From: Tejun Heo Date: Sun, 20 Apr 2014 12:29:21 +0000 (-0400) Subject: kernfs: add back missing error check in kernfs_fop_mmap() X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=b44b2140265ddfde03acbe809336111d31adb0d1;p=openwrt%2Fstaging%2Fblogic.git kernfs: add back missing error check in kernfs_fop_mmap() While updating how mmap enabled kernfs files are handled by lockdep, 9b2db6e18945 ("sysfs: bail early from kernfs_file_mmap() to avoid spurious lockdep warning") inadvertently dropped error return check from kernfs_file_mmap(). The intention was just dropping "if (ops->mmap)" check as the control won't reach the point if the mmap callback isn't implemented, but I mistakenly removed the error return check together with it. This led to Xorg crash on i810 which was reported and bisected to the commit and then to the specific change by Tobias. Signed-off-by: Tejun Heo Reported-and-bisected-by: Tobias Powalowski Tested-by: Tobias Powalowski References: http://lkml.kernel.org/g/533D01BD.1010200@googlemail.com Cc: stable # 3.14 Signed-off-by: Greg Kroah-Hartman --- diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c index 8034706a7af8..e01ea4a14a01 100644 --- a/fs/kernfs/file.c +++ b/fs/kernfs/file.c @@ -484,6 +484,8 @@ static int kernfs_fop_mmap(struct file *file, struct vm_area_struct *vma) ops = kernfs_ops(of->kn); rc = ops->mmap(of, vma); + if (rc) + goto out_put; /* * PowerPC's pci_mmap of legacy_mem uses shmem_zero_setup()