From 025b11465d086c55948eff484f40c993f2184990 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= <thomas@t-8ch.de>
Date: Fri, 12 Jan 2024 08:47:50 +0100
Subject: [PATCH] libblkid: avoid aligning out of probing area
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When reading from the end of the device the IO size alignment could
enlarge the read buffer outside of the probing area.
This would then trigger a read failure.

Signed-off-by: Thomas Weißschuh <thomas@t-8ch.de>
Reference:https://github.com/util-linux/util-linux/commit/025b11465d086c55948eff484f40c993f2184990
Conflict:Context adapt
---
 libblkid/src/probe.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/libblkid/src/probe.c b/libblkid/src/probe.c
index fee5b55..0e716b5 100644
--- a/libblkid/src/probe.c
+++ b/libblkid/src/probe.c
@@ -648,13 +648,18 @@ static int hide_buffer(blkid_probe pr, uint64_t off, uint64_t len)
 unsigned char *blkid_probe_get_buffer(blkid_probe pr, uint64_t off, uint64_t len)
 {
 	struct blkid_bufinfo *bf = NULL;
-	uint64_t real_off, bias;
+	uint64_t real_off, bias, len_align;
 
 	bias = off % pr->io_size;
 	off -= bias;
 	len += bias;
-	if (len % pr->io_size)
-		len += pr->io_size - (len % pr->io_size);
+
+	if (len % pr->io_size) {
+		len_align = pr->io_size - (len % pr->io_size);
+
+	if (pr->off + off + len + len_align <= pr->size)
+			len += len_align;
+	}
 
 	real_off = pr->off + off;
 
-- 
2.33.0

