Linux kernel
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When a binder transaction is initiated on a binder device coming from a
binderfs instance, a pointer to the name of the binder device is stashed
in the binder_transaction_log_entry's context_name member. Later on it
is used to print the name in print_binder_transaction_log_entry(). By
the time print_binder_transaction_log_entry() accesses context_name
binderfs_evict_inode() might have already freed the associated memory
thereby causing a UAF. Do the simple thing and prevent this by copying
the name of the binder device instead of stashing a pointer to it.
Reported-by: Jann Horn <jannh@google.com>
Fixes: 03e2e07e3814 ("binder: Make transaction_log available in binderfs")
Link: https://lore.kernel.org/r/CAG48ez14Q0-F8LqsvcNbyR2o6gPW8SHXsm4u5jmD9MpsteM2Tw@mail.gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Acked-by: Todd Kjos <tkjos@google.com>
Reviewed-by: Hridya Valsaraju <hridya@google.com>
Link: https://lore.kernel.org/r/20191008130159.10161-1-christian.brauner@ubuntu.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In fastrpc_dma_buf_attach if dma_get_sgtable fails the allocated memory
for a should be released.
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Link: https://lore.kernel.org/r/20190925152742.16258-1-navid.emamdoost@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The fixed MKHI client on PCH 6 gen platforms
does not support fw version retrieval.
The error is not fatal, but it fills up the kernel logs and
slows down the driver start.
This patch disables requesting FW version on GEN6 and earlier platforms.
Fixes warning:
[ 15.964298] mei mei::55213584-9a29-4916-badf-0fb7ed682aeb:01: Could not read FW version
[ 15.964301] mei mei::55213584-9a29-4916-badf-0fb7ed682aeb:01: version command failed -5
Cc: <stable@vger.kernel.org> +v4.18
Cc: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20191004181722.31374-1-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add Comet Point devices IDs for Comet Lake U platforms.
Cc: <stable@vger.kernel.org>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20191001235958.19979-1-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull btrfs fixes from David Sterba:
"A bunch of fixes that accumulated in recent weeks, mostly material for
stable.
Summary:
- fix for regression from 5.3 that prevents to use balance convert
with single profile
- qgroup fixes: rescan race, accounting leak with multiple writers,
potential leak after io failure recovery
- fix for use after free in relocation (reported by KASAN)
- other error handling fixups"
* tag 'for-5.4-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: qgroup: Fix reserved data space leak if we have multiple reserve calls
btrfs: qgroup: Fix the wrong target io_tree when freeing reserved data space
btrfs: Fix a regression which we can't convert to SINGLE profile
btrfs: relocation: fix use-after-free on dead relocation roots
Btrfs: fix race setting up and completing qgroup rescan workers
Btrfs: fix missing error return if writeback for extent buffer never started
btrfs: adjust dirty_metadata_bytes after writeback failure of extent buffer
Btrfs: fix selftests failure due to uninitialized i_mode in test inodes
Pull csky updates from Guo Ren:
"This round of csky subsystem just some fixups:
- Fix mb() synchronization problem
- Fix dma_alloc_coherent with PAGE_SO attribute
- Fix cache_op failed when cross memory ZONEs
- Optimize arch_sync_dma_for_cpu/device with dma_inv_range
- Fix ioremap function losing
- Fix arch_get_unmapped_area() implementation
- Fix defer cache flush for 610
- Support kernel non-aligned access
- Fix 610 vipt cache flush mechanism
- Fix add zero_fp fixup perf backtrace panic
- Move static keyword to the front of declaration
- Fix csky_pmu.max_period assignment
- Use generic free_initrd_mem()
- entry: Remove unneeded need_resched() loop"
* tag 'csky-for-linus-5.4-rc1' of git://github.com/c-sky/csky-linux:
csky: Move static keyword to the front of declaration
csky: entry: Remove unneeded need_resched() loop
csky: Fixup csky_pmu.max_period assignment
csky: Fixup add zero_fp fixup perf backtrace panic
csky: Use generic free_initrd_mem()
csky: Fixup 610 vipt cache flush mechanism
csky: Support kernel non-aligned access
csky: Fixup defer cache flush for 610
csky: Fixup arch_get_unmapped_area() implementation
csky: Fixup ioremap function losing
csky: Optimize arch_sync_dma_for_cpu/device with dma_inv_range
csky/dma: Fixup cache_op failed when cross memory ZONEs
csky: Fixup dma_alloc_coherent with PAGE_SO attribute
csky: Fixup mb() synchronization problem
[BUG]
The following script can cause btrfs qgroup data space leak:
mkfs.btrfs -f $dev
mount $dev -o nospace_cache $mnt
btrfs subv create $mnt/subv
btrfs quota en $mnt
btrfs quota rescan -w $mnt
btrfs qgroup limit 128m $mnt/subv
for (( i = 0; i < 3; i++)); do
# Create 3 64M holes for latter fallocate to fail
truncate -s 192m $mnt/subv/file
xfs_io -c "pwrite 64m 4k" $mnt/subv/file > /dev/null
xfs_io -c "pwrite 128m 4k" $mnt/subv/file > /dev/null
sync
# it's supposed to fail, and each failure will leak at least 64M
# data space
xfs_io -f -c "falloc 0 192m" $mnt/subv/file &> /dev/null
rm $mnt/subv/file
sync
done
# Shouldn't fail after we removed the file
xfs_io -f -c "falloc 0 64m" $mnt/subv/file
[CAUSE]
Btrfs qgroup data reserve code allow multiple reservations to happen on
a single extent_changeset:
E.g:
btrfs_qgroup_reserve_data(inode, &data_reserved, 0, SZ_1M);
btrfs_qgroup_reserve_data(inode, &data_reserved, SZ_1M, SZ_2M);
btrfs_qgroup_reserve_data(inode, &data_reserved, 0, SZ_4M);
Btrfs qgroup code has its internal tracking to make sure we don't
double-reserve in above example.
The only pattern utilizing this feature is in the main while loop of
btrfs_fallocate() function.
However btrfs_qgroup_reserve_data()'s error handling has a bug in that
on error it clears all ranges in the io_tree with EXTENT_QGROUP_RESERVED
flag but doesn't free previously reserved bytes.
This bug has a two fold effect:
- Clearing EXTENT_QGROUP_RESERVED ranges
This is the correct behavior, but it prevents
btrfs_qgroup_check_reserved_leak() to catch the leakage as the
detector is purely EXTENT_QGROUP_RESERVED flag based.
- Leak the previously reserved data bytes.
The bug manifests when N calls to btrfs_qgroup_reserve_data are made and
the last one fails, leaking space reserved in the previous ones.
[FIX]
Also free previously reserved data bytes when btrfs_qgroup_reserve_data
fails.
Fixes: 524725537023 ("btrfs: qgroup: Introduce btrfs_qgroup_reserve_data function")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull ARM SoC fixes from Olof Johansson:
"A few fixes that have trickled in through the merge window:
- Video fixes for OMAP due to panel-dpi driver removal
- Clock fixes for OMAP that broke no-idle quirks + nfsroot on DRA7
- Fixing arch version on ASpeed ast2500
- Two fixes for reset handling on ARM SCMI"
* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
ARM: aspeed: ast2500 is ARMv6K
reset: reset-scmi: add missing handle initialisation
firmware: arm_scmi: reset: fix reset_state assignment in scmi_domain_reset
bus: ti-sysc: Remove unpaired sysc_clkdm_deny_idle()
ARM: dts: logicpd-som-lv: Fix i2c2 and i2c3 Pin mux
ARM: dts: am3517-evm: Fix missing video
ARM: dts: logicpd-torpedo-baseboard: Fix missing video
ARM: omap2plus_defconfig: Fix missing video
bus: ti-sysc: Fix handling of invalid clocks
bus: ti-sysc: Fix clock handling for no-idle quirks
Move the static keyword to the front of declaration of
csky_pmu_of_device_ids, and resolve the following compiler
warning that can be seen when building with warnings
enabled (W=1):
arch/csky/kernel/perf_event.c:1340:1: warning:
‘static’ is not at beginning of declaration [-Wold-style-declaration]
Signed-off-by: Krzysztof Wilczynski <kw@linux.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
[BUG]
Under the following case with qgroup enabled, if some error happened
after we have reserved delalloc space, then in error handling path, we
could cause qgroup data space leakage:
From btrfs_truncate_block() in inode.c:
ret = btrfs_delalloc_reserve_space(inode, &data_reserved,
block_start, blocksize);
if (ret)
goto out;
again:
page = find_or_create_page(mapping, index, mask);
if (!page) {
btrfs_delalloc_release_space(inode, data_reserved,
block_start, blocksize, true);
btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize, true);
ret = -ENOMEM;
goto out;
}
[CAUSE]
In the above case, btrfs_delalloc_reserve_space() will call
btrfs_qgroup_reserve_data() and mark the io_tree range with
EXTENT_QGROUP_RESERVED flag.
In the error handling path, we have the following call stack:
btrfs_delalloc_release_space()
|- btrfs_free_reserved_data_space()
|- btrsf_qgroup_free_data()
|- __btrfs_qgroup_release_data(reserved=@reserved, free=1)
|- qgroup_free_reserved_data(reserved=@reserved)
|- clear_record_extent_bits();
|- freed += changeset.bytes_changed;
However due to a completion bug, qgroup_free_reserved_data() will clear
EXTENT_QGROUP_RESERVED flag in BTRFS_I(inode)->io_failure_tree, other
than the correct BTRFS_I(inode)->io_tree.
Since io_failure_tree is never marked with that flag,
btrfs_qgroup_free_data() will not free any data reserved space at all,
causing a leakage.
This type of error handling can only be triggered by errors outside of
qgroup code. So EDQUOT error from qgroup can't trigger it.
[FIX]
Fix the wrong target io_tree.
Reported-by: Josef Bacik <josef@toxicpanda.com>
Fixes: bc42bda22345 ("btrfs: qgroup: Fix qgroup reserved space underflow by only freeing reserved ranges")
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull tracing fixes from Steven Rostedt:
"A few more tracing fixes:
- Fix a buffer overflow by checking nr_args correctly in probes
- Fix a warning that is reported by clang
- Fix a possible memory leak in error path of filter processing
- Fix the selftest that checks for failures, but wasn't failing
- Minor clean up on call site output of a memory trace event"
* tag 'trace-v5.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
selftests/ftrace: Fix same probe error test
mm, tracing: Print symbol name for call_site in trace events
tracing: Have error path in predicate_parse() free its allocated memory
tracing: Fix clang -Wint-in-bool-context warnings in IF_ASSIGN macro
tracing/probe: Fix to check the difference of nr_args before adding probe
Fixes for omap variants
Few fixes for ti-sysc interconnect target module driver for no-idle
quirks that caused nfsroot to fail on some dra7 boards.
And let's fixes to get LCD working again for logicpd board that got
broken a while back with removal of panel-dpi driver. We need to now
use generic CONFIG_DRM_PANEL_SIMPLE instead.
* tag 'fixes-5.4-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
bus: ti-sysc: Remove unpaired sysc_clkdm_deny_idle()
ARM: dts: logicpd-som-lv: Fix i2c2 and i2c3 Pin mux
ARM: dts: am3517-evm: Fix missing video
ARM: dts: logicpd-torpedo-baseboard: Fix missing video
ARM: omap2plus_defconfig: Fix missing video
bus: ti-sysc: Fix handling of invalid clocks
bus: ti-sysc: Fix clock handling for no-idle quirks
Link: https://lore.kernel.org/r/pull-1568819401-72461@atomide.com
Signed-off-by: Olof Johansson <olof@lixom.net>