| Message ID | 20200304170646.GA31552@dumbo (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | [v2] hibernate: Allow uswsusp to write to swap | expand |
On Wednesday, March 4, 2020 6:06:46 PM CET Domenico Andreoli wrote: > From: Domenico Andreoli <domenico.andreoli@linux.com> > > It turns out that there is one use case for programs being able to > write to swap devices, and that is the userspace hibernation code. > > Quick fix: disable the S_SWAPFILE check if hibernation is configured. > > Fixes: dc617f29dbe5 ("vfs: don't allow writes to swap files") > Reported-by: Domenico Andreoli <domenico.andreoli@linux.com> > Reported-by: Marian Klein <mkleinsoft@gmail.com> > Signed-off-by: Domenico Andreoli <domenico.andreoli@linux.com> > > v2: > - use hibernation_available() instead of IS_ENABLED(CONFIG_HIBERNATE) > - make Fixes: point to the right commit This looks OK to me. Has it been taken care of already, or am I expected to apply it? > --- > fs/block_dev.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > Index: b/fs/block_dev.c > =================================================================== > --- a/fs/block_dev.c > +++ b/fs/block_dev.c > @@ -34,6 +34,7 @@ > #include <linux/task_io_accounting_ops.h> > #include <linux/falloc.h> > #include <linux/uaccess.h> > +#include <linux/suspend.h> > #include "internal.h" > > struct bdev_inode { > @@ -2001,7 +2002,8 @@ ssize_t blkdev_write_iter(struct kiocb * > if (bdev_read_only(I_BDEV(bd_inode))) > return -EPERM; > > - if (IS_SWAPFILE(bd_inode)) > + /* uswsusp needs write permission to the swap */ > + if (IS_SWAPFILE(bd_inode) && !hibernation_available()) > return -ETXTBSY; > > if (!iov_iter_count(from)) >
On Sun, Mar 22, 2020 at 08:14:21AM +0100, Rafael J. Wysocki wrote: > On Wednesday, March 4, 2020 6:06:46 PM CET Domenico Andreoli wrote: > > From: Domenico Andreoli <domenico.andreoli@linux.com> > > > > It turns out that there is one use case for programs being able to > > write to swap devices, and that is the userspace hibernation code. > > > > Quick fix: disable the S_SWAPFILE check if hibernation is configured. > > > > Fixes: dc617f29dbe5 ("vfs: don't allow writes to swap files") > > Reported-by: Domenico Andreoli <domenico.andreoli@linux.com> > > Reported-by: Marian Klein <mkleinsoft@gmail.com> > > Signed-off-by: Domenico Andreoli <domenico.andreoli@linux.com> > > > > v2: > > - use hibernation_available() instead of IS_ENABLED(CONFIG_HIBERNATE) > > - make Fixes: point to the right commit > > This looks OK to me. > > Has it been taken care of already, or am I expected to apply it? I don't know who is supposed to take it, I did not receive any notification. > > > --- > > fs/block_dev.c | 4 +++- > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > Index: b/fs/block_dev.c > > =================================================================== > > --- a/fs/block_dev.c > > +++ b/fs/block_dev.c > > @@ -34,6 +34,7 @@ > > #include <linux/task_io_accounting_ops.h> > > #include <linux/falloc.h> > > #include <linux/uaccess.h> > > +#include <linux/suspend.h> > > #include "internal.h" > > > > struct bdev_inode { > > @@ -2001,7 +2002,8 @@ ssize_t blkdev_write_iter(struct kiocb * > > if (bdev_read_only(I_BDEV(bd_inode))) > > return -EPERM; > > > > - if (IS_SWAPFILE(bd_inode)) > > + /* uswsusp needs write permission to the swap */ > > + if (IS_SWAPFILE(bd_inode) && !hibernation_available()) > > return -ETXTBSY; > > > > if (!iov_iter_count(from)) > > > > > >
On Sun, Mar 22, 2020 at 12:23:14PM +0100, Domenico Andreoli wrote: > On Sun, Mar 22, 2020 at 08:14:21AM +0100, Rafael J. Wysocki wrote: > > On Wednesday, March 4, 2020 6:06:46 PM CET Domenico Andreoli wrote: > > > From: Domenico Andreoli <domenico.andreoli@linux.com> > > > > > > It turns out that there is one use case for programs being able to > > > write to swap devices, and that is the userspace hibernation code. > > > > > > Quick fix: disable the S_SWAPFILE check if hibernation is configured. > > > > > > Fixes: dc617f29dbe5 ("vfs: don't allow writes to swap files") > > > Reported-by: Domenico Andreoli <domenico.andreoli@linux.com> > > > Reported-by: Marian Klein <mkleinsoft@gmail.com> > > > Signed-off-by: Domenico Andreoli <domenico.andreoli@linux.com> > > > > > > v2: > > > - use hibernation_available() instead of IS_ENABLED(CONFIG_HIBERNATE) > > > - make Fixes: point to the right commit > > > > This looks OK to me. > > > > Has it been taken care of already, or am I expected to apply it? > > I don't know who is supposed to take it, I did not receive any notification. Hmmm. I thought it had been picked up by akpm (see "[alternative-merged] vfs-partially-revert-dont-allow-writes-to-swap-files.patch removed from -mm tree" from 5 March), but it's not in mmotm now, so I'll put this in my vfs tree for 5.7. Also, since apparently my previous RVB apparently never made it to the internet, Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> --D > > > > > --- > > > fs/block_dev.c | 4 +++- > > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > > > Index: b/fs/block_dev.c > > > =================================================================== > > > --- a/fs/block_dev.c > > > +++ b/fs/block_dev.c > > > @@ -34,6 +34,7 @@ > > > #include <linux/task_io_accounting_ops.h> > > > #include <linux/falloc.h> > > > #include <linux/uaccess.h> > > > +#include <linux/suspend.h> > > > #include "internal.h" > > > > > > struct bdev_inode { > > > @@ -2001,7 +2002,8 @@ ssize_t blkdev_write_iter(struct kiocb * > > > if (bdev_read_only(I_BDEV(bd_inode))) > > > return -EPERM; > > > > > > - if (IS_SWAPFILE(bd_inode)) > > > + /* uswsusp needs write permission to the swap */ > > > + if (IS_SWAPFILE(bd_inode) && !hibernation_available()) > > > return -ETXTBSY; > > > > > > if (!iov_iter_count(from)) > > > > > > > > > > > > > -- > rsa4096: 3B10 0CA1 8674 ACBA B4FE FCD2 CE5B CF17 9960 DE13 > ed25519: FFB4 0CC3 7F2E 091D F7DA 356E CC79 2832 ED38 CB05
On Mon, 23 Mar 2020 08:21:05 -0700 "Darrick J. Wong" <darrick.wong@oracle.com> wrote: > > > Has it been taken care of already, or am I expected to apply it? > > > > I don't know who is supposed to take it, I did not receive any notification. > > Hmmm. I thought it had been picked up by akpm (see "[alternative-merged] > vfs-partially-revert-dont-allow-writes-to-swap-files.patch removed from > -mm tree" from 5 March), but it's not in mmotm now, oop. Things which are advertised as "hibernate: ..." tend not to survive my morning email triage :( > so I'll put this in my > vfs tree for 5.7. Thanks. But I assume that "it turns out that userspace hibernation requires the ability to write the hibernation image to a swap device" means we've regressed userspace hibernation. So I'd say either "5.6 with a cc:stable" or "5.7-rc1 with a cc:stable" if we're being more cautious.
Index: b/fs/block_dev.c =================================================================== --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -34,6 +34,7 @@ #include <linux/task_io_accounting_ops.h> #include <linux/falloc.h> #include <linux/uaccess.h> +#include <linux/suspend.h> #include "internal.h" struct bdev_inode { @@ -2001,7 +2002,8 @@ ssize_t blkdev_write_iter(struct kiocb * if (bdev_read_only(I_BDEV(bd_inode))) return -EPERM; - if (IS_SWAPFILE(bd_inode)) + /* uswsusp needs write permission to the swap */ + if (IS_SWAPFILE(bd_inode) && !hibernation_available()) return -ETXTBSY; if (!iov_iter_count(from))