Patch "staging: android: ashmem: lseek failed due to no FMODE_LSEEK." has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

staging: android: ashmem: lseek failed due to no FMODE_LSEEK.

to the 4.4-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:
staging-android-ashmem-lseek-failed-due-to-no-fmode_lseek.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Shuxiao Zhang <[email protected]>
Date: Thu, 6 Apr 2017 22:30:29 +0800
Subject: staging: android: ashmem: lseek failed due to no FMODE_LSEEK.

From: Shuxiao Zhang <[email protected]>

commit 97fbfef6bd597888485b653175fb846c6998b60c upstream.

vfs_llseek will check whether the file mode has
FMODE_LSEEK, no return failure. But ashmem can be
lseek, so add FMODE_LSEEK to ashmem file.

Comment From Greg Hackmann:
ashmem_llseek() passes the llseek() call through to the backing shmem file. 91360b02ab48 ("ashmem: use vfs_llseek()") changed this from directly calling the file's llseek() op into a VFS layer call. This also adds a check for the FMODE_LSEEK bit, so without that bit ashmem_llseek() now always fails with -ESPIPE.

---
 drivers/staging/android/ashmem.c |    1 +
 1 file changed, 1 insertion(+)

@@ -392,6 +392,7 @@ static int ashmem_mmap(struct file *file
 			ret = PTR_ERR(vmfile);
 			goto out;
 		}
+		vmfile->f_mode |= FMODE_LSEEK;
 		asma->file = vmfile;
 	}
 	get_file(asma->file);

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/staging-android-ashmem-lseek-failed-due-to-no-fmode_lseek.patch