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| author | Matthew Wilcox (Oracle) <willy@infradead.org> | 2020-01-17 23:45:12 +0100 |
|---|---|---|
| committer | Matthew Wilcox (Oracle) <willy@infradead.org> | 2020-01-18 04:32:24 +0100 |
| commit | 430f24f94c8a174d411a550d7b5529301922e67a (patch) | |
| tree | 7a23f31ee6f3bca6a09e1ce0c23fa62d4e65c5e1 /lib/xarray.c | |
| parent | XArray: Add wrappers for nested spinlocks (diff) | |
| download | linux-430f24f94c8a174d411a550d7b5529301922e67a.tar.xz linux-430f24f94c8a174d411a550d7b5529301922e67a.zip | |
XArray: Fix infinite loop with entry at ULONG_MAX
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
Diffstat (limited to 'lib/xarray.c')
| -rw-r--r-- | lib/xarray.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/lib/xarray.c b/lib/xarray.c index bfaaa2c1f3fe..6ecf35c2e1da 100644 --- a/lib/xarray.c +++ b/lib/xarray.c @@ -1849,6 +1849,9 @@ void *xa_find_after(struct xarray *xa, unsigned long *indexp, XA_STATE(xas, xa, *indexp + 1); void *entry; + if (xas.xa_index == 0) + return NULL; + rcu_read_lock(); for (;;) { if ((__force unsigned int)filter < XA_MAX_MARKS) |