From: Tony Dinh <mibodhi@gmail.com>
Date: Fri, 23 May 2025 05:02:01 +0000 (-0700)
Subject: ext4fs: Fix: Read outside partition error
X-Git-Tag: v2025.07-rc3~3
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=df2ed552f0b05591090369a7fe7ddc92439dea5c;p=pandora-u-boot.git

ext4fs: Fix: Read outside partition error

Use lbaint_t for blknr to avoid overflow in ext4fs_read_file().

Background:

blknr (block number) used in ext4fs_read_file() could be increased to a
very large value and causes a wrap around at 32 bit signed integer max,
thus becomes negative. This results in an out-of-normal range for sector
number (during the assignment delayed_start = blknr) where delayed_start
sector is typed uint64 lbaint_t. This causes the "Read outside partition"
error.

This patch was tested on the Synology DS116 (Armada 385) board, and a
4TB Seagate HDD.

Signed-off-by: Tony Dinh <mibodhi@gmail.com>
---

diff --git a/fs/ext4/ext4fs.c b/fs/ext4/ext4fs.c
index 1727da2dc6d..f10c622e62c 100644
--- a/fs/ext4/ext4fs.c
+++ b/fs/ext4/ext4fs.c
@@ -101,7 +101,7 @@ int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
 	blockcnt = lldiv(((len + pos) + blocksize - 1), blocksize);
 
 	for (i = lldiv(pos, blocksize); i < blockcnt; i++) {
-		long int blknr;
+		lbaint_t blknr;
 		int blockoff = pos - (blocksize * i);
 		int blockend = blocksize;
 		int skipfirst = 0;