
/* Snapshot MMF_DUMP_FILTER_* (unlocked) and dumpable for the dump. */
.mm_flags = __mm_flags_get_word(mm),
.dumpable = task_exec_state_get_dumpable(current),
.vma_meta = NULL,
.cpu = raw_smp_processor_id(),
};
audit_core_dumps(siginfo->si_signo);
if (coredump_skip(&cprm, binfmt))
return;
CLASS(prepare_creds, cred)();
if (!cred)
return;
/*
* We cannot trust fsuid as being the "true" uid of the process
* nor do we know its entire history. We only know it was tainted
* so we dump it as root in mode 2, and only into a controlled
* environment (pipe handler or fully qualified path).
*/
if (coredump_force_suid_safe(&cprm))
cred->fsuid = GLOBAL_ROOT_UID;
if (coredump_wait(siginfo->si_signo, &core_state) < 0)
return;
scoped_with_creds(cred)
do_coredump(&cn, &cprm, &argv, &argc, binfmt);
coredump_cleanup(&cn, &cprm);
return;
}
/*
* Core dumping helper functions. These are the only things you should
* do on a core-file: use only these functions to write out all the
* necessary info.
*/
static int __dump_emit(struct coredump_params *cprm, const void *addr, int nr)
{
struct file *file = cprm->file;
loff_t pos = file->f_pos;
ssize_t n;
if (cprm->written + nr > cprm->limit)
return 0;
if (dump_interrupted())
return 0;
n = __kernel_write(file, addr, nr, &pos);
if (n != nr)
return 0;
file->f_pos = pos;
cprm->written += n;
cprm->pos += n;
return 1;
}
static int __dump_skip(struct coredump_params *cprm, size_t nr)
{
static char zeroes[PAGE_SIZE];
struct file *file = cprm->file;
if (file->f_mode & FMODE_LSEEK) {
if (dump_interrupted() || vfs_llseek(file, nr, SEEK_CUR) < 0)
return 0;
cprm->pos += nr;
return 1;
}
while (nr > PAGE_SIZE) {
if (!__dump_emit(cprm, zeroes, PAGE_SIZE))
return 0;
nr -= PAGE_SIZE;
}
return __dump_emit(cprm, zeroes, nr);
}
int dump_emit(struct coredump_params *cprm, const void *addr, int nr)
{
if (cprm->to_skip) {
if (!__dump_skip(cprm, cprm->to_skip))
return 0;
cprm->to_skip = 0;
}
return __dump_emit(cprm, addr, nr);
}
EXPORT_SYMBOL(dump_emit);
void dump_skip_to(struct coredump_params *cprm, unsigned long pos)
{
cprm->to_skip = pos - cprm->pos;
}
EXPORT_SYMBOL(dump_skip_to);
void dump_skip(struct coredump_params *cprm, size_t nr)
{
cprm->to_skip += nr;
}
EXPORT_SYMBOL(dump_skip);
#ifdef CONFIG_ELF_CORE
static int dump_emit_page(struct coredump_params *cprm, struct page *page)
{
struct bio_vec bvec;
struct iov_iter iter;
struct file *file = cprm->file;
loff_t pos;
ssize_t n;
if (!page)
return 0;
if (cprm->to_skip) {
if (!__dump_skip(cprm, cprm->to_skip))
return 0;
cprm->to_skip = 0;
}
if (cprm->written + PAGE_SIZE > cprm->limit)
return 0;
if (dump_interrupted())
return 0;
pos = file->f_pos;
bvec_set_page(&bvec, page, PAGE_SIZE, 0);
iov_iter_bvec(&iter, ITER_SOURCE, &bvec, 1, PAGE_SIZE);
n = __kernel_write_iter(cprm->file, &iter, &pos);
if (n != PAGE_SIZE)
return 0;
file->f_pos = pos;
cprm->written += PAGE_SIZE;
cprm->pos += PAGE_SIZE;
return 1;
}
/*
* If we might get machine checks from kernel accesses during the
* core dump, let's get those errors early rather than during the
* IO. This is not performance-critical enough to warrant having
* all the machine check logic in the iovec paths.
*/
#ifdef copy_mc_to_kernel
#define dump_page_alloc() alloc_page(GFP_KERNEL)
#define dump_page_free(x) __free_page(x)
static struct page *dump_page_copy(struct page *src, struct page *dst)
{
void *buf = kmap_local_page(src);
size_t left = copy_mc_to_kernel(page_address(dst), buf, PAGE_SIZE);
kunmap_local(buf);
return left ? NULL : dst;
}
#else
/* We just want to return non-NULL; it's never used. */
#define dump_page_alloc() ERR_PTR(-EINVAL)
#define dump_page_free(x) ((void)(x))
static inline struct page *dump_page_copy(struct page *src, struct page *dst)
{
return src;
}
#endif
int dump_user_range(struct coredump_params *cprm, unsigned long start,
unsigned long len)
{
unsigned long addr;
struct page *dump_page;
int locked, ret;
dump_page = dump_page_alloc();
if (!dump_page)
return 0;
ret = 0;
locked = 0;
for (addr = start; addr < start + len; addr += PAGE_SIZE) {
struct page *page;
if (!locked) {
if (mmap_read_lock_killable(current->mm))
goto out;
locked = 1;
}
/*
* To avoid having to allocate page tables for virtual address
* ranges that have never been used yet, and also to make it
* easy to generate sparse core files, use a helper that returns
* NULL when encountering an empty page table entry that would
* otherwise have been filled with the zero page.
*/
page = get_dump_page(addr, &locked);
if (page) {
if (locked) {
mmap_read_unlock(current->mm);
locked = 0;
}
int stop = !dump_emit_page(cprm, dump_page_copy(page, dump_page));
put_page(page);
if (stop)
goto out;
} else {
dump_skip(cprm, PAGE_SIZE);
}
if (dump_interrupted())
goto out;
if (!need_resched())
continue;
if (locked) {
mmap_read_unlock(current->mm);
locked = 0;
}
cond_resched();
}
ret = 1;
out:
if (locked)
mmap_read_unlock(current->mm);
dump_page_free(dump_page);
return ret;
}
#endif
int dump_align(struct coredump_params *cprm, int align)
{
unsigned mod = (cprm->pos + cprm->to_skip) & (align - 1);
if (align & (align - 1))
return 0;
if (mod)
cprm->to_skip += align - mod;
return 1;
}
EXPORT_SYMBOL(dump_align);
#ifdef CONFIG_SYSCTL
void validate_coredump_safety(void)
{
if (suid_dumpable == TASK_DUMPABLE_ROOT &&
core_pattern[0] != '/' && core_pattern[0] != '|' && core_pattern[0] != '@') {
coredump_report_failure("Unsafe core_pattern used with fs.suid_dumpable=2: "
"pipe handler or fully qualified core dump path required. "
"Set kernel.core_pattern before fs.suid_dumpable.");
}
}
static inline bool check_coredump_socket(void)
{
const char *p;
if (core_pattern[0] != '@')
return true;
/*
* Coredump socket must be located in the initial mount
* namespace. Don't give the impression that anything else is
* supported right now.
*/
if (current->nsproxy->mnt_ns != init_task.nsproxy->mnt_ns)
return false;
/* Must be an absolute path... */
if (core_pattern[1] != '/') {
/* ... or the socket request protocol... */
if (core_pattern[1] != '@')
return false;
/* ... and if so must be an absolute path. */
if (core_pattern[2] != '/')
return false;
p = &core_pattern[2];
} else {
p = &core_pattern[1];
}
/* The path obviously cannot exceed UNIX_PATH_MAX. */
if (strlen(p) >= UNIX_PATH_MAX)
return false;
/* Must not contain ".." in the path. */
if (name_contains_dotdot(core_pattern))
return false;
return true;
}
static int proc_dostring_coredump(const struct ctl_table *table, int write,
void *buffer, size_t *lenp, loff_t *ppos)
{
int error;
ssize_t retval;
char old_core_pattern[CORENAME_MAX_SIZE];
if (!write)
return proc_dostring(table, write, buffer, lenp, ppos);
retval = strscpy(old_core_pattern, core_pattern, CORENAME_MAX_SIZE);
error = proc_dostring(table, write, buffer, lenp, ppos);
if (error)
return error;
if (!check_coredump_socket()) {
strscpy(core_pattern, old_core_pattern, retval + 1);
return -EINVAL;
}
if (strncmp(old_core_pattern, core_pattern, CORENAME_MAX_SIZE))
validate_coredump_safety();
return error;
}
static const unsigned int core_file_note_size_min = CORE_FILE_NOTE_SIZE_DEFAULT;
static const unsigned int core_file_note_size_max = CORE_FILE_NOTE_SIZE_MAX;
static char core_modes[] = {
"file\npipe"
#ifdef CONFIG_UNIX
"\nsocket"
#endif
};
static const struct ctl_table coredump_sysctls[] = {
{
.procname = "core_uses_pid",
.data = &core_uses_pid,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
.procname = "core_pattern",
.data = core_pattern,
.maxlen = CORENAME_MAX_SIZE,
.mode = 0644,
.proc_handler = proc_dostring_coredump,
},
{
.procname = "core_pipe_limit",
.data = &core_pipe_limit,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_INT_MAX,
},
{
.procname = "core_file_note_size_limit",
.data = &core_file_note_size_limit,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_douintvec_minmax,
.extra1 = (unsigned int *)&core_file_note_size_min,
.extra2 = (unsigned int *)&core_file_note_size_max,
},
{
.procname = "core_sort_vma",
.data = &core_sort_vma,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_douintvec_minmax,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_ONE,
},
{
.procname = "core_modes",
.data = core_modes,
.maxlen = sizeof(core_modes) - 1,
.mode = 0444,
.proc_handler = proc_dostring,
},
};
static int __init init_fs_coredump_sysctls(void)
{
register_sysctl_init("kernel", coredump_sysctls);
return 0;
}
fs_initcall(init_fs_coredump_sysctls);
#endif /* CONFIG_SYSCTL */
/*
* The purpose of always_dump_vma() is to make sure that special kernel mappings
* that are useful for post-mortem analysis are included in every core dump.
* In that way we ensure that the core dump is fully interpretable later
* without matching up the same kernel and hardware config to see what PC values
* meant. These special mappings include - vDSO, vsyscall, and other
* architecture specific mappings
*/
static bool always_dump_vma(struct vm_area_struct *vma)
{
/* Any vsyscall mappings? */
if (vma == get_gate_vma(vma->vm_mm))
return true;
/*
* Assume that all vmas with a .name op should always be dumped.
* If this changes, a new vm_ops field can easily be added.
*/
if (vma->vm_ops && vma->vm_ops->name && vma->vm_ops->name(vma))
return true;
/*
* arch_vma_name() returns non-NULL for special architecture mappings,
* such as vDSO sections.
*/
if (arch_vma_name(vma))
return true;
return false;
}
#define DUMP_SIZE_MAYBE_ELFHDR_PLACEHOLDER 1
/*
* Decide how much of @vma's contents should be included in a core dump.
*/
static unsigned long vma_dump_size(struct vm_area_struct *vma,
unsigned long mm_flags)
{
#define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type))
/* always dump the vdso and vsyscall sections */
if (always_dump_vma(vma))
goto whole;
if (vma->vm_flags & VM_DONTDUMP)
return 0;
/* support for DAX */
if (vma_is_dax(vma)) {
if ((vma->vm_flags & VM_SHARED) && FILTER(DAX_SHARED))
goto whole;
if (!(vma->vm_flags & VM_SHARED) && FILTER(DAX_PRIVATE))
goto whole;
return 0;
}
/* Hugetlb memory check */
if (is_vm_hugetlb_page(vma)) {
if ((vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_SHARED))
goto whole;
if (!(vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_PRIVATE))
goto whole;
return 0;
}
/* Do not dump I/O mapped devices or special mappings */
if (vma->vm_flags & VM_IO)
return 0;
/* By default, dump shared memory if mapped from an anonymous file. */
if (vma->vm_flags & VM_SHARED) {
if (file_inode(vma->vm_file)->i_nlink == 0 ?
FILTER(ANON_SHARED) : FILTER(MAPPED_SHARED))
goto whole;
return 0;
}
/* Dump segments that have been written to. */
if ((!IS_ENABLED(CONFIG_MMU) || vma->anon_vma) && FILTER(ANON_PRIVATE))
goto whole;
if (vma->vm_file == NULL)
return 0;
if (FILTER(MAPPED_PRIVATE))
goto whole;
/*
* If this is the beginning of an executable file mapping,
* dump the first page to aid in determining what was mapped here.
*/
if (FILTER(ELF_HEADERS) &&
vma->vm_pgoff == 0 && (vma->vm_flags & VM_READ)) {
if ((READ_ONCE(file_inode(vma->vm_file)->i_mode) & 0111) != 0)
return PAGE_SIZE;
/*
* ELF libraries aren't always executable.
* We'll want to check whether the mapping starts with the ELF
* magic, but not now - we're holding the mmap lock,
* so copy_from_user() doesn't work here.
* Use a placeholder instead, and fix it up later in
* dump_vma_snapshot().
*/
return DUMP_SIZE_MAYBE_ELFHDR_PLACEHOLDER;
}
#undef FILTER
return 0;
whole:
return vma->vm_end - vma->vm_start;
}
/*
* Helper function for iterating across a vma list. It ensures that the caller
* will visit `gate_vma' prior to terminating the search.
*/
static struct vm_area_struct *coredump_next_vma(struct vma_iterator *vmi,
struct vm_area_struct *vma,
struct vm_area_struct *gate_vma)
{
if (gate_vma && (vma == gate_vma))
return NULL;
vma = vma_next(vmi);
if (vma)
return vma;
return gate_vma;
}
static void free_vma_snapshot(struct coredump_params *cprm)
{
if (cprm->vma_meta) {
int i;
for (i = 0; i < cprm->vma_count; i++) {
struct file *file = cprm->vma_meta[i].file;
if (file)
fput(file);
}
kvfree(cprm->vma_meta);
cprm->vma_meta = NULL;
}
}
static int cmp_vma_size(const void *vma_meta_lhs_ptr, const void *vma_meta_rhs_ptr)
{
const struct core_vma_metadata *vma_meta_lhs = vma_meta_lhs_ptr;
const struct core_vma_metadata *vma_meta_rhs = vma_meta_rhs_ptr;
if (vma_meta_lhs->dump_size < vma_meta_rhs->dump_size)
return -1;
if (vma_meta_lhs->dump_size > vma_meta_rhs->dump_size)
return 1;
return 0;
}
/*
* Under the mmap_lock, take a snapshot of relevant information about the task's
* VMAs.
*/
static bool dump_vma_snapshot(struct coredump_params *cprm)
{
struct vm_area_struct *gate_vma, *vma = NULL;
struct mm_struct *mm = current->mm;
VMA_ITERATOR(vmi, mm, 0);
int i = 0;
/*
* Once the stack expansion code is fixed to not change VMA bounds
* under mmap_lock in read mode, this can be changed to take the
* mmap_lock in read mode.
*/
if (mmap_write_lock_killable(mm))
return false;
cprm->vma_data_size = 0;
gate_vma = get_gate_vma(mm);
cprm->vma_count = mm->map_count + (gate_vma ? 1 : 0);
cprm->vma_meta = kvmalloc_objs(*cprm->vma_meta, cprm->vma_count);
if (!cprm->vma_meta) {
mmap_write_unlock(mm);
return false;
}
while ((vma = coredump_next_vma(&vmi, vma, gate_vma)) != NULL) {
struct core_vma_metadata *m = cprm->vma_meta + i;
m->start = vma->vm_start;
m->end = vma->vm_end;
m->flags = vma->vm_flags;
m->dump_size = vma_dump_size(vma, cprm->mm_flags);
m->pgoff = vma->vm_pgoff;
m->file = vma->vm_file;
if (m->file)
get_file(m->file);
i++;
}
mmap_write_unlock(mm);
for (i = 0; i < cprm->vma_count; i++) {
struct core_vma_metadata *m = cprm->vma_meta + i;
if (m->dump_size == DUMP_SIZE_MAYBE_ELFHDR_PLACEHOLDER) {
char elfmag[SELFMAG];
if (copy_from_user(elfmag, (void __user *)m->start, SELFMAG) ||
memcmp(elfmag, ELFMAG, SELFMAG) != 0) {
m->dump_size = 0;
} else {
m->dump_size = PAGE_SIZE;
}
}
cprm->vma_data_size += m->dump_size;
}
if (core_sort_vma)
sort(cprm->vma_meta, cprm->vma_count, sizeof(*cprm->vma_meta),
cmp_vma_size, NULL);
return true;
}
