Store the cookie to detect concurrent seeks on directories in
file->private_data.
Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
---
fs/proc/base.c | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 72a1acd03675..8a8aab6b9801 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -3870,12 +3870,12 @@ static int proc_task_readdir(struct file *file, struct dir_context *ctx)
if (!dir_emit_dots(file, ctx))
return 0;
- /* f_version caches the tgid value that the last readdir call couldn't
- * return. lseek aka telldir automagically resets f_version to 0.
+ /* We cache the tgid value that the last readdir call couldn't
+ * return and lseek resets it to 0.
*/
ns = proc_pid_ns(inode->i_sb);
- tid = (int)file->f_version;
- file->f_version = 0;
+ tid = (int)(intptr_t)file->private_data;
+ file->private_data = NULL;
for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns);
task;
task = next_tid(task), ctx->pos++) {
@@ -3890,7 +3890,7 @@ static int proc_task_readdir(struct file *file, struct dir_context *ctx)
proc_task_instantiate, task, NULL)) {
/* returning this tgid failed, save it as the first
* pid for the next readir call */
- file->f_version = (u64)tid;
+ file->private_data = (void *)(intptr_t)tid;
put_task_struct(task);
break;
}
@@ -3915,6 +3915,12 @@ static int proc_task_getattr(struct mnt_idmap *idmap,
return 0;
}
+static loff_t proc_dir_llseek(struct file *file, loff_t offset, int whence)
+{
+ return generic_llseek_cookie(file, offset, whence,
+ (u64 *)(uintptr_t)&file->private_data);
+}
+
static const struct inode_operations proc_task_inode_operations = {
.lookup = proc_task_lookup,
.getattr = proc_task_getattr,
@@ -3925,7 +3931,7 @@ static const struct inode_operations proc_task_inode_operations = {
static const struct file_operations proc_task_operations = {
.read = generic_read_dir,
.iterate_shared = proc_task_readdir,
- .llseek = generic_file_llseek,
+ .llseek = proc_dir_llseek,
};
void __init set_proc_pid_nlink(void)
--
2.45.2
