The variable 'consumed' is initialized with the consumed count but immediately after that the consumed count is updated and assigned to 'consumed' again thus overwriting the previous value. So, drop the unneeded initialization. Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Link: https://lkml.kernel.org/r/20201005205727.1147-1-sudipm.mukherjee@gmail.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kmemleak report memory leak as follows:
unreferenced object 0x607ee4e5f948 (size 8):
comm "syz-executor.1", pid 2098, jiffies 4295031601 (age 288.468s)
hex dump (first 8 bytes):
00 00 00 00 00 00 00 00 ........
backtrace:
relay_open kernel/relay.c:583 [inline]
relay_open+0xb6/0x970 kernel/relay.c:563
do_blk_trace_setup+0x4a8/0xb20 kernel/trace/blktrace.c:557
__blk_trace_setup+0xb6/0x150 kernel/trace/blktrace.c:597
blk_trace_ioctl+0x146/0x280 kernel/trace/blktrace.c:738
blkdev_ioctl+0xb2/0x6a0 block/ioctl.c:613
block_ioctl+0xe5/0x120 fs/block_dev.c:1871
vfs_ioctl fs/ioctl.c:48 [inline]
__do_sys_ioctl fs/ioctl.c:753 [inline]
__se_sys_ioctl fs/ioctl.c:739 [inline]
__x64_sys_ioctl+0x170/0x1ce fs/ioctl.c:739
do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
'chan->buf' is malloced in relay_open() by alloc_percpu() but not free
while destroy the relay channel. Fix it by adding free_percpu() before
return from relay_destroy_channel().
Fixes: 017c59c042d0 ("relay: Use per CPU constructs for the relay channel buffer pointers")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: David Rientjes <rientjes@google.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Akash Goel <akash.goel@intel.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200817122826.48518-1-weiyongjun1@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert comments that reference mmap_sem to reference mmap_lock instead. [akpm@linux-foundation.org: fix up linux-next leftovers] [akpm@linux-foundation.org: s/lockaphore/lock/, per Vlastimil] [akpm@linux-foundation.org: more linux-next fixups, per Michel] Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Laurent Dufour <ldufour@linux.ibm.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-13-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When reading, read_pos should start with bytes_consumed, not file->f_pos. Because when there is more than one reader, the read_pos corresponding to file->f_pos may have been consumed, which will cause the data that has been consumed to be read and the bytes_consumed update error. Signed-off-by: Pengcheng Yang <yangpc@wangsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jann Horn <jannh@google.com> Cc: Al Viro <viro@zeniv.linux.org.uk>e Link: http://lkml.kernel.org/r/1579691175-28949-1-git-send-email-yangpc@wangsu.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
alloc_percpu() may return NULL, which means chan->buf may be set to NULL.
In that case, when we do *per_cpu_ptr(chan->buf, ...), we dereference an
invalid pointer:
BUG: Unable to handle kernel data access at 0x7dae0000
Faulting instruction address: 0xc0000000003f3fec
...
NIP relay_open+0x29c/0x600
LR relay_open+0x270/0x600
Call Trace:
relay_open+0x264/0x600 (unreliable)
__blk_trace_setup+0x254/0x600
blk_trace_setup+0x68/0xa0
sg_ioctl+0x7bc/0x2e80
do_vfs_ioctl+0x13c/0x1300
ksys_ioctl+0x94/0x130
sys_ioctl+0x48/0xb0
system_call+0x5c/0x68
Check if alloc_percpu returns NULL.
This was found by syzkaller both on x86 and powerpc, and the reproducer
it found on powerpc is capable of hitting the issue as an unprivileged
user.
Fixes: 017c59c042d0 ("relay: Use per CPU constructs for the relay channel buffer pointers")
Reported-by: syzbot+1e925b4b836afe85a1c6@syzkaller-ppc64.appspotmail.com
Reported-by: syzbot+587b2421926808309d21@syzkaller-ppc64.appspotmail.com
Reported-by: syzbot+58320b7171734bf79d26@syzkaller.appspotmail.com
Reported-by: syzbot+d6074fb08bdb2e010520@syzkaller.appspotmail.com
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Akash Goel <akash.goel@intel.com>
Cc: Andrew Donnellan <ajd@linux.ibm.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Salvatore Bonaccorso <carnil@debian.org>
Cc: <stable@vger.kernel.org> [4.10+]
Link: http://lkml.kernel.org/r/20191219121256.26480-1-dja@axtens.net
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull splice updates from Al Viro: "Christoph's assorted splice cleanups" * 'work.splice' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: rename pipe_buf ->steal to ->try_steal fs: make the pipe_buf_operations ->confirm operation optional fs: make the pipe_buf_operations ->steal operation optional trace: remove tracing_pipe_buf_ops pipe: merge anon_pipe_buf*_ops fs: simplify do_splice_from fs: simplify do_splice_to
And replace the arcane return value convention with a simple bool where true means success and false means failure. [AV: braino fix folded in] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Just return 0 for success if it is not present. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Some filesystem references got broken by a previous patch series I submitted. Address those. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Acked-by: David Sterba <dsterba@suse.com> # fs/affs/Kconfig Link: https://lore.kernel.org/r/57318c53008dbda7f6f4a5a9e5787f4d37e8565a.1586881715.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Pull misc vfs updates from Al Viro: "Assorted fixes (really no common topic here)" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: vfs: Make __vfs_write() static vfs: fix preadv64v2 and pwritev64v2 compat syscalls with offset == -1 pipe: stop using ->can_merge splice: don't merge into linked buffers fs: move generic stat response attr handling to vfs_getattr_nosec orangefs: don't reinitialize result_mask in ->getattr fs/devpts: always delete dcache dentry-s in dput()