author: Christian Brauner <christian.brauner@ubuntu.com> 2021-04-02 10:29:36 +0200
committer: Christian Brauner <christian.brauner@ubuntu.com> 2021-04-02 14:11:10 +0200
commit: 9b5b872215fe6d1ca6a1ef411f130bd58e269012
parent: 0d02ec6b3136c73c09e7859f0d0e4e2c4c07b49b
Commit Summary:
Diffstat:
1 file changed, 17 insertions, 4 deletions
diff --git a/fs/file.c b/fs/file.c
index f3a4bac2cbe9..f633348029a5 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -629,17 +629,30 @@ int close_fd(unsigned fd)
}
EXPORT_SYMBOL(close_fd); /* for ksys_close() */
+/**
+ * last_fd - return last valid index into fd table
+ * @cur_fds: files struct
+ *
+ * Context: Either rcu read lock or files_lock must be held.
+ *
+ * Returns: Last valid index into fdtable.
+ */
+static inline unsigned last_fd(struct fdtable *fdt)
+{
+ return fdt->max_fds - 1;
+}
+
static inline void __range_cloexec(struct files_struct *cur_fds,
unsigned int fd, unsigned int max_fd)
{
struct fdtable *fdt;
- if (fd > max_fd)
- return;
-
+ /* make sure we're using the correct maximum value */
spin_lock(&cur_fds->file_lock);
fdt = files_fdtable(cur_fds);
- bitmap_set(fdt->close_on_exec, fd, max_fd - fd + 1);
+ max_fd = min(last_fd(fdt), max_fd);
+ if (fd <= max_fd)
+ bitmap_set(fdt->close_on_exec, fd, max_fd - fd + 1);
spin_unlock(&cur_fds->file_lock);
}