FAILED: patch "[PATCH] udf: Make sure there's enough space for LVID implementation use field" failed to apply to 5.15-stable tree

FAILED: patch "[PATCH] udf: Make sure there's enough space for LVID implementation use field" failed to apply to 5.15-stable tree

[Sasha Levin]

The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x a61fb39759d719a4f4966742b4d28387e33d81c4
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '20261107055724-failed-5.15-a61fb39759d7@kernel.org' --subject-prefix 'PATCH 5.15.y' 'HEAD^..'

Thanks,
Sasha

------------------ original commit in Linus's tree ------------------

From a61fb39759d719a4f4966742b4d28387e33d81c4 Mon Sep 17 00:00:00 2001
From: Jan Kara <jack@suse.cz>
Date: Mon, 31 Aug 2026 11:17:14 +0200
Subject: [PATCH] udf: Make sure there's enough space for LVID implementation
 use field

udf_lvid_valid() verifies that the LVID has enough space for all the
tables and the reported length of ImplementationUse field. However it
doesn't make sure the reported length is large enough to contain
logicalVolIntegrityDescImpUse structure which OSTA specification
requires. This can thus lead to accesses beyond the end of LVID buffer
for suitably corrupted UDF filesystem. Add the length check.

Reported-by: Yunpeng Tian <shionthanatos@gmail.com>
Reported-by: Gongming Wang <gmwgg05@gmail.com>
Reported-by: Mingda Zhang <npczmd@qq.com>
Reported-by: Qinrun Dai <jupmouse@gmail.com>
Cc: stable@vger.kernel.org
Fixes: 781d2a9a2fc7 ("udf: Check LVID earlier")
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/udf/super.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/udf/super.c b/fs/udf/super.c
index 2ba5973ef4dd4..5351755aca3ec 100644
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -1617,7 +1617,10 @@ static bool udf_lvid_valid(struct super_block *sb,
 
 	parts = le32_to_cpu(lvid->numOfPartitions);
 	impuselen = le32_to_cpu(lvid->lengthOfImpUse);
-	if (parts >= sb->s_blocksize || impuselen >= sb->s_blocksize ||
+	if (sizeof(struct logicalVolIntegrityDescImpUse) > impuselen ||
+	    impuselen >= sb->s_blocksize)
+		return false;
+	if (parts >= sb->s_blocksize ||
 	    sizeof(struct logicalVolIntegrityDesc) + impuselen +
 	    2 * parts * sizeof(u32) > sb->s_blocksize)
 		return false;
-- 
2.53.0

[PATCH 5.15.y 1/2] udf: Avoid invalid LVID used on mount

[Sasha Levin]

From: Jan Kara <jack@suse.cz>

[ Upstream commit c8f1140cb82dc843e72697dc6f8c7ee1acce5d28 ]

udf_load_logicalvolint() loads logical volume integrity descriptors.
Since there can be multiple blocks with LVIDs, we verify the contents of
only the last (prevailing) LVID found. However if we fail to load the
last LVID (either due to IO error or because it's checksum fails to
match), we never perform the verification of validity of the LVID we are
going to use. If such LVID contains invalid data, we can hit
out-of-bounds access or similar issues. Fix the problem by verifying
each LVID we are potentially going to accept.

Reported-by: Robert Morris <rtm@csail.mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Stable-dep-of: a61fb39759d7 ("udf: Make sure there's enough space for LVID implementation use field")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/udf/super.c | 42 +++++++++++++++++++++++++-----------------
 1 file changed, 25 insertions(+), 17 deletions(-)

diff --git a/fs/udf/super.c b/fs/udf/super.c
index afdc0f50a5f00..f9fe3f950de85 100644
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -1575,6 +1575,20 @@ static int udf_load_logicalvol(struct super_block *sb, sector_t block,
 	return ret;
 }
 
+static bool udf_lvid_valid(struct super_block *sb,
+			   struct logicalVolIntegrityDesc *lvid)
+{
+	u32 parts, impuselen;
+
+	parts = le32_to_cpu(lvid->numOfPartitions);
+	impuselen = le32_to_cpu(lvid->lengthOfImpUse);
+	if (parts >= sb->s_blocksize || impuselen >= sb->s_blocksize ||
+	    sizeof(struct logicalVolIntegrityDesc) + impuselen +
+	    2 * parts * sizeof(u32) > sb->s_blocksize)
+		return false;
+	return true;
+}
+
 /*
  * Find the prevailing Logical Volume Integrity Descriptor.
  */
@@ -1585,7 +1599,6 @@ static void udf_load_logicalvolint(struct super_block *sb, struct kernel_extent_
 	struct udf_sb_info *sbi = UDF_SB(sb);
 	struct logicalVolIntegrityDesc *lvid;
 	int indirections = 0;
-	u32 parts, impuselen;
 
 	while (++indirections <= UDF_MAX_LVID_NESTING) {
 		final_bh = NULL;
@@ -1607,32 +1620,27 @@ static void udf_load_logicalvolint(struct super_block *sb, struct kernel_extent_
 		if (!final_bh)
 			return;
 
-		brelse(sbi->s_lvid_bh);
-		sbi->s_lvid_bh = final_bh;
-
 		lvid = (struct logicalVolIntegrityDesc *)final_bh->b_data;
+		if (udf_lvid_valid(sb, lvid)) {
+			brelse(sbi->s_lvid_bh);
+			sbi->s_lvid_bh = final_bh;
+		} else {
+			udf_warn(sb, "Corrupted LVID (parts=%u, impuselen=%u), "
+				 "ignoring.\n",
+				 le32_to_cpu(lvid->numOfPartitions),
+				 le32_to_cpu(lvid->lengthOfImpUse));
+		}
+
 		if (lvid->nextIntegrityExt.extLength == 0)
-			goto check;
+			return;
 
 		loc = leea_to_cpu(lvid->nextIntegrityExt);
 	}
 
 	udf_warn(sb, "Too many LVID indirections (max %u), ignoring.\n",
 		UDF_MAX_LVID_NESTING);
-out_err:
 	brelse(sbi->s_lvid_bh);
 	sbi->s_lvid_bh = NULL;
-	return;
-check:
-	parts = le32_to_cpu(lvid->numOfPartitions);
-	impuselen = le32_to_cpu(lvid->lengthOfImpUse);
-	if (parts >= sb->s_blocksize || impuselen >= sb->s_blocksize ||
-	    sizeof(struct logicalVolIntegrityDesc) + impuselen +
-	    2 * parts * sizeof(u32) > sb->s_blocksize) {
-		udf_warn(sb, "Corrupted LVID (parts=%u, impuselen=%u), "
-			 "ignoring.\n", parts, impuselen);
-		goto out_err;
-	}
 }
 
 /*
-- 
2.53.0

[PATCH 5.15.y 2/2] udf: Make sure there's enough space for LVID implementation use field

[Sasha Levin]

From: Jan Kara <jack@suse.cz>

[ Upstream commit a61fb39759d719a4f4966742b4d28387e33d81c4 ]

udf_lvid_valid() verifies that the LVID has enough space for all the
tables and the reported length of ImplementationUse field. However it
doesn't make sure the reported length is large enough to contain
logicalVolIntegrityDescImpUse structure which OSTA specification
requires. This can thus lead to accesses beyond the end of LVID buffer
for suitably corrupted UDF filesystem. Add the length check.

Reported-by: Yunpeng Tian <shionthanatos@gmail.com>
Reported-by: Gongming Wang <gmwgg05@gmail.com>
Reported-by: Mingda Zhang <npczmd@qq.com>
Reported-by: Qinrun Dai <jupmouse@gmail.com>
Cc: stable@vger.kernel.org
Fixes: 781d2a9a2fc7 ("udf: Check LVID earlier")
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/udf/super.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/udf/super.c b/fs/udf/super.c
index f9fe3f950de85..6857c15f5a0f4 100644
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -1582,7 +1582,10 @@ static bool udf_lvid_valid(struct super_block *sb,
 
 	parts = le32_to_cpu(lvid->numOfPartitions);
 	impuselen = le32_to_cpu(lvid->lengthOfImpUse);
-	if (parts >= sb->s_blocksize || impuselen >= sb->s_blocksize ||
+	if (sizeof(struct logicalVolIntegrityDescImpUse) > impuselen ||
+	    impuselen >= sb->s_blocksize)
+		return false;
+	if (parts >= sb->s_blocksize ||
 	    sizeof(struct logicalVolIntegrityDesc) + impuselen +
 	    2 * parts * sizeof(u32) > sb->s_blocksize)
 		return false;
-- 
2.53.0