This is a note to let you know that I've just added the patch titled btrfs: fix btrfs_compat_ioctl failures on non-compat ioctls to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: btrfs-fix-btrfs_compat_ioctl-failures-on-non-compat-ioctls.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 2a362249187a8d0f6d942d6e1d763d150a296f47 Mon Sep 17 00:00:00 2001 From: Jeff Mahoney <jeffm@xxxxxxxx> Date: Mon, 6 Feb 2017 19:39:09 -0500 Subject: btrfs: fix btrfs_compat_ioctl failures on non-compat ioctls From: Jeff Mahoney <jeffm@xxxxxxxx> commit 2a362249187a8d0f6d942d6e1d763d150a296f47 upstream. Commit 4c63c2454ef incorrectly assumed that returning -ENOIOCTLCMD would cause the native ioctl to be called. The ->compat_ioctl callback is expected to handle all ioctls, not just compat variants. As a result, when using 32-bit userspace on 64-bit kernels, everything except those three ioctls would return -ENOTTY. Fixes: 4c63c2454ef ("btrfs: bugfix: handle FS_IOC32_{GETFLAGS,SETFLAGS,GETVERSION} in btrfs_ioctl") Signed-off-by: Jeff Mahoney <jeffm@xxxxxxxx> Reviewed-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/btrfs/ioctl.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -5648,6 +5648,10 @@ long btrfs_ioctl(struct file *file, unsi #ifdef CONFIG_COMPAT long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { + /* + * These all access 32-bit values anyway so no further + * handling is necessary. + */ switch (cmd) { case FS_IOC32_GETFLAGS: cmd = FS_IOC_GETFLAGS; @@ -5658,8 +5662,6 @@ long btrfs_compat_ioctl(struct file *fil case FS_IOC32_GETVERSION: cmd = FS_IOC_GETVERSION; break; - default: - return -ENOIOCTLCMD; } return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg)); Patches currently in stable-queue which might be from jeffm@xxxxxxxx are queue-4.9/btrfs-fix-btrfs_compat_ioctl-failures-on-non-compat-ioctls.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html