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Subject[PATCH] exfat: Fix pontential use after free in exfat_load_upcase_table()
This code calls brelse(bh) and then dereferences "bh" on the next line
resulting in a possible use after free. The brelse() should just be
moved down a line.

Fixes: b676fdbcf4c8 ("exfat: standardize checksum calculation")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
fs/exfat/nls.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/exfat/nls.c b/fs/exfat/nls.c
index c1ec056954974..57b5a7a4d1f7a 100644
--- a/fs/exfat/nls.c
+++ b/fs/exfat/nls.c
@@ -692,8 +692,8 @@ static int exfat_load_upcase_table(struct super_block *sb,
index++;
}
}
- brelse(bh);
chksum = exfat_calc_chksum32(bh->b_data, i, chksum, CS_DEFAULT);
+ brelse(bh);
}

if (index >= 0xFFFF && utbl_checksum == chksum)
--
2.26.2
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