linux-kernel - Re: [syzbot] Re: general protection fault in exfat_get_dentry

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Message-ID: <675bed89.050a0220.cd16f.0042.GAE@google.com>
Date: Fri, 13 Dec 2024 00:17:13 -0800
From: syzbot <syzbot+8f8fe64a30c50b289a18@...kaller.appspotmail.com>
To: linux-kernel@...r.kernel.org, syzkaller-bugs@...glegroups.com
Subject: Re: [syzbot] Re: general protection fault in exfat_get_dentry_cached()

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Subject: Re: general protection fault in exfat_get_dentry_cached()
Author: dmantipov@...dex.ru

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git f932fb9b40749d1c9a539d89bb3e288c077aafe5

diff --git a/fs/exfat/namei.c b/fs/exfat/namei.c
index 97d2774760fe..c356bde623bf 100644
--- a/fs/exfat/namei.c
+++ b/fs/exfat/namei.c
@@ -329,10 +329,7 @@ static int exfat_find_empty_entry(struct inode *inode,
 			EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags);
 
 	while ((dentry = exfat_search_empty_slot(sb, &hint_femp, p_dir,
-					num_entries, es)) < 0) {
-		if (dentry == -EIO)
-			break;
-
+					num_entries, es)) == -ENOSPC) {
 		if (exfat_check_max_dentries(inode))
 			return -ENOSPC;
 
@@ -395,6 +392,9 @@ static int exfat_find_empty_entry(struct inode *inode,
 		inode->i_blocks += sbi->cluster_size >> 9;
 	}
 
+	if (dentry < 0)
+		return dentry;
+
 	p_dir->dir = exfat_sector_to_cluster(sbi, es->bh[0]->b_blocknr);
 	p_dir->size -= dentry / sbi->dentries_per_clu;