From b96f465035f9fae83c1d8de3e80eecfe6877608c Mon Sep 17 00:00:00 2001 From: David Teigland Date: Tue, 25 Aug 2015 12:51:44 -0500 Subject: [PATCH] dlm: fix lvb copy for user locks For a userland lock request, the previous and current lock modes are used to decide when the lvb should be copied back to the user. The wrong previous value was used, so that it always matched the current value. This caused the lvb to be copied back to the user in the wrong cases. Signed-off-by: David Teigland --- fs/dlm/user.c | 7 ++++--- include/uapi/linux/dlm_device.h | 2 +- 2 files changed, 5 insertions(+), 4 deletions(-) diff --git a/fs/dlm/user.c b/fs/dlm/user.c index fb85f32e9eca..35960502ec8d 100644 --- a/fs/dlm/user.c +++ b/fs/dlm/user.c @@ -785,6 +785,7 @@ static ssize_t device_read(struct file *file, char __user *buf, size_t count, DECLARE_WAITQUEUE(wait, current); struct dlm_callback cb; int rv, resid, copy_lvb = 0; + int old_mode, new_mode; if (count == sizeof(struct dlm_device_version)) { rv = copy_version_to_user(buf, count); @@ -841,6 +842,9 @@ static ssize_t device_read(struct file *file, char __user *buf, size_t count, lkb = list_entry(proc->asts.next, struct dlm_lkb, lkb_cb_list); + /* rem_lkb_callback sets a new lkb_last_cast */ + old_mode = lkb->lkb_last_cast.mode; + rv = dlm_rem_lkb_callback(lkb->lkb_resource->res_ls, lkb, &cb, &resid); if (rv < 0) { /* this shouldn't happen; lkb should have been removed from @@ -864,9 +868,6 @@ static ssize_t device_read(struct file *file, char __user *buf, size_t count, } if (cb.flags & DLM_CB_CAST) { - int old_mode, new_mode; - - old_mode = lkb->lkb_last_cast.mode; new_mode = cb.mode; if (!cb.sb_status && lkb->lkb_lksb->sb_lvbptr && diff --git a/include/uapi/linux/dlm_device.h b/include/uapi/linux/dlm_device.h index 3060783c4191..df56c8ff0769 100644 --- a/include/uapi/linux/dlm_device.h +++ b/include/uapi/linux/dlm_device.h @@ -26,7 +26,7 @@ /* Version of the device interface */ #define DLM_DEVICE_VERSION_MAJOR 6 #define DLM_DEVICE_VERSION_MINOR 0 -#define DLM_DEVICE_VERSION_PATCH 1 +#define DLM_DEVICE_VERSION_PATCH 2 /* struct passed to the lock write */ struct dlm_lock_params { -- 2.34.1