commit cac7ea57a06016e4914848b707477fb07ee4ae1c upstream.

Currently the pthread allocation for each array item is based on the size
of a pthread_t pointer and should be the size of the pthread_t structure,
so the allocation is under-allocating the correct size.  Fix this by using
the size of each element in the pthreads array.

Static analysis cppcheck reported:
tools/testing/radix-tree/regression1.c:180:2: warning: Size of pointer
'threads' used instead of size of its data. [pointerSize]

Link: https://lkml.kernel.org/r/20230727160930.632674-1-colin.i.king@gmail.com
Fixes: 1366c37ed84b ("radix tree test harness")
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 5c089fd0c73411f2170ab795c9ffc16718c7d007 upstream.

If the entry is deleted from the IDR between the call to
radix_tree_iter_find() and rcu_dereference_raw(), idr_get_next()
will return NULL, which will end the iteration prematurely.  We should
instead continue to the next entry in the IDR.  This only happens if the
iteration is protected by the RCU lock.  Most IDR users use a spinlock
or semaphore to exclude simultaneous modifications.  It was noticed once
the PID allocator was converted to use the IDR, as it uses the RCU lock,
but there may be other users elsewhere in the kernel.

We can't use the normal pattern of calling radix_tree_deref_retry()
(which catches both a retry entry in a leaf node and a node entry in
the root) as the IDR supports storing entries which are unaligned,
which will trigger an infinite loop if they are encountered.  Instead,
we have to explicitly check whether the entry is a retry entry.

Fixes: 0a835c4f090a ("Reimplement IDR and IDA using the radix tree")
Reported-by: Brendan Gregg <bgregg@netflix.com>
Tested-by: Brendan Gregg <bgregg@netflix.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Move these tests from the userspace test-suite to the kernel test-suite.
Also convert check_ida_random to the new API.

Signed-off-by: Matthew Wilcox <willy@infradead.org>

Move as much as possible to kernel space; leave the parts in user space
that rely on checking memory allocation failures to detect the
transition between an exceptional entry and a bitmap.

Signed-off-by: Matthew Wilcox <willy@infradead.org>

Convert to new API and move to kernel space.

Signed-off-by: Matthew Wilcox <willy@infradead.org>

Convert to new API and move to kernel space.  Take the opportunity to
test the situation a little more thoroughly (ie at different offsets).

Signed-off-by: Matthew Wilcox <willy@infradead.org>

We can't move this test to kernel space because there's no way to
force kmalloc to fail.  But we can use the new API and check this
works when the test is in userspace.

Signed-off-by: Matthew Wilcox <willy@infradead.org>

Start transitioning the IDA tests into kernel space.  Framework heavily
cribbed from test_xarray.c.

Signed-off-by: Matthew Wilcox <willy@infradead.org>

Add support for the undefined behaviour sanitizer and fix the bugs
that ubsan pointed out.  Nothing major, and all in the test suite,
not the code.

Signed-off-by: Matthew Wilcox <willy@infradead.org>

An include of xarray.h was added to lib/idr.c without updating the test
suite.

Signed-off-by: Matthew Wilcox <willy@infradead.org>