lkml.org 
[lkml]   [2020]   [Oct]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 4.14 29/70] ep_create_wakeup_source(): dentry name can change under you...
    Date
    From: Al Viro <viro@zeniv.linux.org.uk>

    commit 3701cb59d892b88d569427586f01491552f377b1 upstream.

    or get freed, for that matter, if it's a long (separately stored)
    name.

    Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    ---
    fs/eventpoll.c | 7 ++++---
    1 file changed, 4 insertions(+), 3 deletions(-)

    --- a/fs/eventpoll.c
    +++ b/fs/eventpoll.c
    @@ -1389,7 +1389,7 @@ static int reverse_path_check(void)

    static int ep_create_wakeup_source(struct epitem *epi)
    {
    - const char *name;
    + struct name_snapshot n;
    struct wakeup_source *ws;

    if (!epi->ep->ws) {
    @@ -1398,8 +1398,9 @@ static int ep_create_wakeup_source(struc
    return -ENOMEM;
    }

    - name = epi->ffd.file->f_path.dentry->d_name.name;
    - ws = wakeup_source_register(name);
    + take_dentry_name_snapshot(&n, epi->ffd.file->f_path.dentry);
    + ws = wakeup_source_register(n.name);
    + release_dentry_name_snapshot(&n);

    if (!ws)
    return -ENOMEM;

    \
     
     \ /
      Last update: 2020-10-12 16:10    [W:4.116 / U:0.208 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site