diff options
| author | Richard Weinberger <richard@nod.at> | 2015-08-09 22:49:07 +0300 |
|---|---|---|
| committer | Richard Weinberger <richard@nod.at> | 2015-10-19 23:53:37 +0300 |
| commit | 6b1873371cea13036171d03a7c1e3e59158b4505 (patch) | |
| tree | 01d0d2b9d72eea0300a081531ab6b9f302afe670 /arch/um/os-Linux | |
| parent | 37e81a016cc847c03ea71570fea29f12ca390bee (diff) | |
| download | linux-6b1873371cea13036171d03a7c1e3e59158b4505.tar.xz | |
um: Fix waitpid() usage in helper code
If UML is executing a helper program it is using
waitpid() with the __WCLONE flag to wait for the program
as the helper is executed from a clone()'ed thread.
While using __WCLONE is perfectly fine for clone()'ed
childs it won't detect terminated childs if the helper
has issued an execve().
We have to use __WALL to wait for both clone()'ed and
regular childs to detect the termination before and
after an execve().
Reported-and-tested-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
Diffstat (limited to 'arch/um/os-Linux')
| -rw-r--r-- | arch/um/os-Linux/helper.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/um/os-Linux/helper.c b/arch/um/os-Linux/helper.c index e3ee4a51ef63..3f02d4232812 100644 --- a/arch/um/os-Linux/helper.c +++ b/arch/um/os-Linux/helper.c @@ -96,7 +96,7 @@ int run_helper(void (*pre_exec)(void *), void *pre_data, char **argv) "ret = %d\n", -n); ret = n; } - CATCH_EINTR(waitpid(pid, NULL, __WCLONE)); + CATCH_EINTR(waitpid(pid, NULL, __WALL)); } out_free2: @@ -129,7 +129,7 @@ int run_helper_thread(int (*proc)(void *), void *arg, unsigned int flags, return err; } if (stack_out == NULL) { - CATCH_EINTR(pid = waitpid(pid, &status, __WCLONE)); + CATCH_EINTR(pid = waitpid(pid, &status, __WALL)); if (pid < 0) { err = -errno; printk(UM_KERN_ERR "run_helper_thread - wait failed, " @@ -148,7 +148,7 @@ int run_helper_thread(int (*proc)(void *), void *arg, unsigned int flags, int helper_wait(int pid) { int ret, status; - int wflags = __WCLONE; + int wflags = __WALL; CATCH_EINTR(ret = waitpid(pid, &status, wflags)); if (ret < 0) { |