This is a note to let you know that I've just added the patch titled
f2fs: explicitly null-terminate the xattr list
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
f2fs-explicitly-null-terminate-the-xattr-list.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From e26b6d39270f5eab0087453d9b544189a38c8564 Mon Sep 17 00:00:00 2001
From: Eric Biggers <ebiggers@xxxxxxxxxx>
Date: Mon, 6 Nov 2023 20:44:34 -0800
Subject: f2fs: explicitly null-terminate the xattr list
From: Eric Biggers <ebiggers@xxxxxxxxxx>
commit e26b6d39270f5eab0087453d9b544189a38c8564 upstream.
When setting an xattr, explicitly null-terminate the xattr list. This
eliminates the fragile assumption that the unused xattr space is always
zeroed.
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Reviewed-by: Chao Yu <chao@xxxxxxxxxx>
Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/f2fs/xattr.c | 6 ++++++
1 file changed, 6 insertions(+)
--- a/fs/f2fs/xattr.c
+++ b/fs/f2fs/xattr.c
@@ -717,6 +717,12 @@ static int __f2fs_setxattr(struct inode
memcpy(pval, value, size);
last->e_value_size = cpu_to_le16(size);
new_hsize += newsize;
+ /*
+ * Explicitly add the null terminator. The unused xattr space
+ * is supposed to always be zeroed, which would make this
+ * unnecessary, but don't depend on that.
+ */
+ *(u32 *)((u8 *)last + newsize) = 0;
}
error = write_all_xattrs(inode, new_hsize, base_addr, ipage);
Patches currently in stable-queue which might be from ebiggers@xxxxxxxxxx are
queue-4.19/f2fs-explicitly-null-terminate-the-xattr-list.patch
