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exfat: resolve memory leak from exfat_create_upcase_table()

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If exfat_load_upcase_table reaches end and returns -EINVAL,
allocated memory doesn't get freed and while
exfat_load_default_upcase_table allocates more memory, leading to a
memory leak.

Here's link to syzkaller crash report illustrating this issue:
https://syzkaller.appspot.com/text?tag=CrashReport&x=1406c201980000

Reported-by: syzbot+e1c69cadec0f1a078e3d@syzkaller.appspotmail.com
Fixes: a13d1a4de3 ("exfat: move freeing sbi, upcase table and dropping nls into rcu-delayed helper")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Yang <danielyangkang@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
This commit is contained in:
Daniel Yang 2024-09-16 16:05:06 -07:00 committed by Namjae Jeon
parent 6630ea4910
commit c290fe508e
1 changed files with 4 additions and 1 deletions
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5
fs/exfat/nls.c
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@ -779,8 +779,11 @@ int exfat_create_upcase_table(struct super_block *sb)
le32_to_cpu(ep->dentry.upcase.checksum));
brelse(bh);
if (ret && ret != -EIO)
if (ret && ret != -EIO) {
/* free memory from exfat_load_upcase_table call */
exfat_free_upcase_table(sbi);
goto load_default;
}
/* load successfully */
return ret;