| Message ID | 20241129185642.6483-1-leocstone@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [f2fs-dev,v2] f2fs: Add check for deleted inode | expand |
On 2024/11/30 2:56, Leo Stone wrote: > The syzbot reproducer mounts a f2fs image, then tries to unlink an > existing file. However, the unlinked file already has a link count of 0 > when it is read for the first time in do_read_inode(). > > Add a check to sanity_check_inode() for i_nlink == 0. > > Reported-by: syzbot+b01a36acd7007e273a83@syzkaller.appspotmail.com > Closes: https://syzkaller.appspot.com/bug?extid=b01a36acd7007e273a83 > Fixes: 5d64600d4f33 ("f2fs: avoid bug_on on corrupted inode") 39a53e0ce0df ("f2fs: add superblock and major in-memory structure")? Due to it missed to do sanity check on i_nlink in initialization version of f2fs. Thanks, Thanks, > Signed-off-by: Leo Stone <leocstone@gmail.com> > --- > v2: Correct "Fixes" line > v1: https://lore.kernel.org/all/20241124010459.23283-1-leocstone@gmail.com/T/ > --- > fs/f2fs/inode.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c > index 1ed86df343a5..65f1dc32f173 100644 > --- a/fs/f2fs/inode.c > +++ b/fs/f2fs/inode.c > @@ -372,6 +372,12 @@ static bool sanity_check_inode(struct inode *inode, struct page *node_page) > return false; > } > > + if (inode->i_nlink == 0) { > + f2fs_warn(sbi, "%s: inode (ino=%lx) has a link count of 0", > + __func__, inode->i_ino); > + return false; > + } > + > return true; > } >
diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c index 1ed86df343a5..65f1dc32f173 100644 --- a/fs/f2fs/inode.c +++ b/fs/f2fs/inode.c @@ -372,6 +372,12 @@ static bool sanity_check_inode(struct inode *inode, struct page *node_page) return false; } + if (inode->i_nlink == 0) { + f2fs_warn(sbi, "%s: inode (ino=%lx) has a link count of 0", + __func__, inode->i_ino); + return false; + } + return true; }
The syzbot reproducer mounts a f2fs image, then tries to unlink an existing file. However, the unlinked file already has a link count of 0 when it is read for the first time in do_read_inode(). Add a check to sanity_check_inode() for i_nlink == 0. Reported-by: syzbot+b01a36acd7007e273a83@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=b01a36acd7007e273a83 Fixes: 5d64600d4f33 ("f2fs: avoid bug_on on corrupted inode") Signed-off-by: Leo Stone <leocstone@gmail.com> --- v2: Correct "Fixes" line v1: https://lore.kernel.org/all/20241124010459.23283-1-leocstone@gmail.com/T/ --- fs/f2fs/inode.c | 6 ++++++ 1 file changed, 6 insertions(+)