From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 48C397C0A9; Mon, 8 Apr 2024 13:56:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712584600; cv=none; b=gsg/YEMp186sCpIea16WBPvsQP1B5Xvjo1PhqLXmrl65AKcvMzOqHSkIH3lHw7DbXzex4eovO7T6MH0PtyzX3EJ9mBa8c5D5Hl43uoVYhYDhX8F5L2gGw6AgWb+MW3tiTcWAAks0X5ys8frHqm9p1YDxLTmrlHZ61f+3bvoGF/w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712584600; c=relaxed/simple; bh=21WdDhVt549/+0Gy9+mDe3/UbBk4SSIlfJXRqrQuXLU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=AnfvObB/FUn4ALjzKJvAALbDvJCdoxffo8cqDsRdvJBWqL0m8NK95MwVwGKckBy/hDOB9Md1uhPuEgGI5g9jNJZmUF/8/F1YDJPhivkWcr3fVxA2mlyh2NY4+4G63HwxxtlJSvfI+E2Iygo39APv0CFe2Xila71h2GwC3xjIZ1s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=VT4DDOk1; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="VT4DDOk1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C2C71C43390; Mon, 8 Apr 2024 13:56:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1712584600; bh=21WdDhVt549/+0Gy9+mDe3/UbBk4SSIlfJXRqrQuXLU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VT4DDOk11wNWICMjYUNYuay+1euOHdysOqyyiI0akyHjabCJD7Sn5Y2l6Lfkmjprc T6vkVDLMZHfVCDauHyR5sXN69yFggsGzkdtMQLUuSdGgxFW1JSC5YPryNC0yy+1+kz csFB2uLuFO7ZXPY/o4N5KarwxktDLGobAfRWn2s4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Christoph Hellwig , Jeff Layton , Chuck Lever Subject: [PATCH 5.15 494/690] filelock: add a new locks_inode_context accessor function Date: Mon, 8 Apr 2024 14:56:00 +0200 Message-ID: <20240408125417.531362312@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240408125359.506372836@linuxfoundation.org> References: <20240408125359.506372836@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jeff Layton [ Upstream commit 401a8b8fd5acd51582b15238d72a8d0edd580e9f ] There are a number of places in the kernel that are accessing the inode->i_flctx field without smp_load_acquire. This is required to ensure that the caller doesn't see a partially-initialized structure. Add a new accessor function for it to make this clear and convert all of the relevant accesses in locks.c to use it. Also, convert locks_free_lock_context to use the helper as well instead of just doing a "bare" assignment. Reviewed-by: Christoph Hellwig Signed-off-by: Jeff Layton Stable-dep-of: 77c67530e1f9 ("nfsd: use locks_inode_context helper") Signed-off-by: Chuck Lever --- fs/locks.c | 24 ++++++++++++------------ include/linux/fs.h | 14 ++++++++++++++ 2 files changed, 26 insertions(+), 12 deletions(-) diff --git a/fs/locks.c b/fs/locks.c index 317c2ec17b943..77781b71bcaab 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -251,7 +251,7 @@ locks_get_lock_context(struct inode *inode, int type) struct file_lock_context *ctx; /* paired with cmpxchg() below */ - ctx = smp_load_acquire(&inode->i_flctx); + ctx = locks_inode_context(inode); if (likely(ctx) || type == F_UNLCK) goto out; @@ -270,7 +270,7 @@ locks_get_lock_context(struct inode *inode, int type) */ if (cmpxchg(&inode->i_flctx, NULL, ctx)) { kmem_cache_free(flctx_cache, ctx); - ctx = smp_load_acquire(&inode->i_flctx); + ctx = locks_inode_context(inode); } out: trace_locks_get_lock_context(inode, type, ctx); @@ -323,7 +323,7 @@ locks_check_ctx_file_list(struct file *filp, struct list_head *list, void locks_free_lock_context(struct inode *inode) { - struct file_lock_context *ctx = inode->i_flctx; + struct file_lock_context *ctx = locks_inode_context(inode); if (unlikely(ctx)) { locks_check_ctx_lists(inode); @@ -985,7 +985,7 @@ posix_test_lock(struct file *filp, struct file_lock *fl) void *owner; void (*func)(void); - ctx = smp_load_acquire(&inode->i_flctx); + ctx = locks_inode_context(inode); if (!ctx || list_empty_careful(&ctx->flc_posix)) { fl->fl_type = F_UNLCK; return; @@ -1577,7 +1577,7 @@ int __break_lease(struct inode *inode, unsigned int mode, unsigned int type) new_fl->fl_flags = type; /* typically we will check that ctx is non-NULL before calling */ - ctx = smp_load_acquire(&inode->i_flctx); + ctx = locks_inode_context(inode); if (!ctx) { WARN_ON_ONCE(1); goto free_lock; @@ -1682,7 +1682,7 @@ void lease_get_mtime(struct inode *inode, struct timespec64 *time) struct file_lock_context *ctx; struct file_lock *fl; - ctx = smp_load_acquire(&inode->i_flctx); + ctx = locks_inode_context(inode); if (ctx && !list_empty_careful(&ctx->flc_lease)) { spin_lock(&ctx->flc_lock); fl = list_first_entry_or_null(&ctx->flc_lease, @@ -1728,7 +1728,7 @@ int fcntl_getlease(struct file *filp) int type = F_UNLCK; LIST_HEAD(dispose); - ctx = smp_load_acquire(&inode->i_flctx); + ctx = locks_inode_context(inode); if (ctx && !list_empty_careful(&ctx->flc_lease)) { percpu_down_read(&file_rwsem); spin_lock(&ctx->flc_lock); @@ -1917,7 +1917,7 @@ static int generic_delete_lease(struct file *filp, void *owner) struct file_lock_context *ctx; LIST_HEAD(dispose); - ctx = smp_load_acquire(&inode->i_flctx); + ctx = locks_inode_context(inode); if (!ctx) { trace_generic_delete_lease(inode, NULL); return error; @@ -2651,7 +2651,7 @@ void locks_remove_posix(struct file *filp, fl_owner_t owner) * posix_lock_file(). Another process could be setting a lock on this * file at the same time, but we wouldn't remove that lock anyway. */ - ctx = smp_load_acquire(&inode->i_flctx); + ctx = locks_inode_context(inode); if (!ctx || list_empty(&ctx->flc_posix)) return; @@ -2724,7 +2724,7 @@ void locks_remove_file(struct file *filp) { struct file_lock_context *ctx; - ctx = smp_load_acquire(&locks_inode(filp)->i_flctx); + ctx = locks_inode_context(locks_inode(filp)); if (!ctx) return; @@ -2771,7 +2771,7 @@ bool vfs_inode_has_locks(struct inode *inode) struct file_lock_context *ctx; bool ret; - ctx = smp_load_acquire(&inode->i_flctx); + ctx = locks_inode_context(inode); if (!ctx) return false; @@ -2962,7 +2962,7 @@ void show_fd_locks(struct seq_file *f, struct file_lock_context *ctx; int id = 0; - ctx = smp_load_acquire(&inode->i_flctx); + ctx = locks_inode_context(inode); if (!ctx) return; diff --git a/include/linux/fs.h b/include/linux/fs.h index ef5a04d626953..61e86502fe65e 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1217,6 +1217,13 @@ extern void show_fd_locks(struct seq_file *f, struct file *filp, struct files_struct *files); extern bool locks_owner_has_blockers(struct file_lock_context *flctx, fl_owner_t owner); + +static inline struct file_lock_context * +locks_inode_context(const struct inode *inode) +{ + return smp_load_acquire(&inode->i_flctx); +} + #else /* !CONFIG_FILE_LOCKING */ static inline int fcntl_getlk(struct file *file, unsigned int cmd, struct flock __user *user) @@ -1362,6 +1369,13 @@ static inline bool locks_owner_has_blockers(struct file_lock_context *flctx, { return false; } + +static inline struct file_lock_context * +locks_inode_context(const struct inode *inode) +{ + return NULL; +} + #endif /* !CONFIG_FILE_LOCKING */ static inline struct inode *file_inode(const struct file *f) -- 2.43.0