09 Apr, 2019
1 commit
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In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.This patch fixes the following warnings:
fs/affs/affs.h:124:38: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/configfs/dir.c:1692:11: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/configfs/dir.c:1694:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ceph/file.c:249:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/hash.c:233:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/hash.c:246:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext2/inode.c:1237:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext2/inode.c:1244:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1182:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1188:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1432:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1440:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/f2fs/node.c:618:8: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/f2fs/node.c:620:8: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/btrfs/ref-verify.c:522:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/gfs2/bmap.c:711:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/gfs2/bmap.c:722:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/jffs2/fs.c:339:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/nfsd/nfs4proc.c:429:12: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ufs/util.h:62:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ufs/util.h:43:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/fcntl.c:770:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/seq_file.c:319:10: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/libfs.c:148:11: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/libfs.c:150:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/signalfd.c:178:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/locks.c:1473:16: warning: this statement may fall through [-Wimplicit-fallthrough=]Warning level 3 was used: -Wimplicit-fallthrough=3
This patch is part of the ongoing efforts to enabling
-Wimplicit-fallthrough.Reviewed-by: Kees Cook
Signed-off-by: Gustavo A. R. Silva
03 Oct, 2018
1 commit
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Linus recently observed that if we did not worry about the padding
member in struct siginfo it is only about 48 bytes, and 48 bytes is
much nicer than 128 bytes for allocating on the stack and copying
around in the kernel.The obvious thing of only adding the padding when userspace is
including siginfo.h won't work as there are sigframe definitions in
the kernel that embed struct siginfo.So split siginfo in two; kernel_siginfo and siginfo. Keeping the
traditional name for the userspace definition. While the version that
is used internally to the kernel and ultimately will not be padded to
128 bytes is called kernel_siginfo.The definition of struct kernel_siginfo I have put in include/signal_types.h
A set of buildtime checks has been added to verify the two structures have
the same field offsets.To make it easy to verify the change kernel_siginfo retains the same
size as siginfo. The reduction in size comes in a following change.Signed-off-by: "Eric W. Biederman"
16 Aug, 2018
1 commit
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Recently syzbot reported crashes in send_sigio_to_task and
send_sigurg_to_task in linux-next. Despite finding a reproducer
syzbot apparently did not bisected this or otherwise track down the
offending commit in linux-next.I happened to see this report and examined the code because I had
recently changed these functions as part of making PIDTYPE_TGID a real
pid type so that fork would does not need to restart when receiving a
signal. By examination I see that I spotted a bug in the code
that could explain the reported crashes.When I took Oleg's suggestion and optimized send_sigurg and send_sigio
to only send to a single task when type is PIDTYPE_PID or PIDTYPE_TGID
I failed to handle pids that no longer point to tasks. The macro
do_each_pid_task simply iterates for zero iterations. With pid_task
an explicit NULL test is needed.Update the code to include the missing NULL test.
Fixes: 019191342fec ("signal: Use PIDTYPE_TGID to clearly store where file signals will be sent")
Reported-by: syzkaller-bugs@googlegroups.com
Signed-off-by: "Eric W. Biederman"
22 Jul, 2018
2 commits
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This passes the information we already have at the call sight into
do_send_sig_info. Ultimately allowing for better handling of signals
sent to a group of processes during fork.Signed-off-by: "Eric W. Biederman"
-
This information is already present and using it directly simplifies the logic
of the code.Signed-off-by: "Eric W. Biederman"
21 Jul, 2018
1 commit
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When f_setown is called a pid and a pid type are stored. Replace the use
of PIDTYPE_PID with PIDTYPE_TGID as PIDTYPE_TGID goes to the entire thread
group. Replace the use of PIDTYPE_MAX with PIDTYPE_PID as PIDTYPE_PID now
is only for a thread.Update the users of __f_setown to use PIDTYPE_TGID instead of
PIDTYPE_PID.For now the code continues to capture task_pid (when task_tgid would
really be appropriate), and iterate on PIDTYPE_PID (even when type ==
PIDTYPE_TGID) out of an abundance of caution to preserve existing
behavior.Oleg Nesterov suggested using the test to ensure we use PIDTYPE_PID
for tgid lookup also be used to avoid taking the tasklist lock.Suggested-by: Oleg Nesterov
Signed-off-by: "Eric W. Biederman"
08 Jun, 2018
1 commit
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With the addition of memfd hugetlbfs support, we now have the situation
where memfd depends on TMPFS -or- HUGETLBFS. Previously, memfd was only
supported on tmpfs, so it made sense that the code resided in shmem.c.
In the current code, memfd is only functional if TMPFS is defined. If
HUGETLFS is defined and TMPFS is not defined, then memfd functionality
will not be available for hugetlbfs. This does not cause BUGs, just a
lack of potentially desired functionality.Code is restructured in the following way:
- include/linux/memfd.h is a new file containing memfd specific
definitions previously contained in shmem_fs.h.
- mm/memfd.c is a new file containing memfd specific code previously
contained in shmem.c.
- memfd specific code is removed from shmem_fs.h and shmem.c.
- A new config option MEMFD_CREATE is added that is defined if TMPFS
or HUGETLBFS is defined.No functional changes are made to the code: restructuring only.
Link: http://lkml.kernel.org/r/20180415182119.4517-4-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz
Reviewed-by: Khalid Aziz
Cc: Andrea Arcangeli
Cc: David Herrmann
Cc: Hugh Dickins
Cc: Marc-Andr Lureau
Cc: Matthew Wilcox
Cc: Michal Hocko
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
01 May, 2018
1 commit
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I observed the following deadlock between them:
[task 1] [task 2] [task 3]
kill_fasync() mm_update_next_owner() copy_process()
spin_lock_irqsave(&fa->fa_lock) read_lock(&tasklist_lock) write_lock_irq(&tasklist_lock)
send_sigio() ...
read_lock(&fown->lock) kill_fasync() ...
read_lock(&tasklist_lock) spin_lock_irqsave(&fa->fa_lock) ...Task 1 can't acquire read locked tasklist_lock, since there is
already task 3 expressed its wish to take the lock exclusive.
Task 2 holds the read locked lock, but it can't take the spin lock.Also, there is possible another deadlock (which I haven't observed):
[task 1] [task 2]
f_getown() kill_fasync()
read_lock(&f_own->lock) spin_lock_irqsave(&fa->fa_lock,)
send_sigio() write_lock_irq(&f_own->lock)
kill_fasync() read_lock(&fown->lock)
spin_lock_irqsave(&fa->fa_lock,)Actually, we do not need exclusive fa->fa_lock in kill_fasync_rcu(),
as it guarantees fa->fa_file->f_owner integrity only. It may seem,
that it used to give a task a small possibility to receive two sequential
signals, if there are two parallel kill_fasync() callers, and task
handles the first signal fastly, but the behaviour won't become
different, since there is exclusive sighand lock in do_send_sig_info().The patch converts fa_lock into rwlock_t, and this fixes two above
deadlocks, as rwlock is allowed to be taken from interrupt handler
by qrwlock design.Signed-off-by: Kirill Tkhai
Signed-off-by: Jeff Layton
03 Apr, 2018
1 commit
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Using the fs-internal do_compat_fcntl64() helper allows us to get rid of
the fs-internal call to the compat_sys_fcntl64() syscall.This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.netCc: Al Viro
Cc: Andrew Morton
Signed-off-by: Dominik Brodowski
12 Feb, 2018
2 commits
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This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
for f in $L; do sed -i "-es/^\([^\"]*\)\(\\)/\\1E\\2/" $f; done
donewith de-mangling cleanups yet to come.
NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do. But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.The next patch from Al will sort out the final differences, and we
should be all done.Scripted-by: Al Viro
Signed-off-by: Linus Torvalds -
Pull more poll annotation updates from Al Viro:
"This is preparation to solving the problems you've mentioned in the
original poll series.After this series, the kernel is ready for running
for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
for f in $L; do sed -i "-es/^\([^\"]*\)\(\\)/\\1E\\2/" $f; done
doneas a for bulk search-and-replace.
After that, the kernel is ready to apply the patch to unify
{de,}mangle_poll(), and then get rid of kernel-side POLL... uses
entirely, and we should be all done with that stuff.Basically, that's what you suggested wrt KPOLL..., except that we can
use EPOLL... instead - they already are arch-independent (and equal to
what is currently kernel-side POLL...).After the preparations (in this series) switch to returning EPOLL...
from ->poll() instances is completely mechanical and kernel-side
POLL... can go away. The last step (killing kernel-side POLL... and
unifying {de,}mangle_poll() has to be done after the
search-and-replace job, since we need userland-side POLL... for
unified {de,}mangle_poll(), thus the cherry-pick at the last step.After that we will have:
- POLL{IN,OUT,...} *not* in __poll_t, so any stray instances of
->poll() still using those will be caught by sparse.- eventpoll.c and select.c warning-free wrt __poll_t
- no more kernel-side definitions of POLL... - userland ones are
visible through the entire kernel (and used pretty much only for
mangle/demangle)- same behavior as after the first series (i.e. sparc et.al. epoll(2)
working correctly)"* 'work.poll2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
annotate ep_scan_ready_list()
ep_send_events_proc(): return result via esed->res
preparation to switching ->poll() to returning EPOLL...
add EPOLLNVAL, annotate EPOLL... and event_poll->event
use linux/poll.h instead of asm/poll.h
xen: fix poll misannotation
smc: missing poll annotations
02 Feb, 2018
1 commit
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The only place that has any business including asm/poll.h
is linux/poll.h. Fortunately, asm/poll.h had only been
included in 3 places beyond that one, and all of them
are trivial to switch to using linux/poll.h.Signed-off-by: Al Viro
01 Feb, 2018
1 commit
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Those functions are called for memfd files, backed by shmem or hugetlb
(the next patches will handle hugetlb).Link: http://lkml.kernel.org/r/20171107122800.25517-3-marcandre.lureau@redhat.com
Signed-off-by: Marc-André Lureau
Reviewed-by: Mike Kravetz
Cc: Andrea Arcangeli
Cc: Hugh Dickins
Cc: Michal Hocko
Cc: David Herrmann
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
31 Jan, 2018
1 commit
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Pull poll annotations from Al Viro:
"This introduces a __bitwise type for POLL### bitmap, and propagates
the annotations through the tree. Most of that stuff is as simple as
'make ->poll() instances return __poll_t and do the same to local
variables used to hold the future return value'.Some of the obvious brainos found in process are fixed (e.g. POLLIN
misspelled as POLL_IN). At that point the amount of sparse warnings is
low and most of them are for genuine bugs - e.g. ->poll() instance
deciding to return -EINVAL instead of a bitmap. I hadn't touched those
in this series - it's large enough as it is.Another problem it has caught was eventpoll() ABI mess; select.c and
eventpoll.c assumed that corresponding POLL### and EPOLL### were
equal. That's true for some, but not all of them - EPOLL### are
arch-independent, but POLL### are not.The last commit in this series separates userland POLL### values from
the (now arch-independent) kernel-side ones, converting between them
in the few places where they are copied to/from userland. AFAICS, this
is the least disruptive fix preserving poll(2) ABI and making epoll()
work on all architectures.As it is, it's simply broken on sparc - try to give it EPOLLWRNORM and
it will trigger only on what would've triggered EPOLLWRBAND on other
architectures. EPOLLWRBAND and EPOLLRDHUP, OTOH, are never triggered
at all on sparc. With this patch they should work consistently on all
architectures"* 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (37 commits)
make kernel-side POLL... arch-independent
eventpoll: no need to mask the result of epi_item_poll() again
eventpoll: constify struct epoll_event pointers
debugging printk in sg_poll() uses %x to print POLL... bitmap
annotate poll(2) guts
9p: untangle ->poll() mess
->si_band gets POLL... bitmap stored into a user-visible long field
ring_buffer_poll_wait() return value used as return value of ->poll()
the rest of drivers/*: annotate ->poll() instances
media: annotate ->poll() instances
fs: annotate ->poll() instances
ipc, kernel, mm: annotate ->poll() instances
net: annotate ->poll() instances
apparmor: annotate ->poll() instances
tomoyo: annotate ->poll() instances
sound: annotate ->poll() instances
acpi: annotate ->poll() instances
crypto: annotate ->poll() instances
block: annotate ->poll() instances
x86: annotate ->poll() instances
...
13 Jan, 2018
1 commit
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Call clear_siginfo to ensure stack allocated siginfos are fully
initialized before being passed to the signal sending functions.This ensures that if there is the kind of confusion documented by
TRAP_FIXME, FPE_FIXME, or BUS_FIXME the kernel won't send unitialized
data to userspace when the kernel generates a signal with SI_USER but
the copy to userspace assumes it is a different kind of signal, and
different fields are initialized.This also prepares the way for turning copy_siginfo_to_user
into a copy_to_user, by removing the need in many cases to perform
a field by field copy simply to skip the uninitialized fields.Signed-off-by: "Eric W. Biederman"
30 Nov, 2017
1 commit
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mangle/demangle on the way to/from userland
Signed-off-by: Al Viro
29 Nov, 2017
1 commit
-
Signed-off-by: Al Viro
15 Nov, 2017
2 commits
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Currently, we're capping the values too low in the F_GETLK64 case. The
fields in that structure are 64-bit values, so we shouldn't need to do
any sort of fixup there.Make sure we check that assumption at build time in the future however
by ensuring that the sizes we're copying will fit.With this, we no longer need COMPAT_LOFF_T_MAX either, so remove it.
Fixes: 94073ad77fff2 (fs/locks: don't mess with the address limit in compat_fcntl64)
Reported-by: Vitaly Lipatov
Signed-off-by: Jeff Layton
Reviewed-by: David Howells -
Currently we just return err here, but we need to put the fd reference
first.Fixes: 94073ad77fff (fs/locks: don't mess with the address limit in compat_fcntl64)
Signed-off-by: Jeff Layton
07 Nov, 2017
1 commit
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Conflicts:
include/linux/compiler-clang.h
include/linux/compiler-gcc.h
include/linux/compiler-intel.h
include/uapi/linux/stddef.hSigned-off-by: Ingo Molnar
02 Nov, 2017
1 commit
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Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.By default all files without license information are under the default
license of the kernel, which is GPL version 2.Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if
Reviewed-by: Philippe Ombredanne
Reviewed-by: Thomas Gleixner
Signed-off-by: Greg Kroah-Hartman
25 Oct, 2017
1 commit
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…READ_ONCE()/WRITE_ONCE()
Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch
virtual patch
@ depends on patch @
expression E1, E2;
@@- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)@ depends on patch @
expression E;
@@- ACCESS_ONCE(E)
+ READ_ONCE(E)
----Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
19 Sep, 2017
1 commit
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When fixing things to avoid ambiguous cases I had a thinko
and included SIGPOLL/SIGIO in with all of the other signals
that have signal specific si_codes. Which is completely wrong.Fix that.
Reported-by: Vince Weaver
Signed-off-by: "Eric W. Biederman"
25 Jul, 2017
1 commit
-
We have a weird and problematic intersection of features that when
they all come together result in ambiguous siginfo values, that
we can not support properly.- Supporting fcntl(F_SETSIG,...) with arbitrary valid signals.
- Using positive values for POLL_IN, POLL_OUT, POLL_MSG, ..., etc
that imply they are signal specific si_codes and using the
aforementioned arbitrary signal to deliver them.- Supporting injection of arbitrary siginfo values for debugging and
checkpoint/restore.The result is that just looking at siginfo si_codes of 1 to 6 are
ambigious. It could either be a signal specific si_code or it could
be a generic si_code.For most of the kernel this is a non-issue but for sending signals
with siginfo it is impossible to play back the kernel signals and
get the same result.Strictly speaking when the si_code was changed from SI_SIGIO to
POLL_IN and friends between 2.2 and 2.4 this functionality was not
ambiguous, as only real time signals were supported. Before 2.4 was
released the kernel began supporting siginfo with non realtime signals
so they could give details of why the signal was sent.The result is that if F_SETSIG is set to one of the signals with signal
specific si_codes then user space can not know why the signal was sent.I grepped through a bunch of userspace programs using debian code
search to get a feel for how often people choose a signal that results
in an ambiguous si_code. I only found one program doing so and it was
using SIGCHLD to test the F_SETSIG functionality, and did not appear
to be a real world usage.Therefore the ambiguity does not appears to be a real world problem in
practice. Remove the ambiguity while introducing the smallest chance
of breakage by changing the si_code to SI_SIGIO when signals with
signal specific si_codes are targeted.Fixes: v2.3.40 -- Added support for queueing non-rt signals
Fixes: v2.3.21 -- Changed the si_code from SI_SIGIO
Signed-off-by: "Eric W. Biederman"
08 Jul, 2017
1 commit
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Michael Ellerman reported that commit 8c6657cb50cb ("Switch flock
copyin/copyout primitives to copy_{from,to}_user()") broke his
networking on a bunch of PPC machines (64-bit kernel, 32-bit userspace).The reason is a brown-paper bug by that commit, which had the arguments
to "copy_flock_fields()" in the wrong order, breaking the compat
handling for file locking. Apparently very few people run 32-bit user
space on x86 any more, so the PPC people got the honor of noticing this
"feature".Michael also sent a minimal diff that just changed the order of the
arguments in that macro.This is not that minimal diff.
This not only changes the order of the arguments in the macro, it also
changes them to be pointers (to be consistent with all the other uses of
those pointers), and makes the functions that do all of this also have
the proper "const" attribution on the source pointers in order to make
issues like that (using the source as a destination) be really obvious.Reported-by: Michael Ellerman
Acked-by: Al Viro
Signed-off-by: Linus Torvalds
06 Jul, 2017
1 commit
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Pull misc user access cleanups from Al Viro:
"The first pile is assorted getting rid of cargo-culted access_ok(),
cargo-culted set_fs() and field-by-field copyouts.The same description applies to a lot of stuff in other branches -
this is just the stuff that didn't fit into a more specific topical
branch"* 'work.misc-set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
Switch flock copyin/copyout primitives to copy_{from,to}_user()
fs/fcntl: return -ESRCH in f_setown when pid/pgid can't be found
fs/fcntl: f_setown, avoid undefined behaviour
fs/fcntl: f_setown, allow returning error
lpfc debugfs: get rid of pointless access_ok()
adb: get rid of pointless access_ok()
isdn: get rid of pointless access_ok()
compat statfs: switch to copy_to_user()
fs/locks: don't mess with the address limit in compat_fcntl64
nfsd_readlink(): switch to vfs_get_link()
drbd: ->sendpage() never needed set_fs()
fs/locks: pass kernel struct flock to fcntl_getlk/setlk
fs: locks: Fix some troubles at kernel-doc comments
28 Jun, 2017
2 commits
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Some architectures (at least PPC) doesn't like get/put_user with
64-bit types on a 32-bit system. Use the variably sized copy
to/from user variants instead.Reported-by: Stephen Rothwell
Fixes: c75b1d9421f8 ("fs: add fcntl() interface for setting/getting write life time hints")
Signed-off-by: Jens Axboe -
Define a set of write life time hints:
RWH_WRITE_LIFE_NOT_SET No hint information set
RWH_WRITE_LIFE_NONE No hints about write life time
RWH_WRITE_LIFE_SHORT Data written has a short life time
RWH_WRITE_LIFE_MEDIUM Data written has a medium life time
RWH_WRITE_LIFE_LONG Data written has a long life time
RWH_WRITE_LIFE_EXTREME Data written has an extremely long life timeThe intent is for these values to be relative to each other, no
absolute meaning should be attached to these flag names.Add an fcntl interface for querying these flags, and also for
setting them as well:F_GET_RW_HINT Returns the read/write hint set on the
underlying inode.F_SET_RW_HINT Set one of the above write hints on the
underlying inode.F_GET_FILE_RW_HINT Returns the read/write hint set on the
file descriptor.F_SET_FILE_RW_HINT Set one of the above write hints on the
file descriptor.The user passes in a 64-bit pointer to get/set these values, and
the interface returns 0/-1 on success/error.Sample program testing/implementing basic setting/getting of write
hints is below.Add support for storing the write life time hint in the inode flags
and in struct file as well, and pass them to the kiocb flags. If
both a file and its corresponding inode has a write hint, then we
use the one in the file, if available. The file hint can be used
for sync/direct IO, for buffered writeback only the inode hint
is available.This is in preparation for utilizing these hints in the block layer,
to guide on-media data placement./*
* writehint.c: get or set an inode write hint
*/
#include
#include
#include
#include
#include
#include#ifndef F_GET_RW_HINT
#define F_LINUX_SPECIFIC_BASE 1024
#define F_GET_RW_HINT (F_LINUX_SPECIFIC_BASE + 11)
#define F_SET_RW_HINT (F_LINUX_SPECIFIC_BASE + 12)
#endifstatic char *str[] = { "RWF_WRITE_LIFE_NOT_SET", "RWH_WRITE_LIFE_NONE",
"RWH_WRITE_LIFE_SHORT", "RWH_WRITE_LIFE_MEDIUM",
"RWH_WRITE_LIFE_LONG", "RWH_WRITE_LIFE_EXTREME" };int main(int argc, char *argv[])
{
uint64_t hint;
int fd, ret;if (argc < 2) {
fprintf(stderr, "%s: file \n", argv[0]);
return 1;
}fd = open(argv[1], O_RDONLY);
if (fd < 0) {
perror("open");
return 2;
}if (argc > 2) {
hint = atoi(argv[2]);
ret = fcntl(fd, F_SET_RW_HINT, &hint);
if (ret < 0) {
perror("fcntl: F_SET_RW_HINT");
return 4;
}
}ret = fcntl(fd, F_GET_RW_HINT, &hint);
if (ret < 0) {
perror("fcntl: F_GET_RW_HINT");
return 3;
}printf("%s: hint %s\n", argv[1], str[hint]);
close(fd);
return 0;
}Reviewed-by: Martin K. Petersen
Signed-off-by: Jens Axboe
27 Jun, 2017
1 commit
-
... and lose HAVE_ARCH_...; if copy_{to,from}_user() on an
architecture sucks badly enough to make it a problem, we have
a worse problem.Signed-off-by: Al Viro
14 Jun, 2017
3 commits
-
The current implementation of F_SETOWN doesn't properly vet the argument
passed in and only returns an error if INT_MIN is passed in. If the
argument doesn't specify a valid pid/pgid, then we just end up cleaning
out the file->f_owner structure.What we really want is to only clean that out only in the case where
userland passed in an argument of 0. For anything else, we want to
return ESRCH if it doesn't refer to a valid pid.The relevant POSIX spec page is here:
http://pubs.opengroup.org/onlinepubs/9699919799/functions/fcntl.html
Cc: Jiri Slaby
Cc: zhong jiang
Signed-off-by: Jeff Layton -
fcntl(0, F_SETOWN, 0x80000000) triggers:
UBSAN: Undefined behaviour in fs/fcntl.c:118:7
negation of -2147483648 cannot be represented in type 'int':
CPU: 1 PID: 18261 Comm: syz-executor Not tainted 4.8.1-0-syzkaller #1
...
Call Trace:
...
[] ? f_setown+0x1d8/0x200
[] ? SyS_fcntl+0x999/0xf30
[] ? entry_SYSCALL_64_fastpath+0x23/0xc1Fix that by checking the arg parameter properly (against INT_MAX) before
"who = -who". And return immediatelly with -EINVAL in case it is wrong.
Note that according to POSIX we can return EINVAL:
http://pubs.opengroup.org/onlinepubs/9699919799/functions/fcntl.html[EINVAL]
The cmd argument is F_SETOWN and the value of the argument
is not valid as a process or process group identifier.[v2] returns an error, v1 used to fail silently
[v3] implement proper check for the bad value INT_MINSigned-off-by: Jiri Slaby
Cc: Jeff Layton
Cc: "J. Bruce Fields"
Cc: Alexander Viro
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Jeff Layton -
Allow f_setown to return an error value. We will fail in the next patch
with EINVAL for bad input to f_setown, so tile the path for the later
patch.Signed-off-by: Jiri Slaby
Reviewed-by: Jeff Layton
Cc: Jeff Layton
Cc: "J. Bruce Fields"
Cc: Alexander Viro
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Jeff Layton
01 Jun, 2017
1 commit
-
Instead write a proper compat syscall that calls common helpers.
[ jlayton: fix pointer dereferencing in fixup_compat_flock ]
Signed-off-by: Christoph Hellwig
Reviewed-by: Jeff Layton
Signed-off-by: Jeff Layton
27 May, 2017
1 commit
-
This will make it easier to implement a sane compat fcntl syscall.
[ jlayton: fix undeclared identifiers in 32-bit fcntl64 syscall handler ]
Signed-off-by: Christoph Hellwig
Reviewed-by: Jeff Layton
Signed-off-by: Jeff Layton
10 May, 2017
1 commit
-
Pull misc vfs updates from Al Viro:
"Assorted bits and pieces from various people. No common topic in this
pile, sorry"* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fs/affs: add rename exchange
fs/affs: add rename2 to prepare multiple methods
Make stat/lstat/fstatat pass AT_NO_AUTOMOUNT to vfs_statx()
fs: don't set *REFERENCED on single use objects
fs: compat: Remove warning from COMPATIBLE_IOCTL
remove pointless extern of atime_need_update_rcu()
fs: completely ignore unknown open flags
fs: add a VALID_OPEN_FLAGS
fs: remove _submit_bh()
fs: constify tree_descr arrays passed to simple_fill_super()
fs: drop duplicate header percpu-rwsem.h
fs/affs: bugfix: Write files greater than page size on OFS
fs/affs: bugfix: enable writes on OFS disks
fs/affs: remove node generation check
fs/affs: import amigaffs.h
fs/affs: bugfix: make symbolic links work again
27 Apr, 2017
1 commit
-
Add a central define for all valid open flags, and use it in the uniqueness
check.Signed-off-by: Christoph Hellwig
Signed-off-by: Al Viro
18 Apr, 2017
1 commit
-
Signed-off-by: Al Viro
02 Mar, 2017
1 commit
-
We are going to split out of , which
will have to be picked up from other headers and a couple of .c files.Create a trivial placeholder file that just
maps to to make this patch obviously correct and
bisectable.Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds
Cc: Mike Galbraith
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar
25 Dec, 2016
1 commit
-
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*'
sed -i -e "s!$PATT!#include !" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)to do the replacement at the end of the merge window.
Requested-by: Al Viro
Signed-off-by: Linus Torvalds
05 Dec, 2016
1 commit
-
Signed-off-by: Al Viro