From: Yuto Ohnuki <ytohnuki@amazon.com>
Date: Mon, 23 Feb 2026 12:33:46 +0000 (+0000)
Subject: ext4: replace BUG_ON with proper error handling in ext4_read_inline_folio
X-Git-Tag: v7.0-rc6~12^2~19
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=356227096eb66e41b23caf7045e6304877322edf;p=thirdparty%2Flinux.git

ext4: replace BUG_ON with proper error handling in ext4_read_inline_folio

Replace BUG_ON() with proper error handling when inline data size
exceeds PAGE_SIZE. This prevents kernel panic and allows the system to
continue running while properly reporting the filesystem corruption.

The error is logged via ext4_error_inode(), the buffer head is released
to prevent memory leak, and -EFSCORRUPTED is returned to indicate
filesystem corruption.

Signed-off-by: Yuto Ohnuki <ytohnuki@amazon.com>
Link: https://patch.msgid.link/20260223123345.14838-2-ytohnuki@amazon.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
---

diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
index 1f6bc05593df..408677fa8196 100644
--- a/fs/ext4/inline.c
+++ b/fs/ext4/inline.c
@@ -522,7 +522,15 @@ static int ext4_read_inline_folio(struct inode *inode, struct folio *folio)
 		goto out;
 
 	len = min_t(size_t, ext4_get_inline_size(inode), i_size_read(inode));
-	BUG_ON(len > PAGE_SIZE);
+
+	if (len > PAGE_SIZE) {
+		ext4_error_inode(inode, __func__, __LINE__, 0,
+				 "inline size %zu exceeds PAGE_SIZE", len);
+		ret = -EFSCORRUPTED;
+		brelse(iloc.bh);
+		goto out;
+	}
+
 	kaddr = kmap_local_folio(folio, 0);
 	ret = ext4_read_inline_data(inode, kaddr, len, &iloc);
 	kaddr = folio_zero_tail(folio, len, kaddr + len);