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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-23 03:11:38 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-23 03:11:38 +0300 |
| commit | f320ac6e131669345c7f4abefbb228b570eb9199 (patch) | |
| tree | ec1e3f0d43b3ebfdcacfd8f47a649ce36f9dba6a | |
| parent | c3d8f220d01220a5b253e422be407d068dc65511 (diff) | |
| parent | 52c479697c9b73f628140dcdfcd39ea302d05482 (diff) | |
| download | linux-f320ac6e131669345c7f4abefbb228b570eb9199.tar.xz | |
Merge branch 'work.epoll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull epoll fixes from Al Viro:
"Fix reference counting and clean up exit paths"
* 'work.epoll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
do_epoll_ctl(): clean the failure exits up a bit
epoll: Keep a reference on files added to the check list
| -rw-r--r-- | fs/eventpoll.c | 26 |
1 files changed, 13 insertions, 13 deletions
diff --git a/fs/eventpoll.c b/fs/eventpoll.c index 12eebcdea9c8..e0decff22ae2 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -1994,9 +1994,11 @@ static int ep_loop_check_proc(void *priv, void *cookie, int call_nests) * not already there, and calling reverse_path_check() * during ep_insert(). */ - if (list_empty(&epi->ffd.file->f_tfile_llink)) + if (list_empty(&epi->ffd.file->f_tfile_llink)) { + get_file(epi->ffd.file); list_add(&epi->ffd.file->f_tfile_llink, &tfile_check_list); + } } } mutex_unlock(&ep->mtx); @@ -2040,6 +2042,7 @@ static void clear_tfile_check_list(void) file = list_first_entry(&tfile_check_list, struct file, f_tfile_llink); list_del_init(&file->f_tfile_llink); + fput(file); } INIT_LIST_HEAD(&tfile_check_list); } @@ -2200,25 +2203,22 @@ int do_epoll_ctl(int epfd, int op, int fd, struct epoll_event *epds, full_check = 1; if (is_file_epoll(tf.file)) { error = -ELOOP; - if (ep_loop_check(ep, tf.file) != 0) { - clear_tfile_check_list(); + if (ep_loop_check(ep, tf.file) != 0) goto error_tgt_fput; - } - } else + } else { + get_file(tf.file); list_add(&tf.file->f_tfile_llink, &tfile_check_list); + } error = epoll_mutex_lock(&ep->mtx, 0, nonblock); - if (error) { -out_del: - list_del(&tf.file->f_tfile_llink); + if (error) goto error_tgt_fput; - } if (is_file_epoll(tf.file)) { tep = tf.file->private_data; error = epoll_mutex_lock(&tep->mtx, 1, nonblock); if (error) { mutex_unlock(&ep->mtx); - goto out_del; + goto error_tgt_fput; } } } @@ -2239,8 +2239,6 @@ out_del: error = ep_insert(ep, epds, tf.file, fd, full_check); } else error = -EEXIST; - if (full_check) - clear_tfile_check_list(); break; case EPOLL_CTL_DEL: if (epi) @@ -2263,8 +2261,10 @@ out_del: mutex_unlock(&ep->mtx); error_tgt_fput: - if (full_check) + if (full_check) { + clear_tfile_check_list(); mutex_unlock(&epmutex); + } fdput(tf); error_fput: |