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Pull structleak fix from Kees Cook:
"Disable gcc-based stack variable auto-init under KASAN (Arnd
Bergmann).
This fixes a bunch of build warnings under KASAN and the
gcc-plugin-based stack auto-initialization features (which are
arguably redundant, so better to let KASAN control this)"
* tag 'meminit-v5.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
structleak: disable STRUCTLEAK_BYREF in combination with KASAN_STACK
Pull Kbuild fixes from Masahiro Yamada:
- add compile_commands.json to .gitignore
- fix false-positive warning from gen_compile_commands.py after
allnoconfig build
- remove unused code
* tag 'kbuild-fixes-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: remove unused single-used-m
gen_compile_commands: lower the entry count threshold
.gitignore: Add compilation database file
kbuild: remove unused objectify macro
The combination of KASAN_STACK and GCC_PLUGIN_STRUCTLEAK_BYREF
leads to much larger kernel stack usage, as seen from the warnings
about functions that now exceed the 2048 byte limit:
drivers/media/i2c/tvp5150.c:253:1: error: the frame size of 3936 bytes is larger than 2048 bytes
drivers/media/tuners/r820t.c:1327:1: error: the frame size of 2816 bytes is larger than 2048 bytes
drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_n.c:16552:1: error: the frame size of 3144 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]
fs/ocfs2/aops.c:1892:1: error: the frame size of 2088 bytes is larger than 2048 bytes
fs/ocfs2/dlm/dlmrecovery.c:737:1: error: the frame size of 2088 bytes is larger than 2048 bytes
fs/ocfs2/namei.c:1677:1: error: the frame size of 2584 bytes is larger than 2048 bytes
fs/ocfs2/super.c:1186:1: error: the frame size of 2640 bytes is larger than 2048 bytes
fs/ocfs2/xattr.c:3678:1: error: the frame size of 2176 bytes is larger than 2048 bytes
net/bluetooth/l2cap_core.c:7056:1: error: the frame size of 2144 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]
net/bluetooth/l2cap_core.c: In function 'l2cap_recv_frame':
net/bridge/br_netlink.c:1505:1: error: the frame size of 2448 bytes is larger than 2048 bytes
net/ieee802154/nl802154.c:548:1: error: the frame size of 2232 bytes is larger than 2048 bytes
net/wireless/nl80211.c:1726:1: error: the frame size of 2224 bytes is larger than 2048 bytes
net/wireless/nl80211.c:2357:1: error: the frame size of 4584 bytes is larger than 2048 bytes
net/wireless/nl80211.c:5108:1: error: the frame size of 2760 bytes is larger than 2048 bytes
net/wireless/nl80211.c:6472:1: error: the frame size of 2112 bytes is larger than 2048 bytes
The structleak plugin was previously disabled for CONFIG_COMPILE_TEST,
but meant we missed some bugs, so this time we should address them.
The frame size warnings are distracting, and risking a kernel stack
overflow is generally not beneficial to performance, so it may be best
to disallow that particular combination. This can be done by turning
off either one. I picked the dependency in GCC_PLUGIN_STRUCTLEAK_BYREF
and GCC_PLUGIN_STRUCTLEAK_BYREF_ALL, as this option is designed to
make uninitialized stack usage less harmful when enabled on its own,
but it also prevents KASAN from detecting those cases in which it was
in fact needed.
KASAN_STACK is currently implied by KASAN on gcc, but could be made a
user selectable option if we want to allow combining (non-stack) KASAN
with GCC_PLUGIN_STRUCTLEAK_BYREF.
Note that it would be possible to specifically address the files that
print the warning, but presumably the overall stack usage is still
significantly higher than in other configurations, so this would not
address the full problem.
I could not test this with CONFIG_INIT_STACK_ALL, which may or may not
suffer from a similar problem.
Fixes: 81a56f6dcd20 ("gcc-plugins: structleak: Generalize to all variable types")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20190722114134.3123901-1-arnd@arndb.de
Signed-off-by: Kees Cook <keescook@chromium.org>
Pull char/misc driver fixes from Greg KH:
"Here are some small char and misc driver fixes for 5.3-rc2 to resolve
some reported issues.
Nothing major at all, some binder bugfixes for issues found, some new
mei device ids, firmware building warning fixes, habanalabs fixes, a
few other build fixes, and a MAINTAINERS update.
All of these have been in linux-next with no reported issues"
* tag 'char-misc-5.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
test_firmware: fix a memory leak bug
hpet: Fix division by zero in hpet_time_div()
eeprom: make older eeprom drivers select NVMEM_SYSFS
vmw_balloon: Remove Julien from the maintainers list
fpga-manager: altera-ps-spi: Fix build error
mei: me: add mule creek canyon (EHL) device ids
binder: prevent transactions to context manager from its own process.
binder: Set end of SG buffer area properly.
firmware: Fix missing inline
firmware: fix build errors in paged buffer handling code
habanalabs: don't reset device when getting VRHOT
habanalabs: use %pad for printing a dma_addr_t
This is unused since commit 9f69a496f100 ("kbuild: split out *.mod out
of {single,multi}-used-m rules").
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Pull tty fixes from Greg KH:
"Here are two tty/vt fixes:
- delete the netx-serial driver as the arch has been removed, no need
to keep the serial driver for it around either.
- vt console_lock fix to resolve a reported noisy warning at runtime
Both of these have been in linux-next with no reported issues"
* tag 'tty-5.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
vt: Grab console_lock around con_is_bound in show_bind
tty: serial: netx: Delete driver
In test_firmware_init(), the buffer pointed to by the global pointer
'test_fw_config' is allocated through kzalloc(). Then, the buffer is
initialized in __test_firmware_config_init(). In the case that the
initialization fails, the following execution in test_firmware_init() needs
to be terminated with an error code returned to indicate this failure.
However, the allocated buffer is not freed on this execution path, leading
to a memory leak bug.
To fix the above issue, free the allocated buffer before returning from
test_firmware_init().
Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Link: https://lore.kernel.org/r/1563084696-6865-1-git-send-email-wang6495@umn.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Running gen_compile_commands.py after building the kernel with
allnoconfig gave this:
$ ./scripts/gen_compile_commands.py
WARNING: Found 449 entries. Have you compiled the kernel?
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Pull tracing warning fix from Steven Rostedt:
"Make the GCC 9 warning for sub struct memset go away.
GCC 9 now warns about calling memset() on partial structures when it
goes across multiple fields. This adds a helper for the place in
tracing that does this type of clearing of a structure"
* tag 'trace-v5.2-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Silence GCC 9 array bounds warning
Pull SPDX fixes from Greg KH:
"Here are some small SPDX fixes for 5.3-rc2 for things that came in
during the 5.3-rc1 merge window that we previously missed.
Only three small patches here:
- two uapi patches to resolve some SPDX tags that were not correct
- fix an invalid SPDX tag in the iomap Makefile file
All have been properly reviewed on the public mailing lists"
* tag 'spdx-5.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx:
iomap: fix Invalid License ID
treewide: remove SPDX "WITH Linux-syscall-note" from kernel-space headers again
treewide: add "WITH Linux-syscall-note" to SPDX tag of uapi headers
Not really harmful not to, but also not harm in grabbing the lock. And
this shuts up a new WARNING I introduced in commit ddde3c18b700 ("vt:
More locking checks").
Reported-by: Jens Remus <jremus@linux.ibm.com>
Cc: linux-kernel@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-fbdev@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Martin Hostettler <textshell@uchuujin.de>
Cc: Adam Borowski <kilobyte@angband.pl>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Sam Ravnborg <sam@ravnborg.org>
Fixes: ddde3c18b700 ("vt: More locking checks")
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Tested-by: Jens Remus <jremus@linux.ibm.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://lore.kernel.org/r/20190718080903.22622-1-daniel.vetter@ffwll.ch
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The base value in do_div() called by hpet_time_div() is truncated from
unsigned long to uint32_t, resulting in a divide-by-zero exception.
UBSAN: Undefined behaviour in ../drivers/char/hpet.c:572:2
division by zero
CPU: 1 PID: 23682 Comm: syz-executor.3 Not tainted 4.4.184.x86_64+ #4
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
0000000000000000 b573382df1853d00 ffff8800a3287b98 ffffffff81ad7561
ffff8800a3287c00 ffffffff838b35b0 ffffffff838b3860 ffff8800a3287c20
0000000000000000 ffff8800a3287bb0 ffffffff81b8f25e ffffffff838b35a0
Call Trace:
[<ffffffff81ad7561>] __dump_stack lib/dump_stack.c:15 [inline]
[<ffffffff81ad7561>] dump_stack+0xc1/0x120 lib/dump_stack.c:51
[<ffffffff81b8f25e>] ubsan_epilogue+0x12/0x8d lib/ubsan.c:166
[<ffffffff81b900cb>] __ubsan_handle_divrem_overflow+0x282/0x2c8 lib/ubsan.c:262
[<ffffffff823560dd>] hpet_time_div drivers/char/hpet.c:572 [inline]
[<ffffffff823560dd>] hpet_ioctl_common drivers/char/hpet.c:663 [inline]
[<ffffffff823560dd>] hpet_ioctl_common.cold+0xa8/0xad drivers/char/hpet.c:577
[<ffffffff81e63d56>] hpet_ioctl+0xc6/0x180 drivers/char/hpet.c:676
[<ffffffff81711590>] vfs_ioctl fs/ioctl.c:43 [inline]
[<ffffffff81711590>] file_ioctl fs/ioctl.c:470 [inline]
[<ffffffff81711590>] do_vfs_ioctl+0x6e0/0xf70 fs/ioctl.c:605
[<ffffffff81711eb4>] SYSC_ioctl fs/ioctl.c:622 [inline]
[<ffffffff81711eb4>] SyS_ioctl+0x94/0xc0 fs/ioctl.c:613
[<ffffffff82846003>] tracesys_phase2+0x90/0x95
The main C reproducer autogenerated by syzkaller,
syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
memcpy((void*)0x20000100, "/dev/hpet\000", 10);
syscall(__NR_openat, 0xffffffffffffff9c, 0x20000100, 0, 0);
syscall(__NR_ioctl, r[0], 0x40086806, 0x40000000000000);
Fix it by using div64_ul().
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Zhang HongJun <zhanghongjun2@huawei.com>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20190711132757.130092-1-wangkefeng.wang@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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