Commit 16ae3132 authored Nov 06, 2023 by Eric Biggers Committed by Greg Kroah-Hartman Jan 25, 2024

f2fs: explicitly null-terminate the xattr list



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@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent abc2dd6a

fs/f2fs/xattr.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -717,6 +717,12 @@ static int __f2fs_setxattr(struct inode *inode, int index,
		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);