SymbX/systemd
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

process-util: introduce FORK_NEW_NETNS for safe_fork()

Browse Source 
Similar to FORK_NEW_MOUNTNS or FORK_NEW_USERNS.
This commit is contained in:
Yu Watanabe
2024-01-19 15:06:08 +09:00
parent cb566b5d13
commit 387f39ea30
2 changed files with 9 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/basic/process-util.c
+3 -2
View File
@@ -1541,10 +1541,11 @@ int safe_fork_full(
}
}
if ((flags & (FORK_NEW_MOUNTNS|FORK_NEW_USERNS)) != 0)
if ((flags & (FORK_NEW_MOUNTNS|FORK_NEW_USERNS|FORK_NEW_NETNS)) != 0)
pid = raw_clone(SIGCHLD|
(FLAGS_SET(flags, FORK_NEW_MOUNTNS) ? CLONE_NEWNS : 0) |
(FLAGS_SET(flags, FORK_NEW_USERNS) ? CLONE_NEWUSER : 0));
(FLAGS_SET(flags, FORK_NEW_USERNS) ? CLONE_NEWUSER : 0) |
(FLAGS_SET(flags, FORK_NEW_NETNS) ? CLONE_NEWNET : 0));
else
pid = fork();
if (pid < 0)
src/basic/process-util.h
+6 -5
View File
@@ -154,11 +154,11 @@ int must_be_root(void);
pid_t clone_with_nested_stack(int (*fn)(void *), int flags, void *userdata);
/* 💣 Note that FORK_NEW_USERNS + FORK_NEW_MOUNTNS should not be called in threaded programs, because they
* cause us to use raw_clone() which does not synchronize the glibc malloc() locks, and thus will cause
* deadlocks if the parent uses threads and the child does memory allocations. Hence: if the parent is
* threaded these flags may not be used. These flags cannot be used if the parent uses threads or the child
* uses malloc(). 💣 */
/* 💣 Note that FORK_NEW_USERNS, FORK_NEW_MOUNTNS, or FORK_NEW_NETNS should not be called in threaded
* programs, because they cause us to use raw_clone() which does not synchronize the glibc malloc() locks,
* and thus will cause deadlocks if the parent uses threads and the child does memory allocations. Hence: if
* the parent is threaded these flags may not be used. These flags cannot be used if the parent uses threads
* or the child uses malloc(). 💣 */
typedef enum ForkFlags {
FORK_RESET_SIGNALS = 1 << 0, /* Reset all signal handlers and signal mask */
FORK_CLOSE_ALL_FDS = 1 << 1, /* Close all open file descriptors in the child, except for 0,1,2 */
@@ -179,6 +179,7 @@ typedef enum ForkFlags {
FORK_CLOEXEC_OFF = 1 << 16, /* In the child: turn off O_CLOEXEC on all fds in except_fds[] */
FORK_KEEP_NOTIFY_SOCKET = 1 << 17, /* Unless this specified, $NOTIFY_SOCKET will be unset. */
FORK_DETACH = 1 << 18, /* Double fork if needed to ensure PID1/subreaper is parent */
FORK_NEW_NETNS = 1 << 19, /* Run child in its own network namespace 💣 DO NOT USE IN THREADED PROGRAMS! 💣 */
} ForkFlags;
int safe_fork_full(