| Message ID | 20220908145011.21212-1-mdoucha@suse.cz |
|---|---|
| State | Accepted |
| Headers | show |
| Series | inotify11: Fix race condition between fork() and inotify init | expand |
On Thu, Sep 8, 2022 at 5:50 PM Martin Doucha <mdoucha@suse.cz> wrote: > > When the child process runs a few churn cycles before the parent completes > inotify initialization, the parent will get stuck reading the inotify > file descriptor until it eventually times out. Create inotify watch > befory fork()ing to prevent this race condition. > > Signed-off-by: Martin Doucha <mdoucha@suse.cz> LGTM Reviewed-by: Amir Goldstein <amir73il@gmail.com> > --- > testcases/kernel/syscalls/inotify/inotify11.c | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) > > diff --git a/testcases/kernel/syscalls/inotify/inotify11.c b/testcases/kernel/syscalls/inotify/inotify11.c > index e426f9e1c..dd32ea7fd 100644 > --- a/testcases/kernel/syscalls/inotify/inotify11.c > +++ b/testcases/kernel/syscalls/inotify/inotify11.c > @@ -61,15 +61,16 @@ static void verify_inotify(void) > struct inotify_event *event; > int inotify_fd; > > + inotify_fd = SAFE_MYINOTIFY_INIT(); > + SAFE_MYINOTIFY_ADD_WATCH(inotify_fd, ".", IN_DELETE); > + > pid = SAFE_FORK(); > if (pid == 0) { > + SAFE_CLOSE(inotify_fd); > churn(); > return; > } > > - inotify_fd = SAFE_MYINOTIFY_INIT(); > - SAFE_MYINOTIFY_ADD_WATCH(inotify_fd, ".", IN_DELETE); > - > while (!opened && nevents < CHURN_FILES) { > int i, fd, len; > > -- > 2.37.2 > > > -- > Mailing list info: https://lists.linux.it/listinfo/ltp
Hi all, thanks, merged! Kind regards, Petr
diff --git a/testcases/kernel/syscalls/inotify/inotify11.c b/testcases/kernel/syscalls/inotify/inotify11.c index e426f9e1c..dd32ea7fd 100644 --- a/testcases/kernel/syscalls/inotify/inotify11.c +++ b/testcases/kernel/syscalls/inotify/inotify11.c @@ -61,15 +61,16 @@ static void verify_inotify(void) struct inotify_event *event; int inotify_fd; + inotify_fd = SAFE_MYINOTIFY_INIT(); + SAFE_MYINOTIFY_ADD_WATCH(inotify_fd, ".", IN_DELETE); + pid = SAFE_FORK(); if (pid == 0) { + SAFE_CLOSE(inotify_fd); churn(); return; } - inotify_fd = SAFE_MYINOTIFY_INIT(); - SAFE_MYINOTIFY_ADD_WATCH(inotify_fd, ".", IN_DELETE); - while (!opened && nevents < CHURN_FILES) { int i, fd, len;
When the child process runs a few churn cycles before the parent completes inotify initialization, the parent will get stuck reading the inotify file descriptor until it eventually times out. Create inotify watch befory fork()ing to prevent this race condition. Signed-off-by: Martin Doucha <mdoucha@suse.cz> --- testcases/kernel/syscalls/inotify/inotify11.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)