linux-toradex.git/kernel/relay.c, branch v6.2-rc3

relay: fix type mismatch when allocating memory in relay_create_buf()

2022-12-12T03:30:19+00:00

The 'padding' field of the 'rchan_buf' structure is an array of 'size_t'
elements, but the memory is allocated for an array of 'size_t *' elements.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Link: https://lkml.kernel.org/r/20221129092002.3538384-1-Ilia.Gavrilov@infotecs.ru
Fixes: b86ff981a825 ("[PATCH] relay: migrate from relayfs to a generic relay API")
Signed-off-by: Ilia.Gavrilov 
Cc: Colin Ian King 
Cc: Jens Axboe 
Cc: wuchi 
Signed-off-by: Andrew Morton

relay: use strscpy() is more robust and safer

2022-12-12T03:30:18+00:00

The implementation of strscpy() is more robust and safer.  That's now the
recommended way to copy NUL terminated strings.

Link: https://lkml.kernel.org/r/202211220853259244666@zte.com.cn
Signed-off-by: Xu Panda 
Signed-off-by: Yang Yang 
Cc: Colin Ian King 
Cc: Jens Axboe 
Cc: wuchi 
Signed-off-by: Andrew Morton

relay: use kvcalloc to alloc page array in relay_alloc_page_array

2022-10-03T21:21:43+00:00

kvcalloc() is safer because it will check the integer overflows, and using
it will simple the logic of allocation size.

Link: https://lkml.kernel.org/r/20220909101025.82955-1-wuchi.zero@gmail.com
Signed-off-by: wuchi 
Cc: Christoph Hellwig 
Cc: Jens Axboe 
Signed-off-by: Andrew Morton

relay: remove redundant assignment to pointer buf

2022-05-13T03:38:37+00:00

Pointer buf is being assigned a value that is not being read, buf is being
re-assigned in the next starement.  The assignment is redundant and can be
removed.

Cleans up clang scan build warning:
kernel/relay.c:443:8: warning: Although the value stored to 'buf' is
used in the enclosing expression, the value is never actually read
from 'buf' [deadcode.DeadStores]

Link: https://lkml.kernel.org/r/20220508212152.58753-1-colin.i.king@gmail.com
Signed-off-by: Colin Ian King 
Reviewed-by: Jens Axboe 
Cc: Christoph Hellwig 
Cc: Kalle Valo 
Signed-off-by: Andrew Morton

relay: allow the use of const callback structs

2020-12-16T06:46:18+00:00

None of the relay users require the use of mutable structs for callbacks,
however the relay code does.  Instead of assigning the default callback
for subbuf_start, add a wrapper to conditionally call the client callback
if available, and fall back to default behaviour otherwise.

This lets all relay users make their struct rchan_callbacks const data.

[jani.nikula@intel.com: cleanups, per Christoph]
  Link: https://lkml.kernel.org/r/20201124115412.32402-1-jani.nikula@intel.com

Link: https://lkml.kernel.org/r/cc3ff292e4eb4fdc56bee3d690c7b8e39209cd37.1606153547.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula 
Reviewed-by: Christoph Hellwig 
Cc: Jens Axboe 
Cc: Kalle Valo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

relay: make create_buf_file and remove_buf_file callbacks mandatory

2020-12-16T06:46:18+00:00

All clients provide create_buf_file and remove_buf_file callbacks, and
they're required for relay to make sense.  There is no point in them being
optional.

Also document whether each callback is mandatory/optional.

Link: https://lkml.kernel.org/r/88003c1527386b93036e286e7917f1e33aec84ac.1606153547.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula 
Suggested-by: Christoph Hellwig 
Reviewed-by: Christoph Hellwig 
Cc: Jens Axboe 
Cc: Kalle Valo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

relay: require non-NULL callbacks in relay_open()

2020-12-16T06:46:18+00:00

There are no clients passing NULL callbacks, which makes sense as it
wouldn't even create a file.  Require non-NULL callbacks, and throw away
the handling for NULL callbacks.

Link: https://lkml.kernel.org/r/e40642f3b027d2bb6bc851ddb60e0a61ea51f5f8.1606153547.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula 
Suggested-by: Christoph Hellwig 
Reviewed-by: Christoph Hellwig 
Cc: Jens Axboe 
Cc: Kalle Valo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

relay: remove unused buf_mapped and buf_unmapped callbacks

2020-12-16T06:46:18+00:00

Patch series "relay: cleanup and const callbacks", v2.

None of the relay users require the use of mutable structs for callbacks,
however the relay code does.  Instead of assigning default callbacks when
there is none, add callback wrappers to conditionally call the client
callbacks if available, and fall back to default behaviour (typically
no-op) otherwise.

This lets all relay users make their struct rchan_callbacks const data.

This series starts with a number of cleanups first based on Christoph's
feedback.

This patch (of 9):

No relay client uses the buf_mapped or buf_unmapped callbacks.  Remove
them.  This makes relay's vm_operations_struct close callback a dummy,
remove it as well.

Link: https://lkml.kernel.org/r/cover.1606153547.git.jani.nikula@intel.com
Link: https://lkml.kernel.org/r/c69fff6e0cd485563604240bbfcc028434983bec.1606153547.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula 
Suggested-by: Christoph Hellwig 
Reviewed-by: Christoph Hellwig 
Cc: Jens Axboe 
Cc: Kalle Valo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kernel/relay.c: drop unneeded initialization

2020-10-16T18:11:22+00:00

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 
Signed-off-by: Andrew Morton 
Reviewed-by: Andrew Morton 
Link: https://lkml.kernel.org/r/20201005205727.1147-1-sudipm.mukherjee@gmail.com
Signed-off-by: Linus Torvalds

kernel/relay.c: fix memleak on destroy relay channel

2020-08-21T16:52:53+00:00

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 
Signed-off-by: Wei Yongjun 
Signed-off-by: Andrew Morton 
Reviewed-by: Chris Wilson 
Cc: Al Viro 
Cc: Michael Ellerman 
Cc: David Rientjes 
Cc: Michel Lespinasse 
Cc: Daniel Axtens 
Cc: Thomas Gleixner 
Cc: Akash Goel 
Cc: 
Link: http://lkml.kernel.org/r/20200817122826.48518-1-weiyongjun1@huawei.com
Signed-off-by: Linus Torvalds