Message ID | 20230308041252.GC860405@mit.edu |
---|---|
State | Not Applicable |
Headers | show |
Series | ext4: swap i_disksize when swaping the boot loader inode | expand |
Hi Ted, > The following patch fixes the reported issue. > >>From f4e156cef119f3ffcc56874da4fb9299cc14f68e Mon Sep 17 00:00:00 2001 > From: Theodore Ts'o <tytso@mit.edu> > Date: Tue, 7 Mar 2023 23:06:59 -0500 > Subject: [PATCH] ext4: swap i_disksize when swaping the boot loader inode > > Normally well-behaved of EXT4_IOC_SWAP_BOOT won't actually try to > write to the either inode after using the ioctl, but if they do, the > fact that we're not swapping ei->i_disksize as well as inode->i_size > can trigger warnings. > > Link: https://bugzilla.kernel.org/show_bug.cgi?id=217159 > Signed-off-by: Theodore Ts'o <tytso@mit.edu> > --- > fs/ext4/ioctl.c | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) > > diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c > index 2e8c34036313..e552c5db0c95 100644 > --- a/fs/ext4/ioctl.c > +++ b/fs/ext4/ioctl.c > @@ -329,9 +329,13 @@ static void swap_inode_data(struct inode *inode1, struct inode *inode2) Shall we drop the redundant assignments 'swap(ei1->i_disksize, ei2->i_disksize);' ? > ext4_es_remove_extent(inode1, 0, EXT_MAX_BLOCKS); > ext4_es_remove_extent(inode2, 0, EXT_MAX_BLOCKS); > > - isize = i_size_read(inode1); > - i_size_write(inode1, i_size_read(inode2)); > - i_size_write(inode2, isize); > + /* > + * Both inodes are locked, so we don't need to fool around > + * with i_size_read() and i_size_write(). > + */ > + isize = inode1->i_size; > + inode1->i_size = ei1->i_disksize = inode2->i_size; > + inode2->i_size = ei2->i_disksize = isize; > } > > void ext4_reset_inode_seed(struct inode *inode) >
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index 2e8c34036313..e552c5db0c95 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -329,9 +329,13 @@ static void swap_inode_data(struct inode *inode1, struct inode *inode2) ext4_es_remove_extent(inode1, 0, EXT_MAX_BLOCKS); ext4_es_remove_extent(inode2, 0, EXT_MAX_BLOCKS); - isize = i_size_read(inode1); - i_size_write(inode1, i_size_read(inode2)); - i_size_write(inode2, isize); + /* + * Both inodes are locked, so we don't need to fool around + * with i_size_read() and i_size_write(). + */ + isize = inode1->i_size; + inode1->i_size = ei1->i_disksize = inode2->i_size; + inode2->i_size = ei2->i_disksize = isize; } void ext4_reset_inode_seed(struct inode *inode)