ksmbd: use locks_inode_context helper

jtlayton · jtlayton · commit 87f00aba211e · 2022-11-30T05:08:10.000-05:00
ksmbd currently doesn't access i_flctx safely. This requires a
smp_load_acquire, as the pointer is set via cmpxchg (a release
operation).

Cc: Steve French &lt;sfrench@samba.org&gt;
Acked-by: Namjae Jeon &lt;linkinjeon@kernel.org&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Signed-off-by: Jeff Layton &lt;jlayton@kernel.org&gt;
diff --git a/fs/ksmbd/vfs.c b/fs/ksmbd/vfs.c
@@ -321,7 +321,7 @@ static int check_lock_range(struct file *filp, loff_t start, loff_t end,
 			    unsigned char type)
 {
 	struct file_lock *flock;
-	struct file_lock_context *ctx = file_inode(filp)->i_flctx;
+	struct file_lock_context *ctx = locks_inode_context(file_inode(filp));
 	int error = 0;
 
 	if (!ctx || list_empty_careful(&ctx->flc_posix))

Original file line number	Diff line number	Diff line change
`@@ -321,7 +321,7 @@ static int check_lock_range(struct file *filp, loff_t start, loff_t end,`
`321`	`321`	`unsigned char type)`
`322`	`322`	`{`
`323`	`323`	`struct file_lock *flock;`
`324`		`- struct file_lock_context *ctx = file_inode(filp)->i_flctx;`
	`324`	`+ struct file_lock_context *ctx = locks_inode_context(file_inode(filp));`
`325`	`325`	`int error = 0;`
`326`	`326`
`327`	`327`	`if (!ctx \|\| list_empty_careful(&ctx->flc_posix))`