mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-04-18 16:08:10 -04:00
dd862da61e
A recent commit introduced nfs4_do_mkdir() which reports an error from
nfs4_call_sync() by returning it with ERR_PTR().
This is a problem as nfs4_call_sync() can return negative NFS-specific
errors with values larger than MAX_ERRNO (4095). One example is
NFS4ERR_DELAY which has value 10008.
This "pointer" gets to PTR_ERR_OR_ZERO() in nfs4_proc_mkdir() which
chooses ZERO because it isn't in the range of value errors. Ultimately
the pointer is dereferenced.
This patch changes nfs4_do_mkdir() to report the dentry pointer and
status separately - pointer as a return value, status in an "int *"
parameter.
The same separation is used for _nfs4_proc_mkdir() and the two are
combined only in nfs4_proc_mkdir() after the status has passed through
nfs4_handle_exception(), which ensures the error code does not exceed
MAX_ERRNO.
It also fixes a problem in the even when nfs4_handle_exception() updated
the error value, the original 'alias' was still returned.
Reported-by: Anna Schumaker <anna@kernel.org>
Fixes: 8376583b84 ("nfs: change mkdir inode_operation to return alternate dentry if needed.")
Signed-off-by: NeilBrown <neil@brown.name>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.