[ Upstream commit 2307d0bc9d ]
Fixes the following W=1 kernel build warning(s):
In file included from drivers/net/wireless/wl3501_cs.c:57:
drivers/net/wireless/wl3501_cs.c:143: warning: Function parameter or member 'reg_domain' not described in 'iw_valid_channel'
drivers/net/wireless/wl3501_cs.c:143: warning: Function parameter or member 'channel' not described in 'iw_valid_channel'
drivers/net/wireless/wl3501_cs.c:162: warning: Function parameter or member 'reg_domain' not described in 'iw_default_channel'
drivers/net/wireless/wl3501_cs.c:248: warning: Function parameter or member 'this' not described in 'wl3501_set_to_wla'
drivers/net/wireless/wl3501_cs.c:270: warning: Function parameter or member 'this' not described in 'wl3501_get_from_wla'
drivers/net/wireless/wl3501_cs.c:467: warning: Function parameter or member 'this' not described in 'wl3501_send_pkt'
drivers/net/wireless/wl3501_cs.c:467: warning: Function parameter or member 'data' not described in 'wl3501_send_pkt'
drivers/net/wireless/wl3501_cs.c:467: warning: Function parameter or member 'len' not described in 'wl3501_send_pkt'
drivers/net/wireless/wl3501_cs.c:729: warning: Function parameter or member 'this' not described in 'wl3501_block_interrupt'
drivers/net/wireless/wl3501_cs.c:746: warning: Function parameter or member 'this' not described in 'wl3501_unblock_interrupt'
drivers/net/wireless/wl3501_cs.c:1124: warning: Function parameter or member 'irq' not described in 'wl3501_interrupt'
drivers/net/wireless/wl3501_cs.c:1124: warning: Function parameter or member 'dev_id' not described in 'wl3501_interrupt'
drivers/net/wireless/wl3501_cs.c:1257: warning: Function parameter or member 'dev' not described in 'wl3501_reset'
drivers/net/wireless/wl3501_cs.c:1420: warning: Function parameter or member 'link' not described in 'wl3501_detach'
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Fox Chen <mhchen@golf.ccl.itri.org.tw>
Cc: de Melo <acme@conectiva.com.br>
Cc: Gustavo Niemeyer <niemeyer@conectiva.com>
Cc: linux-wireless@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200826093401.1458456-21-lee.jones@linaro.org
Stable-dep-of: 391af06a02 ("wifi: wl3501_cs: Fix an error handling path in wl3501_probe()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 08880713ce ]
If CONFIG_DEBUG_FS is not set:
regulator: Failed to create debugfs directory
...
regulator-dummy: Failed to create debugfs directory
As per the comments for debugfs_create_dir(), errors returned by this
function should be expected, and ignored:
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
* returned.
*
* NOTE: it's expected that most callers should _ignore_ the errors returned
* by this function. Other debugfs functions handle the fact that the "dentry"
* passed to them could be an error and they don't crash in that case.
* Drivers should generally work fine even if debugfs fails to init anyway.
Adhere to the debugfs spirit, and streamline all operations by:
1. Demoting the importance of the printed error messages to debug
level, like is already done in create_regulator(),
2. Further ignoring any returned errors, as by design, all debugfs
functions are no-ops when passed an error pointer.
Fixes: 2bf1c45be3 ("regulator: Fix error checking for debugfs_create_dir")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/2f8bb6e113359ddfab7b59e4d4274bd4c06d6d0a.1685013051.git.geert+renesas@glider.be
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0d9b41daa5 ]
If sock->service_name is NULL, the local variable
service_name_tlv_length will not be assigned by nfc_llcp_build_tlv(),
later leading to using value frmo the stack. Smatch warning:
net/nfc/llcp_commands.c:442 nfc_llcp_send_connect() error: uninitialized symbol 'service_name_tlv_length'.
Fixes: de9e5aeb4f ("NFC: llcp: Fix usage of llcp_add_tlv()")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3df40eb3a2 ]
Several functions receive pointers to u8, char or sk_buff but do not
modify the contents so make them const. This allows doing the same for
local variables and in total makes the code a little bit safer.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 0d9b41daa5 ("nfc: llcp: fix possible use of uninitialized variable in nfc_llcp_send_connect()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f24292e827 ]
For the reasons also described in commit b383e8abed ("wifi: ath9k: avoid
uninit memory read in ath9k_htc_rx_msg()"), ath9k_htc_rx_msg() should
validate pkt_len before accessing the SKB.
For example, the obtained SKB may have been badly constructed with
pkt_len = 8. In this case, the SKB can only contain a valid htc_frame_hdr
but after being processed in ath9k_htc_rx_msg() and passed to
ath9k_wmi_ctrl_rx() endpoint RX handler, it is expected to have a WMI
command header which should be located inside its data payload.
Implement sanity checking inside ath9k_wmi_ctrl_rx(). Otherwise, uninit
memory can be referenced.
Tested on Qualcomm Atheros Communications AR9271 802.11n .
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Fixes: fb9987d0f7 ("ath9k_htc: Support for AR9271 chipset.")
Reported-and-tested-by: syzbot+f2cb6e0ffdb961921e4d@syzkaller.appspotmail.com
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20230424183348.111355-1-pchelkin@ispras.ru
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1b9c3ddcec ]
checker_stack_use_t32strd() and kprobe_handler() can be made static since
they are not used from other files, while coverage_start_registers()
and __kprobes_test_case() are used from assembler code, and just need
a declaration to avoid a warning with the global definition.
arch/arm/probes/kprobes/checkers-common.c:43:18: error: no previous prototype for 'checker_stack_use_t32strd'
arch/arm/probes/kprobes/core.c:236:16: error: no previous prototype for 'kprobe_handler'
arch/arm/probes/kprobes/test-core.c:723:10: error: no previous prototype for 'coverage_start_registers'
arch/arm/probes/kprobes/test-core.c:918:14: error: no previous prototype for '__kprobes_test_case_start'
arch/arm/probes/kprobes/test-core.c:952:14: error: no previous prototype for '__kprobes_test_case_end_16'
arch/arm/probes/kprobes/test-core.c:967:14: error: no previous prototype for '__kprobes_test_case_end_32'
Fixes: 6624cf651f ("ARM: kprobes: collects stack consumption for store instructions")
Fixes: 454f3e132d ("ARM/kprobes: Remove jprobe arm implementation")
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 4658fe81b3 ]
After commit 3382388d71 ("intel_rapl: abstract RAPL common code"),
accessing to IOSF_MBI interface is done in the RAPL common code.
Thus it is the CONFIG_INTEL_RAPL_CORE that has dependency of
CONFIG_IOSF_MBI, while CONFIG_INTEL_RAPL_MSR does not.
This problem was not exposed previously because all the previous RAPL
common code users, aka, the RAPL MSR and MMIO I/F drivers, have
CONFIG_IOSF_MBI selected.
Fix the CONFIG_IOSF_MBI dependency in RAPL code. This also fixes a build
time failure when the RAPL TPMI I/F driver is introduced without
selecting CONFIG_IOSF_MBI.
x86_64-linux-ld: vmlinux.o: in function `set_floor_freq_atom':
intel_rapl_common.c:(.text+0x2dac9b8): undefined reference to `iosf_mbi_write'
x86_64-linux-ld: intel_rapl_common.c:(.text+0x2daca66): undefined reference to `iosf_mbi_read'
Reference to iosf_mbi.h is also removed from the RAPL MSR I/F driver.
Fixes: 3382388d71 ("intel_rapl: abstract RAPL common code")
Reported-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/all/20230601213246.3271412-1-arnd@kernel.org
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e5d1c87220 ]
Currently, while calculating residency and latency values, right
operands may overflow if resulting values are big enough.
To prevent this, albeit unlikely case, play it safe and convert
right operands to left ones' type s64.
Found by Linux Verification Center (linuxtesting.org) with static
analysis tool SVACE.
Fixes: 30f604283e ("PM / Domains: Allow domain power states to be read from DT")
Signed-off-by: Nikita Zhandarovich <n.zhandarovich@fintech.ru>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8b5bf64c89 ]
Smatch reports:
drivers/clocksource/timer-cadence-ttc.c:529 ttc_timer_probe()
warn: 'timer_baseaddr' from of_iomap() not released on lines: 498,508,516.
timer_baseaddr may have the problem of not being released after use,
I replaced it with the devm_of_iomap() function and added the clk_put()
function to cleanup the "clk_ce" and "clk_cs".
Fixes: e932900a32 ("arm: zynq: Use standard timer binding")
Fixes: 70504f311d ("clocksource/drivers/cadence_ttc: Convert init function to return error")
Signed-off-by: Feng Mingxi <m202271825@hust.edu.cn>
Reviewed-by: Dongliang Mu <dzm91@hust.edu.cn>
Acked-by: Michal Simek <michal.simek@amd.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230425065611.702917-1-m202271825@hust.edu.cn
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2ae6aaf769 ]
When removing a disk with replacement, the replacement will be used to
replace rdev. During this process, there is a brief window in which both
rdev and replacement are read as NULL in raid10_write_request(). This
will result in io not being submitted but it should be.
//remove //write
raid10_remove_disk raid10_write_request
mirror->rdev = NULL
read rdev -> NULL
mirror->rdev = mirror->replacement
mirror->replacement = NULL
read replacement -> NULL
Fix it by reading replacement first and rdev later, meanwhile, use smp_mb()
to prevent memory reordering.
Fixes: 475b0321a4 ("md/raid10: writes should get directed to replacement as well as original.")
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230602091839.743798-3-linan666@huaweicloud.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 34817a2441 ]
There are two check of 'mreplace' in raid10_sync_request(). In the first
check, 'need_replace' will be set and 'mreplace' will be used later if
no-Faulty 'mreplace' exists, In the second check, 'mreplace' will be
set to NULL if it is Faulty, but 'need_replace' will not be changed
accordingly. null-ptr-deref occurs if Faulty is set between two check.
Fix it by merging two checks into one. And replace 'need_replace' with
'mreplace' because their values are always the same.
Fixes: ee37d7314a ("md/raid10: Fix raid10 replace hang when new added disk faulty")
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230527072218.2365857-2-linan666@huaweicloud.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 301867b1c1 ]
If we write a large number to md/bitmap_set_bits, md_bitmap_checkpage()
will return -EINVAL because 'page >= bitmap->pages', but the return value
was not checked immediately in md_bitmap_get_counter() in order to set
*blocks value and slab-out-of-bounds occurs.
Move check of 'page >= bitmap->pages' to md_bitmap_get_counter() and
return directly if true.
Fixes: ef42567335 ("md/bitmap: optimise scanning of empty bitmaps.")
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230515134808.3936750-2-linan666@huaweicloud.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e6b2fac36f ]
rdtgroup_tasks_assigned() and show_rdt_tasks() loop over threads testing
for a CTRL/MON group match by closid/rmid with the provided rdtgrp.
Further down the file are helpers to do this, move these further up and
make use of them here.
These helpers additionally check for alloc/mon capable. This is harmless
as rdtgroup_mkdir() tests these capable flags before allowing the config
directories to be created.
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Link: https://lkml.kernel.org/r/20200708163929.2783-7-james.morse@arm.com
Stable-dep-of: 2997d94b5d ("x86/resctrl: Only show tasks' pid in current pid namespace")
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit f99e6d7c4e upstream.
While bringing hardware up we should perform a full reset including the
switch bit (BGMAC_BCMA_IOCTL_SW_RESET aka SICF_SWRST). It's what
specification says and what reference driver does.
This seems to be critical for the BCM5358. Without this hardware doesn't
get initialized properly and doesn't seem to transmit or receive any
packets.
Originally bgmac was calling bgmac_chip_reset() before setting
"has_robosw" property which resulted in expected behaviour. That has
changed as a side effect of adding platform device support which
regressed BCM5358 support.
Fixes: f6a95a2495 ("net: ethernet: bgmac: Add platform device support")
Cc: Jon Mason <jdmason@kudzu.us>
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20230227091156.19509-1-zajec5@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e1b37563ca upstream.
gtags considers any file outside of its current working directory
"outside the source tree" and refuses to index it. For O= kernel builds,
or when "make" is invoked from a directory other then the kernel source
tree, gtags ignores the entire kernel source and generates an empty
index.
Force-set gtags current working directory to the kernel source tree.
Due to commit 9da0763bdd ("kbuild: Use relative path when building in
a subdir of the source tree"), if the kernel build is done in a
sub-directory of the kernel source tree, the kernel Makefile will set
the kernel's $srctree to ".." for shorter compile-time and run-time
warnings. Consequently, the list of files to be indexed will be in the
"../*" form, rendering all such paths invalid once gtags switches to the
kernel source tree as its current working directory.
If gtags indexing is requested and the build directory is not the kernel
source tree, index all files in absolute-path form.
Note, indexing in absolute-path form will not affect the generated
index, as paths in gtags indices are always relative to the gtags "root
directory" anyway (as evidenced by "gtags --dump").
Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c75f5a5506 upstream.
A use-after-free bug may occur if init_imstt invokes framebuffer_release
and free the info ptr. The caller, imsttfb_probe didn't notice that and
still keep the ptr as private data in pdev.
If we remove the driver which will call imsttfb_remove to make cleanup,
UAF happens.
Fix it by return error code if bad case happens in init_imstt.
Signed-off-by: Zheng Wang <zyytlz.wz@163.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f9c9987bf5 upstream.
Monitoring idletask::thread_info::flags in mwait_play_dead() has been an
obvious choice as all what is needed is a cache line which is not written
by other CPUs.
But there is a use case where a "dead" CPU needs to be brought out of
MWAIT: kexec().
This is required as kexec() can overwrite text, pagetables, stacks and the
monitored cacheline of the original kernel. The latter causes MWAIT to
resume execution which obviously causes havoc on the kexec kernel which
results usually in triple faults.
Use a dedicated per CPU storage to prepare for that.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230615193330.434553750@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 504a10d9e4 upstream.
On corrupt gfs2 file systems the evict code can try to reference the
journal descriptor structure, jdesc, after it has been freed and set to
NULL. The sequence of events is:
init_journal()
...
fail_jindex:
gfs2_jindex_free(sdp); <------frees journals, sets jdesc = NULL
if (gfs2_holder_initialized(&ji_gh))
gfs2_glock_dq_uninit(&ji_gh);
fail:
iput(sdp->sd_jindex); <--references jdesc in evict_linked_inode
evict()
gfs2_evict_inode()
evict_linked_inode()
ret = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
<------references the now freed/zeroed sd_jdesc pointer.
The call to gfs2_trans_begin is done because the truncate_inode_pages
call can cause gfs2 events that require a transaction, such as removing
journaled data (jdata) blocks from the journal.
This patch fixes the problem by adding a check for sdp->sd_jdesc to
function gfs2_evict_inode. In theory, this should only happen to corrupt
gfs2 file systems, when gfs2 detects the problem, reports it, then tries
to evict all the system inodes it has read in up to that point.
Reported-by: Yang Lan <lanyang0908@gmail.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
[DP: adjusted context]
Signed-off-by: Dragos-Marian Panait <dragos.panait@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Upstream commit: 522b1d6921
Add a fix for the Zen2 VZEROUPPER data corruption bug where under
certain circumstances executing VZEROUPPER can cause register
corruption or leak data.
The optimal fix is through microcode but in the case the proper
microcode revision has not been applied, enable a fallback fix using
a chicken bit.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 22ed903eee upstream.
syzbot detected a crash during log recovery:
XFS (loop0): Mounting V5 Filesystem bfdc47fc-10d8-4eed-a562-11a831b3f791
XFS (loop0): Torn write (CRC failure) detected at log block 0x180. Truncating head block from 0x200.
XFS (loop0): Starting recovery (logdev: internal)
==================================================================
BUG: KASAN: slab-out-of-bounds in xfs_btree_lookup_get_block+0x15c/0x6d0 fs/xfs/libxfs/xfs_btree.c:1813
Read of size 8 at addr ffff88807e89f258 by task syz-executor132/5074
CPU: 0 PID: 5074 Comm: syz-executor132 Not tainted 6.2.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1b1/0x290 lib/dump_stack.c:106
print_address_description+0x74/0x340 mm/kasan/report.c:306
print_report+0x107/0x1f0 mm/kasan/report.c:417
kasan_report+0xcd/0x100 mm/kasan/report.c:517
xfs_btree_lookup_get_block+0x15c/0x6d0 fs/xfs/libxfs/xfs_btree.c:1813
xfs_btree_lookup+0x346/0x12c0 fs/xfs/libxfs/xfs_btree.c:1913
xfs_btree_simple_query_range+0xde/0x6a0 fs/xfs/libxfs/xfs_btree.c:4713
xfs_btree_query_range+0x2db/0x380 fs/xfs/libxfs/xfs_btree.c:4953
xfs_refcount_recover_cow_leftovers+0x2d1/0xa60 fs/xfs/libxfs/xfs_refcount.c:1946
xfs_reflink_recover_cow+0xab/0x1b0 fs/xfs/xfs_reflink.c:930
xlog_recover_finish+0x824/0x920 fs/xfs/xfs_log_recover.c:3493
xfs_log_mount_finish+0x1ec/0x3d0 fs/xfs/xfs_log.c:829
xfs_mountfs+0x146a/0x1ef0 fs/xfs/xfs_mount.c:933
xfs_fs_fill_super+0xf95/0x11f0 fs/xfs/xfs_super.c:1666
get_tree_bdev+0x400/0x620 fs/super.c:1282
vfs_get_tree+0x88/0x270 fs/super.c:1489
do_new_mount+0x289/0xad0 fs/namespace.c:3145
do_mount fs/namespace.c:3488 [inline]
__do_sys_mount fs/namespace.c:3697 [inline]
__se_sys_mount+0x2d3/0x3c0 fs/namespace.c:3674
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f89fa3f4aca
Code: 83 c4 08 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffd5fb5ef8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00646975756f6e2c RCX: 00007f89fa3f4aca
RDX: 0000000020000100 RSI: 0000000020009640 RDI: 00007fffd5fb5f10
RBP: 00007fffd5fb5f10 R08: 00007fffd5fb5f50 R09: 000000000000970d
R10: 0000000000200800 R11: 0000000000000206 R12: 0000000000000004
R13: 0000555556c6b2c0 R14: 0000000000200800 R15: 00007fffd5fb5f50
</TASK>
The fuzzed image contains an AGF with an obviously garbage
agf_refcount_level value of 32, and a dirty log with a buffer log item
for that AGF. The ondisk AGF has a higher LSN than the recovered log
item. xlog_recover_buf_commit_pass2 reads the buffer, compares the
LSNs, and decides to skip replay because the ondisk buffer appears to be
newer.
Unfortunately, the ondisk buffer is corrupt, but recovery just read the
buffer with no buffer ops specified:
error = xfs_buf_read(mp->m_ddev_targp, buf_f->blf_blkno,
buf_f->blf_len, buf_flags, &bp, NULL);
Skipping the buffer leaves its contents in memory unverified. This sets
us up for a kernel crash because xfs_refcount_recover_cow_leftovers
reads the buffer (which is still around in XBF_DONE state, so no read
verification) and creates a refcountbt cursor of height 32. This is
impossible so we run off the end of the cursor object and crash.
Fix this by invoking the verifier on all skipped buffers and aborting
log recovery if the ondisk buffer is corrupt. It might be smarter to
force replay the log item atop the buffer and then see if it'll pass the
write verifier (like ext4 does) but for now let's go with the
conservative option where we stop immediately.
Link: https://syzkaller.appspot.com/bug?extid=7e9494b8b399902e994e
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Chandan Babu R <chandan.babu@oracle.com>
Acked-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c2407cf7d2 upstream.
Ever since commit 2a9127fcf2 ("mm: rewrite wait_on_page_bit_common()
logic") we've had some very occasional reports of BUG_ON(PageWriteback)
in write_cache_pages(), which we thought we already fixed in commit
073861ed77 ("mm: fix VM_BUG_ON(PageTail) and BUG_ON(PageWriteback)").
But syzbot just reported another one, even with that commit in place.
And it turns out that there's a simpler way to trigger the BUG_ON() than
the one Hugh found with page re-use. It all boils down to the fact that
the page writeback is ostensibly serialized by the page lock, but that
isn't actually really true.
Yes, the people _setting_ writeback all do so under the page lock, but
the actual clearing of the bit - and waking up any waiters - happens
without any page lock.
This gives us this fairly simple race condition:
CPU1 = end previous writeback
CPU2 = start new writeback under page lock
CPU3 = write_cache_pages()
CPU1 CPU2 CPU3
---- ---- ----
end_page_writeback()
test_clear_page_writeback(page)
... delayed...
lock_page();
set_page_writeback()
unlock_page()
lock_page()
wait_on_page_writeback();
wake_up_page(page, PG_writeback);
.. wakes up CPU3 ..
BUG_ON(PageWriteback(page));
where the BUG_ON() happens because we woke up the PG_writeback bit
becasue of the _previous_ writeback, but a new one had already been
started because the clearing of the bit wasn't actually atomic wrt the
actual wakeup or serialized by the page lock.
The reason this didn't use to happen was that the old logic in waiting
on a page bit would just loop if it ever saw the bit set again.
The nice proper fix would probably be to get rid of the whole "wait for
writeback to clear, and then set it" logic in the writeback path, and
replace it with an atomic "wait-to-set" (ie the same as we have for page
locking: we set the page lock bit with a single "lock_page()", not with
"wait for lock bit to clear and then set it").
However, out current model for writeback is that the waiting for the
writeback bit is done by the generic VFS code (ie write_cache_pages()),
but the actual setting of the writeback bit is done much later by the
filesystem ".writepages()" function.
IOW, to make the writeback bit have that same kind of "wait-to-set"
behavior as we have for page locking, we'd have to change our roughly
~50 different writeback functions. Painful.
Instead, just make "wait_on_page_writeback()" loop on the very unlikely
situation that the PG_writeback bit is still set, basically re-instating
the old behavior. This is very non-optimal in case of contention, but
since we only ever set the bit under the page lock, that situation is
controlled.
Reported-by: syzbot+2fc0712f8f8b8b8fa0ef@syzkaller.appspotmail.com
Fixes: 2a9127fcf2 ("mm: rewrite wait_on_page_bit_common() logic")
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 073861ed77 upstream.
Twice now, when exercising ext4 looped on shmem huge pages, I have crashed
on the PF_ONLY_HEAD check inside PageWaiters(): ext4_finish_bio() calling
end_page_writeback() calling wake_up_page() on tail of a shmem huge page,
no longer an ext4 page at all.
The problem is that PageWriteback is not accompanied by a page reference
(as the NOTE at the end of test_clear_page_writeback() acknowledges): as
soon as TestClearPageWriteback has been done, that page could be removed
from page cache, freed, and reused for something else by the time that
wake_up_page() is reached.
https://lore.kernel.org/linux-mm/20200827122019.GC14765@casper.infradead.org/
Matthew Wilcox suggested avoiding or weakening the PageWaiters() tail
check; but I'm paranoid about even looking at an unreferenced struct page,
lest its memory might itself have already been reused or hotremoved (and
wake_up_page_bit() may modify that memory with its ClearPageWaiters()).
Then on crashing a second time, realized there's a stronger reason against
that approach. If my testing just occasionally crashes on that check,
when the page is reused for part of a compound page, wouldn't it be much
more common for the page to get reused as an order-0 page before reaching
wake_up_page()? And on rare occasions, might that reused page already be
marked PageWriteback by its new user, and already be waited upon? What
would that look like?
It would look like BUG_ON(PageWriteback) after wait_on_page_writeback()
in write_cache_pages() (though I have never seen that crash myself).
Matthew Wilcox explaining this to himself:
"page is allocated, added to page cache, dirtied, writeback starts,
--- thread A ---
filesystem calls end_page_writeback()
test_clear_page_writeback()
--- context switch to thread B ---
truncate_inode_pages_range() finds the page, it doesn't have writeback set,
we delete it from the page cache. Page gets reallocated, dirtied, writeback
starts again. Then we call write_cache_pages(), see
PageWriteback() set, call wait_on_page_writeback()
--- context switch back to thread A ---
wake_up_page(page, PG_writeback);
... thread B is woken, but because the wakeup was for the old use of
the page, PageWriteback is still set.
Devious"
And prior to 2a9127fcf2 ("mm: rewrite wait_on_page_bit_common() logic")
this would have been much less likely: before that, wake_page_function()'s
non-exclusive case would stop walking and not wake if it found Writeback
already set again; whereas now the non-exclusive case proceeds to wake.
I have not thought of a fix that does not add a little overhead: the
simplest fix is for end_page_writeback() to get_page() before calling
test_clear_page_writeback(), then put_page() after wake_up_page().
Was there a chance of missed wakeups before, since a page freed before
reaching wake_up_page() would have PageWaiters cleared? I think not,
because each waiter does hold a reference on the page. This bug comes
when the old use of the page, the one we do TestClearPageWriteback on,
had *no* waiters, so no additional page reference beyond the page cache
(and whoever racily freed it). The reuse of the page has a waiter
holding a reference, and its own PageWriteback set; but the belated
wake_up_page() has woken the reuse to hit that BUG_ON(PageWriteback).
Reported-by: syzbot+3622cea378100f45d59f@syzkaller.appspotmail.com
Reported-by: Qian Cai <cai@lca.pw>
Fixes: 2a9127fcf2 ("mm: rewrite wait_on_page_bit_common() logic")
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: stable@vger.kernel.org # v5.8+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 85d38d5810 ]
When booting with "intremap=off" and "x2apic_phys" on the kernel command
line, the physical x2APIC driver ends up being used even when x2APIC
mode is disabled ("intremap=off" disables x2APIC mode). This happens
because the first compound condition check in x2apic_phys_probe() is
false due to x2apic_mode == 0 and so the following one returns true
after default_acpi_madt_oem_check() having already selected the physical
x2APIC driver.
This results in the following panic:
kernel BUG at arch/x86/kernel/apic/io_apic.c:2409!
invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.0-rc2-ver4.1rc2 #2
Hardware name: Dell Inc. PowerEdge R6515/07PXPY, BIOS 2.3.6 07/06/2021
RIP: 0010:setup_IO_APIC+0x9c/0xaf0
Call Trace:
<TASK>
? native_read_msr
apic_intr_mode_init
x86_late_time_init
start_kernel
x86_64_start_reservations
x86_64_start_kernel
secondary_startup_64_no_verify
</TASK>
which is:
setup_IO_APIC:
apic_printk(APIC_VERBOSE, "ENABLING IO-APIC IRQs\n");
for_each_ioapic(ioapic)
BUG_ON(mp_irqdomain_create(ioapic));
Return 0 to denote that x2APIC has not been enabled when probing the
physical x2APIC driver.
[ bp: Massage commit message heavily. ]
Fixes: 9ebd680bd0 ("x86, apic: Use probe routines to simplify apic selection")
Signed-off-by: Dheeraj Kumar Srivastava <dheerajkumar.srivastava@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Kishon Vijay Abraham I <kvijayab@amd.com>
Reviewed-by: Vasant Hegde <vasant.hegde@amd.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@gmail.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230616212236.1389-1-dheerajkumar.srivastava@amd.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
