From a.velichayshiy at ispras.ru  Sat Nov  1 12:55:27 2025
From: a.velichayshiy at ispras.ru (Alexey Velichayshiy)
Date: Sat,  1 Nov 2025 12:55:27 +0300
Subject: [lvc-project] [PATCH] gfs2: eliminate unreachable code in
	gfs2_freeze_super()
Message-ID: <20251101095554.6130-1-a.velichayshiy@ispras.ru>

The general error check after gfs2_do_thaw() made the subsequent
specific error handlers for -EBUSY and -EIO unreachable. Remove
the redundant general check to ensure proper error handling
for specific cases while preserving the retry mechanism.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Alexey Velichayshiy <a.velichayshiy at ispras.ru>
---
 fs/gfs2/super.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index 644b2d1e7276..03b407a925dc 100644
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -750,8 +750,6 @@ static int gfs2_freeze_super(struct super_block *sb, enum freeze_holder who,
 		}
 
 		error = gfs2_do_thaw(sdp, who, freeze_owner);
-		if (error)
-			goto out;
 
 		if (error == -EBUSY)
 			fs_err(sdp, "waiting for recovery before freeze\n");
-- 
2.43.0



From pchelkin at ispras.ru  Sat Nov  1 19:04:28 2025
From: pchelkin at ispras.ru (Fedor Pchelkin)
Date: Sat,  1 Nov 2025 19:04:28 +0300
Subject: [lvc-project] [PATCH v2 1/2] ext4: fix string copying in
	parse_apply_sb_mount_options()
Message-ID: <20251101160430.222297-1-pchelkin@ispras.ru>

strscpy_pad() can't be used to copy a non-NUL-term string into a NUL-term
string of possibly bigger size.  Commit 0efc5990bca5 ("string.h: Introduce
memtostr() and memtostr_pad()") provides additional information in that
regard.  So if this happens, the following warning is observed:

strnlen: detected buffer overflow: 65 byte read of buffer size 64
WARNING: CPU: 0 PID: 28655 at lib/string_helpers.c:1032 __fortify_report+0x96/0xc0 lib/string_helpers.c:1032
Modules linked in:
CPU: 0 UID: 0 PID: 28655 Comm: syz-executor.3 Not tainted 6.12.54-syzkaller-00144-g5f0270f1ba00 #0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:__fortify_report+0x96/0xc0 lib/string_helpers.c:1032
Call Trace:
 <TASK>
 __fortify_panic+0x1f/0x30 lib/string_helpers.c:1039
 strnlen include/linux/fortify-string.h:235 [inline]
 sized_strscpy include/linux/fortify-string.h:309 [inline]
 parse_apply_sb_mount_options fs/ext4/super.c:2504 [inline]
 __ext4_fill_super fs/ext4/super.c:5261 [inline]
 ext4_fill_super+0x3c35/0xad00 fs/ext4/super.c:5706
 get_tree_bdev_flags+0x387/0x620 fs/super.c:1636
 vfs_get_tree+0x93/0x380 fs/super.c:1814
 do_new_mount fs/namespace.c:3553 [inline]
 path_mount+0x6ae/0x1f70 fs/namespace.c:3880
 do_mount fs/namespace.c:3893 [inline]
 __do_sys_mount fs/namespace.c:4103 [inline]
 __se_sys_mount fs/namespace.c:4080 [inline]
 __x64_sys_mount+0x280/0x300 fs/namespace.c:4080
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x64/0x140 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Since userspace is expected to provide s_mount_opts field to be at most 63
characters long with the ending byte being NUL-term, use a 64-byte buffer
which matches the size of s_mount_opts, so that strscpy_pad() does its job
properly.  Return with error if the user still managed to provide a
non-NUL-term string here.

Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

Fixes: 8ecb790ea8c3 ("ext4: avoid potential buffer over-read in parse_apply_sb_mount_options()")
Cc: stable at vger.kernel.org
Signed-off-by: Fedor Pchelkin <pchelkin at ispras.ru>
---

v2: - treat non-NUL-term s_mount_opts as invalid case (Jan Kara)
    - swap order of patches in series so the fixing-one goes first

v1: https://lore.kernel.org/lkml/20251028130949.599847-1-pchelkin at ispras.ru/T/#u

 fs/ext4/super.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 33e7c08c9529..15bef41f08bd 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -2475,7 +2475,7 @@ static int parse_apply_sb_mount_options(struct super_block *sb,
 					struct ext4_fs_context *m_ctx)
 {
 	struct ext4_sb_info *sbi = EXT4_SB(sb);
-	char s_mount_opts[65];
+	char s_mount_opts[64];
 	struct ext4_fs_context *s_ctx = NULL;
 	struct fs_context *fc = NULL;
 	int ret = -ENOMEM;
@@ -2483,7 +2483,8 @@ static int parse_apply_sb_mount_options(struct super_block *sb,
 	if (!sbi->s_es->s_mount_opts[0])
 		return 0;
 
-	strscpy_pad(s_mount_opts, sbi->s_es->s_mount_opts);
+	if (strscpy_pad(s_mount_opts, sbi->s_es->s_mount_opts) < 0)
+		return -E2BIG;
 
 	fc = kzalloc(sizeof(struct fs_context), GFP_KERNEL);
 	if (!fc)
-- 
2.51.0



From pchelkin at ispras.ru  Sat Nov  1 19:04:29 2025
From: pchelkin at ispras.ru (Fedor Pchelkin)
Date: Sat,  1 Nov 2025 19:04:29 +0300
Subject: [lvc-project] [PATCH v2 2/2] ext4: check if mount_opts is
	NUL-terminated in ext4_ioctl_set_tune_sb()
In-Reply-To: <20251101160430.222297-1-pchelkin@ispras.ru>
References: <20251101160430.222297-1-pchelkin@ispras.ru>
Message-ID: <20251101160430.222297-2-pchelkin@ispras.ru>

params.mount_opts may come as potentially non-NUL-term string.  Userspace
is expected to pass a NUL-term string.  Add an extra check to ensure this
holds true.  Note that further code utilizes strscpy_pad() so this is just
for proper informing the user of incorrect data being provided.

Found by Linux Verification Center (linuxtesting.org).

Signed-off-by: Fedor Pchelkin <pchelkin at ispras.ru>
---

v2: check length of mount_opts in superblock tuning ioctl (Jan Kara)

    Can't plainly return error at strscpy_pad() call site in
    ext4_sb_setparams(), that's a void ext4_update_sb_callback.

v1: https://lore.kernel.org/lkml/20251028130949.599847-1-pchelkin at ispras.ru/T/#u

 fs/ext4/ioctl.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index a93a7baae990..3dec26c939fd 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -1394,6 +1394,10 @@ static int ext4_ioctl_set_tune_sb(struct file *filp,
 	if (copy_from_user(&params, in, sizeof(params)))
 		return -EFAULT;
 
+	if (strnlen(params.mount_opts, sizeof(params.mount_opts)) ==
+	    sizeof(params.mount_opts))
+		return -E2BIG;
+
 	if ((params.set_flags & ~TUNE_OPS_SUPPORTED) != 0)
 		return -EOPNOTSUPP;
 
-- 
2.51.0



From pchelkin at ispras.ru  Sun Nov  2 17:12:50 2025
From: pchelkin at ispras.ru (Fedor Pchelkin)
Date: Sun, 2 Nov 2025 17:12:50 +0300
Subject: [lvc-project] [PATCH 5.10/5.15/6.1/6.6] vxlan: Fix NPD in {arp,
 neigh}_reduce() when using nexthop objects
In-Reply-To: <20251030192907.406431-1-kovalev@altlinux.org>
References: <20251030192907.406431-1-kovalev@altlinux.org>
Message-ID: <20251102170752-60f7844a80fe5d16cc31e7cd-pchelkin@ispras>

On Thu, 30. Oct 22:29, Vasiliy Kovalev wrote:
> Link: https://patch.msgid.link/20250901065035.159644-3-idosch at nvidia.com

?? ???? ?????? ?????? ?????? ???? ??? ??????????? ??? CVE-2025-39851,
?????????? ??? ??? ?? ?????.  ????????????? ????????? ? ??.

????? ??????????????? ???????? ??? ??????? ?????????? ????? ????
804b09be09f8 ("vxlan: Add RCU read-side critical sections in the Tx path").
????? ???????, ????? ?? ????? ??? ??????????.

> Signed-off-by: Jakub Kicinski <kuba at kernel.org>
> [ kovalev: bp to fix CVE-2025-39850 ]
> Signed-off-by: Vasiliy Kovalev <kovalev at altlinux.org>