mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-05 02:19:51 +00:00
No description
![]() copy_file_range tries to use the OSD 'copy-from' operation, which simply performs a full object copy. Unfortunately, the implementation of this system call assumes that stripe_count is always set to 1 and doesn't take into account that the data may be striped across an object set. If the file layout has stripe_count different from 1, then the destination file data will be corrupted. For example: Consider a 8 MiB file with 4 MiB object size, stripe_count of 2 and stripe_size of 2 MiB; the first half of the file will be filled with 'A's and the second half will be filled with 'B's: 0 4M 8M Obj1 Obj2 +------+------+ +----+ +----+ file: | AAAA | BBBB | | AA | | AA | +------+------+ |----| |----| | BB | | BB | +----+ +----+ If we copy_file_range this file into a new file (which needs to have the same file layout!), then it will start by copying the object starting at file offset 0 (Obj1). And then it will copy the object starting at file offset 4M -- which is Obj1 again. Unfortunately, the solution for this is to not allow remote object copies to be performed when the file layout stripe_count is not 1 and simply fallback to the default (VFS) copy_file_range implementation. Cc: stable@vger.kernel.org Signed-off-by: Luis Henriques <lhenriques@suse.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> |
||
---|---|---|
arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
LICENSES | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
Linux kernel ============ There are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. Please read Documentation/admin-guide/README.rst first. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. The formatted documentation can also be read online at: https://www.kernel.org/doc/html/latest/ There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.