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[46.135.14.82]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-477625c2f90sm8914505e9.12.2025.11.05.13.20.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 05 Nov 2025 13:20:34 -0800 (PST) From: Mateusz Guzik To: mic@digikod.net, brauner@kernel.org Cc: linux-security-module@vger.kernel.org, linux-fsdevel@vger.kernel.org, viro@zeniv.linux.org.uk, eadavis@qq.com, gnoack@google.com, jack@suse.cz, jannh@google.com, max.kellermann@ionos.com, m@maowtm.org, syzbot+12479ae15958fc3f54ec@syzkaller.appspotmail.com, Mateusz Guzik Subject: [PATCH 1/2] fs: add iput_not_last() Date: Wed, 5 Nov 2025 22:20:24 +0100 Message-ID: <20251105212025.807549-1-mjguzik@gmail.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Signed-off-by: Mateusz Guzik --- fs/inode.c | 12 ++++++++++++ include/linux/fs.h | 1 + 2 files changed, 13 insertions(+) diff --git a/fs/inode.c b/fs/inode.c index ec9339024ac3..cff1d3af0d57 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -1967,6 +1967,18 @@ void iput(struct inode *inode) } EXPORT_SYMBOL(iput); +/** + * iput_not_last - put an inode assuming this is not the last reference + * @inode: inode to put + */ +void iput_not_last(struct inode *inode) +{ + VFS_BUG_ON_INODE(atomic_read(&inode->i_count) < 2, inode); + + WARN_ON(atomic_sub_return(1, &inode->i_count) == 0); +} +EXPORT_SYMBOL(iput_not_last); + #ifdef CONFIG_BLOCK /** * bmap - find a block number in a file diff --git a/include/linux/fs.h b/include/linux/fs.h index c895146c1444..98fc088a461f 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2823,6 +2823,7 @@ extern int current_umask(void); extern void ihold(struct inode * inode); extern void iput(struct inode *); +void iput_not_last(struct inode *); int inode_update_timestamps(struct inode *inode, int flags); int generic_update_time(struct inode *, int); -- 2.48.1