diff options
author | Matthew Wilcox (Oracle) <willy@infradead.org> | 2020-01-17 17:45:12 -0500 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-01-29 16:45:26 +0100 |
commit | a5135ca1f92a7b201b7f8297f42b8579f92bc55d (patch) | |
tree | 186501e471fdb0e5e845e9bddb03e5144d1c3051 /lib/test_xarray.c | |
parent | b8560e3d90afad8c5ee1ae4fea41949a76b5bb8b (diff) |
XArray: Fix infinite loop with entry at ULONG_MAX
commit 430f24f94c8a174d411a550d7b5529301922e67a upstream.
If there is an entry at ULONG_MAX, xa_for_each() will overflow the
'index + 1' in xa_find_after() and wrap around to 0. Catch this case
and terminate the loop by returning NULL.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'lib/test_xarray.c')
-rw-r--r-- | lib/test_xarray.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/lib/test_xarray.c b/lib/test_xarray.c index 7df4f7f395bf..e8eaafeebb17 100644 --- a/lib/test_xarray.c +++ b/lib/test_xarray.c @@ -1046,11 +1046,28 @@ static noinline void check_find_3(struct xarray *xa) xa_destroy(xa); } +static noinline void check_find_4(struct xarray *xa) +{ + unsigned long index = 0; + void *entry; + + xa_store_index(xa, ULONG_MAX, GFP_KERNEL); + + entry = xa_find_after(xa, &index, ULONG_MAX, XA_PRESENT); + XA_BUG_ON(xa, entry != xa_mk_index(ULONG_MAX)); + + entry = xa_find_after(xa, &index, ULONG_MAX, XA_PRESENT); + XA_BUG_ON(xa, entry); + + xa_erase_index(xa, ULONG_MAX); +} + static noinline void check_find(struct xarray *xa) { check_find_1(xa); check_find_2(xa); check_find_3(xa); + check_find_4(xa); check_multi_find(xa); check_multi_find_2(xa); } |