On Fri, Oct 04, 2024 at 02:16:31PM -0400, Sasha Levin wrote:
From: Pankaj Raghav p.raghav@samsung.com
[ Upstream commit 10553a91652d995274da63fc317470f703765081 ]
iomap_dio_zero() will pad a fs block with zeroes if the direct IO size < fs block size. iomap_dio_zero() has an implicit assumption that fs block size < page_size. This is true for most filesystems at the moment.
If the block size > page size, this will send the contents of the page next to zero page(as len > PAGE_SIZE) to the underlying block device, causing FS corruption.
iomap is a generic infrastructure and it should not make any assumptions about the fs block size and the page size of the system.
Signed-off-by: Pankaj Raghav p.raghav@samsung.com Link: https://lore.kernel.org/r/20240822135018.1931258-7-kernel@pankajraghav.com Reviewed-by: Hannes Reinecke hare@suse.de Reviewed-by: Darrick J. Wong djwong@kernel.org Reviewed-by: Dave Chinner dchinner@redhat.com Reviewed-by: Daniel Gomez da.gomez@samsung.com Signed-off-by: Christian Brauner brauner@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org
fs/iomap/buffered-io.c | 4 ++-- fs/iomap/direct-io.c | 45 ++++++++++++++++++++++++++++++++++++------ 2 files changed, 41 insertions(+), 8 deletions(-)
For the second time: NACK to this patch for -all- LTS kernels.
It is a support patch for a new feature introduced in 6.12-rc1 - it is *not* a bug fix, it is not in any way relevant to LTS kernels, and it will *break some architectures* as it stands.
-Dave.