loop: revert exclusive opener loop status change

This commit effectively reverts the following two commits:

2704024d83fa ("loop: add missing bd_abort_claiming in loop_set_status")
08e136ebd193 ("loop: don't change loop device under exclusive opener in loop_set_status")

as there are reports of them causing issues with unmounting. As we're
close to the 6.19 kernel release and the original author hasn't taken a
closer look at this yet, revert them for release.

Reported-by: nokangaroo <nokangaroo@aon.at>
Link: https://lore.kernel.org/all/62de4453-17e8-47f6-a10b-39bf5a49fdee@leemhuis.info/
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index bd59c0e9508b729942e501ec02983dce4e6828fe..32a3a5b138029e65e97f331fb64577ceedbdf59c 100644 (file)
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -1225,28 +1225,16 @@ static int loop_clr_fd(struct loop_device *lo)
 }
 
 static int
-loop_set_status(struct loop_device *lo, blk_mode_t mode,
-               struct block_device *bdev, const struct loop_info64 *info)
+loop_set_status(struct loop_device *lo, const struct loop_info64 *info)
 {
        int err;
        bool partscan = false;
        bool size_changed = false;
        unsigned int memflags;
 
-       /*
-        * If we don't hold exclusive handle for the device, upgrade to it
-        * here to avoid changing device under exclusive owner.
-        */
-       if (!(mode & BLK_OPEN_EXCL)) {
-               err = bd_prepare_to_claim(bdev, loop_set_status, NULL);
-               if (err)
-                       goto out_reread_partitions;
-       }
-
        err = mutex_lock_killable(&lo->lo_mutex);
        if (err)
-               goto out_abort_claiming;
-
+               return err;
        if (lo->lo_state != Lo_bound) {
                err = -ENXIO;
                goto out_unlock;
@@ -1285,10 +1273,6 @@ out_unfreeze:
        }
 out_unlock:
        mutex_unlock(&lo->lo_mutex);
-out_abort_claiming:
-       if (!(mode & BLK_OPEN_EXCL))
-               bd_abort_claiming(bdev, loop_set_status);
-out_reread_partitions:
        if (partscan)
                loop_reread_partitions(lo);
 
@@ -1368,9 +1352,7 @@ loop_info64_to_old(const struct loop_info64 *info64, struct loop_info *info)
 }
 
 static int
-loop_set_status_old(struct loop_device *lo, blk_mode_t mode,
-                   struct block_device *bdev,
-                   const struct loop_info __user *arg)
+loop_set_status_old(struct loop_device *lo, const struct loop_info __user *arg)
 {
        struct loop_info info;
        struct loop_info64 info64;
@@ -1378,19 +1360,17 @@ loop_set_status_old(struct loop_device *lo, blk_mode_t mode,
        if (copy_from_user(&info, arg, sizeof (struct loop_info)))
                return -EFAULT;
        loop_info64_from_old(&info, &info64);
-       return loop_set_status(lo, mode, bdev, &info64);
+       return loop_set_status(lo, &info64);
 }
 
 static int
-loop_set_status64(struct loop_device *lo, blk_mode_t mode,
-                 struct block_device *bdev,
-                 const struct loop_info64 __user *arg)
+loop_set_status64(struct loop_device *lo, const struct loop_info64 __user *arg)
 {
        struct loop_info64 info64;
 
        if (copy_from_user(&info64, arg, sizeof (struct loop_info64)))
                return -EFAULT;
-       return loop_set_status(lo, mode, bdev, &info64);
+       return loop_set_status(lo, &info64);
 }
 
 static int
@@ -1569,14 +1549,14 @@ static int lo_ioctl(struct block_device *bdev, blk_mode_t mode,
        case LOOP_SET_STATUS:
                err = -EPERM;
                if ((mode & BLK_OPEN_WRITE) || capable(CAP_SYS_ADMIN))
-                       err = loop_set_status_old(lo, mode, bdev, argp);
+                       err = loop_set_status_old(lo, argp);
                break;
        case LOOP_GET_STATUS:
                return loop_get_status_old(lo, argp);
        case LOOP_SET_STATUS64:
                err = -EPERM;
                if ((mode & BLK_OPEN_WRITE) || capable(CAP_SYS_ADMIN))
-                       err = loop_set_status64(lo, mode, bdev, argp);
+                       err = loop_set_status64(lo, argp);
                break;
        case LOOP_GET_STATUS64:
                return loop_get_status64(lo, argp);
@@ -1670,9 +1650,8 @@ loop_info64_to_compat(const struct loop_info64 *info64,
 }
 
 static int
-loop_set_status_compat(struct loop_device *lo, blk_mode_t mode,
-                   struct block_device *bdev,
-                   const struct compat_loop_info __user *arg)
+loop_set_status_compat(struct loop_device *lo,
+                      const struct compat_loop_info __user *arg)
 {
        struct loop_info64 info64;
        int ret;
@@ -1680,7 +1659,7 @@ loop_set_status_compat(struct loop_device *lo, blk_mode_t mode,
        ret = loop_info64_from_compat(arg, &info64);
        if (ret < 0)
                return ret;
-       return loop_set_status(lo, mode, bdev, &info64);
+       return loop_set_status(lo, &info64);
 }
 
 static int
@@ -1706,7 +1685,7 @@ static int lo_compat_ioctl(struct block_device *bdev, blk_mode_t mode,
 
        switch(cmd) {
        case LOOP_SET_STATUS:
-               err = loop_set_status_compat(lo, mode, bdev,
+               err = loop_set_status_compat(lo,
                             (const struct compat_loop_info __user *)arg);
                break;
        case LOOP_GET_STATUS: