[ Upstream commit 3a17f23f7c ]
Executing dql_reset after setting a non-zero value for limit_min can
lead to an unreasonable situation where dql->limit is less than
dql->limit_min.
For instance, after setting
/sys/class/net/eth*/queues/tx-0/byte_queue_limits/limit_min,
an ifconfig down/up operation might cause the ethernet driver to call
netdev_tx_reset_queue, which in turn invokes dql_reset.
In this case, dql->limit is reset to 0 while dql->limit_min remains
non-zero value, which is unexpected. The limit should always be
greater than or equal to limit_min.
Signed-off-by: Jing Su <jingsusu@didiglobal.com>
Link: https://patch.msgid.link/Z9qHD1s/NEuQBdgH@pilot-ThinkCentre-M930t-N000
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 8b46fdaea8 upstream.
The split_sg_phys function was incorrectly setting the offsets of all
scatterlist entries (except the first) to 0. Only the first scatterlist
entry's offset and length needs to be modified to account for the skip.
Setting the rest entries' offsets to 0 could lead to incorrect data
access.
I am using this function in a crypto driver that I'm currently developing
(not yet sent to mailing list). During testing, it was observed that the
output scatterlists (except the first one) contained incorrect garbage
data.
I narrowed this issue down to the call of sg_split(). Upon debugging
inside this function, I found that this resetting of offset is the cause
of the problem, causing the subsequent scatterlists to point to incorrect
memory locations in a page. By removing this code, I am obtaining
expected data in all the split output scatterlists. Thus, this was indeed
causing observable runtime effects!
This patch removes the offending code, ensuring that the page offsets in
the input scatterlist are preserved in the output scatterlist.
Link: https://lkml.kernel.org/r/20250319111437.1969903-1-t-pratham@ti.com
Fixes: f8bcbe62ac ("lib: scatterlist: add sg splitting function")
Signed-off-by: T Pratham <t-pratham@ti.com>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kamlesh Gurudasani <kamlesh@ti.com>
Cc: Praneeth Bajjuri <praneeth@ti.com>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit af324dc0e2 ]
The static code analysis tool "Coverity Scan" pointed the following
implementation details out for further development considerations:
CID 1309755: Unused value
In sw842_compress: A value assigned to a variable is never used. (CWE-563)
returned_value: Assigning value from add_repeat_template(p, repeat_count)
to ret here, but that stored value is overwritten before it can be used.
Conclusion:
Add error handling for the return value from an add_repeat_template()
call.
Fixes: 2da572c959 ("lib: add software 842 compression/decompression")
Signed-off-by: Tanya Agarwal <tanyaagarwal25699@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 684d28feb8 upstream.
fill_pool() uses 'obj_pool_min_free' to decide whether objects should be
handed back to the kmem cache. But 'obj_pool_min_free' records the lowest
historical value of the number of objects in the object pool and not the
minimum number of objects which should be kept in the pool.
Use 'debug_objects_pool_min_level' instead, which holds the minimum number
which was scaled to the number of CPUs at boot time.
[ tglx: Massage change log ]
Fixes: d26bf5056f ("debugobjects: Reduce number of pool_lock acquisitions in fill_pool()")
Fixes: 36c4ead6f6 ("debugobjects: Add global free list and the counter")
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240904133944.2124-3-thunder.leizhen@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit b2f11c6f3e ]
If we need to increase the tree depth, allocate a new node, and then
race with another thread that increased the tree depth before us, we'll
still have a preallocated node that might be used later.
If we then use that node for a new non-root node, it'll still have a
pointer to the old root instead of being zeroed - fix this by zeroing it
in the cmpxchg failure path.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit e1be43d9b5 upstream.
In order to perform more open-coded replacements of common allocation
size arithmetic, the kernel needs saturating (SIZE_MAX) helpers for
multiplication, addition, and subtraction. For example, it is common in
allocators, especially on realloc, to add to an existing size:
p = krealloc(map->patch,
sizeof(struct reg_sequence) * (map->patch_regs + num_regs),
GFP_KERNEL);
There is no existing saturating replacement for this calculation, and
just leaving the addition open coded inside array_size() could
potentially overflow as well. For example, an overflow in an expression
for a size_t argument might wrap to zero:
array_size(anything, something_at_size_max + 1) == 0
Introduce size_mul(), size_add(), and size_sub() helpers that
implicitly promote arguments to size_t and saturated calculations for
use in allocations. With these helpers it is also possible to redefine
array_size(), array3_size(), flex_array_size(), and struct_size() in
terms of the new helpers.
As with the check_*_overflow() helpers, the new helpers use __must_check,
though what is really desired is a way to make sure that assignment is
only to a size_t lvalue. Without this, it's still possible to introduce
overflow/underflow via type conversion (i.e. from size_t to int).
Enforcing this will currently need to be left to static analysis or
future use of -Wconversion.
Additionally update the overflow unit tests to force runtime evaluation
for the pathological cases.
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Len Baker <len.baker@gmx.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a37fbe666c upstream.
The number of times yet another open coded
`BITS_TO_LONGS(nbits) * sizeof(long)` can be spotted is huge.
Some generic helper is long overdue.
Add one, bitmap_size(), but with one detail.
BITS_TO_LONGS() uses DIV_ROUND_UP(). The latter works well when both
divident and divisor are compile-time constants or when the divisor
is not a pow-of-2. When it is however, the compilers sometimes tend
to generate suboptimal code (GCC 13):
48 83 c0 3f add $0x3f,%rax
48 c1 e8 06 shr $0x6,%rax
48 8d 14 c5 00 00 00 00 lea 0x0(,%rax,8),%rdx
%BITS_PER_LONG is always a pow-2 (either 32 or 64), but GCC still does
full division of `nbits + 63` by it and then multiplication by 8.
Instead of BITS_TO_LONGS(), use ALIGN() and then divide by 8. GCC:
8d 50 3f lea 0x3f(%rax),%edx
c1 ea 03 shr $0x3,%edx
81 e2 f8 ff ff 1f and $0x1ffffff8,%edx
Now it shifts `nbits + 63` by 3 positions (IOW performs fast division
by 8) and then masks bits[2:0]. bloat-o-meter:
add/remove: 0/0 grow/shrink: 20/133 up/down: 156/-773 (-617)
Clang does it better and generates the same code before/after starting
from -O1, except that with the ALIGN() approach it uses %edx and thus
still saves some bytes:
add/remove: 0/0 grow/shrink: 9/133 up/down: 18/-538 (-520)
Note that we can't expand DIV_ROUND_UP() by adding a check and using
this approach there, as it's used in array declarations where
expressions are not allowed.
Add this helper to tools/ as well.
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Acked-by: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 97d833ceb2 ]
ACLs in Spectrum-2 and newer ASICs can reside in the algorithmic TCAM
(A-TCAM) or in the ordinary circuit TCAM (C-TCAM). The former can
contain more ACLs (i.e., tc filters), but the number of masks in each
region (i.e., tc chain) is limited.
In order to mitigate the effects of the above limitation, the device
allows filters to share a single mask if their masks only differ in up
to 8 consecutive bits. For example, dst_ip/25 can be represented using
dst_ip/24 with a delta of 1 bit. The C-TCAM does not have a limit on the
number of masks being used (and therefore does not support mask
aggregation), but can contain a limited number of filters.
The driver uses the "objagg" library to perform the mask aggregation by
passing it objects that consist of the filter's mask and whether the
filter is to be inserted into the A-TCAM or the C-TCAM since filters in
different TCAMs cannot share a mask.
The set of created objects is dependent on the insertion order of the
filters and is not necessarily optimal. Therefore, the driver will
periodically ask the library to compute a more optimal set ("hints") by
looking at all the existing objects.
When the library asks the driver whether two objects can be aggregated
the driver only compares the provided masks and ignores the A-TCAM /
C-TCAM indication. This is the right thing to do since the goal is to
move as many filters as possible to the A-TCAM. The driver also forbids
two identical masks from being aggregated since this can only happen if
one was intentionally put in the C-TCAM to avoid a conflict in the
A-TCAM.
The above can result in the following set of hints:
H1: {mask X, A-TCAM} -> H2: {mask Y, A-TCAM} // X is Y + delta
H3: {mask Y, C-TCAM} -> H4: {mask Z, A-TCAM} // Y is Z + delta
After getting the hints from the library the driver will start migrating
filters from one region to another while consulting the computed hints
and instructing the device to perform a lookup in both regions during
the transition.
Assuming a filter with mask X is being migrated into the A-TCAM in the
new region, the hints lookup will return H1. Since H2 is the parent of
H1, the library will try to find the object associated with it and
create it if necessary in which case another hints lookup (recursive)
will be performed. This hints lookup for {mask Y, A-TCAM} will either
return H2 or H3 since the driver passes the library an object comparison
function that ignores the A-TCAM / C-TCAM indication.
This can eventually lead to nested objects which are not supported by
the library [1].
Fix by removing the object comparison function from both the driver and
the library as the driver was the only user. That way the lookup will
only return exact matches.
I do not have a reliable reproducer that can reproduce the issue in a
timely manner, but before the fix the issue would reproduce in several
minutes and with the fix it does not reproduce in over an hour.
Note that the current usefulness of the hints is limited because they
include the C-TCAM indication and represent aggregation that cannot
actually happen. This will be addressed in net-next.
[1]
WARNING: CPU: 0 PID: 153 at lib/objagg.c:170 objagg_obj_parent_assign+0xb5/0xd0
Modules linked in:
CPU: 0 PID: 153 Comm: kworker/0:18 Not tainted 6.9.0-rc6-custom-g70fbc2c1c38b #42
Hardware name: Mellanox Technologies Ltd. MSN3700C/VMOD0008, BIOS 5.11 10/10/2018
Workqueue: mlxsw_core mlxsw_sp_acl_tcam_vregion_rehash_work
RIP: 0010:objagg_obj_parent_assign+0xb5/0xd0
[...]
Call Trace:
<TASK>
__objagg_obj_get+0x2bb/0x580
objagg_obj_get+0xe/0x80
mlxsw_sp_acl_erp_mask_get+0xb5/0xf0
mlxsw_sp_acl_atcam_entry_add+0xe8/0x3c0
mlxsw_sp_acl_tcam_entry_create+0x5e/0xa0
mlxsw_sp_acl_tcam_vchunk_migrate_one+0x16b/0x270
mlxsw_sp_acl_tcam_vregion_rehash_work+0xbe/0x510
process_one_work+0x151/0x370
Fixes: 9069a3817d ("lib: objagg: implement optimization hints assembly and use hints for object creation")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Amit Cohen <amcohen@nvidia.com>
Tested-by: Alexander Zubkov <green@qrator.net>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b4a3a89fff ]
The library supports aggregation of objects into other objects only if
the parent object does not have a parent itself. That is, nesting is not
supported.
Aggregation happens in two cases: Without and with hints, where hints
are a pre-computed recommendation on how to aggregate the provided
objects.
Nesting is not possible in the first case due to a check that prevents
it, but in the second case there is no check because the assumption is
that nesting cannot happen when creating objects based on hints. The
violation of this assumption leads to various warnings and eventually to
a general protection fault [1].
Before fixing the root cause, error out when nesting happens and warn.
[1]
general protection fault, probably for non-canonical address 0xdead000000000d90: 0000 [#1] PREEMPT SMP PTI
CPU: 1 PID: 1083 Comm: kworker/1:9 Tainted: G W 6.9.0-rc6-custom-gd9b4f1cca7fb #7
Hardware name: Mellanox Technologies Ltd. MSN3700/VMOD0005, BIOS 5.11 01/06/2019
Workqueue: mlxsw_core mlxsw_sp_acl_tcam_vregion_rehash_work
RIP: 0010:mlxsw_sp_acl_erp_bf_insert+0x25/0x80
[...]
Call Trace:
<TASK>
mlxsw_sp_acl_atcam_entry_add+0x256/0x3c0
mlxsw_sp_acl_tcam_entry_create+0x5e/0xa0
mlxsw_sp_acl_tcam_vchunk_migrate_one+0x16b/0x270
mlxsw_sp_acl_tcam_vregion_rehash_work+0xbe/0x510
process_one_work+0x151/0x370
worker_thread+0x2cb/0x3e0
kthread+0xd0/0x100
ret_from_fork+0x34/0x50
ret_from_fork_asm+0x1a/0x30
</TASK>
Fixes: 9069a3817d ("lib: objagg: implement optimization hints assembly and use hints for object creation")
Reported-by: Alexander Zubkov <green@qrator.net>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Amit Cohen <amcohen@nvidia.com>
Tested-by: Alexander Zubkov <green@qrator.net>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 843a8851e8 ]
lib/test_blackhole_dev.c sets a variable that is never read, causing
this following building warning:
lib/test_blackhole_dev.c:32:17: warning: variable 'ethh' set but not used [-Wunused-but-set-variable]
Remove the variable struct ethhdr *ethh, which is unused.
Fixes: 509e56b37c ("blackhole_dev: add a selftest")
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit af73483f4e ]
The IDA usually detects double-frees, but that detection failed to
consider the case when there are no nearby IDs allocated and so we have a
NULL bitmap rather than simply having a clear bit. Add some tests to the
test-suite to be sure we don't inadvertently reintroduce this problem.
Unfortunately they're quite noisy so include a message to disregard
the warnings.
Reported-by: Zhenghan Wang <wzhmmmmm@gmail.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 3bb2a01caa upstream.
In kobject_get_path(), if kobj->name is changed between calls
get_kobj_path_length() and fill_kobj_path() and the length becomes
longer, then fill_kobj_path() will have an out-of-bounds bug.
The actual current problem occurs when the ixgbe probe.
In ixgbe_mii_bus_init(), if the length of netdev->dev.kobj.name
length becomes longer, out-of-bounds will occur.
cpu0 cpu1
ixgbe_probe
register_netdev(netdev)
netdev_register_kobject
device_add
kobject_uevent // Sending ADD events
systemd-udevd // rename netdev
dev_change_name
device_rename
kobject_rename
ixgbe_mii_bus_init |
mdiobus_register |
__mdiobus_register |
device_register |
device_add |
kobject_uevent |
kobject_get_path |
len = get_kobj_path_length // old name |
path = kzalloc(len, gfp_mask); |
kobj->name = name;
/* name length becomes
* longer
*/
fill_kobj_path /* kobj path length is
* longer than path,
* resulting in out of
* bounds when filling path
*/
This is the kasan report:
==================================================================
BUG: KASAN: slab-out-of-bounds in fill_kobj_path+0x50/0xc0
Write of size 7 at addr ff1100090573d1fd by task kworker/28:1/673
Workqueue: events work_for_cpu_fn
Call Trace:
<TASK>
dump_stack_lvl+0x34/0x48
print_address_description.constprop.0+0x86/0x1e7
print_report+0x36/0x4f
kasan_report+0xad/0x130
kasan_check_range+0x35/0x1c0
memcpy+0x39/0x60
fill_kobj_path+0x50/0xc0
kobject_get_path+0x5a/0xc0
kobject_uevent_env+0x140/0x460
device_add+0x5c7/0x910
__mdiobus_register+0x14e/0x490
ixgbe_probe.cold+0x441/0x574 [ixgbe]
local_pci_probe+0x78/0xc0
work_for_cpu_fn+0x26/0x40
process_one_work+0x3b6/0x6a0
worker_thread+0x368/0x520
kthread+0x165/0x1a0
ret_from_fork+0x1f/0x30
This reproducer triggers that bug:
while:
do
rmmod ixgbe
sleep 0.5
modprobe ixgbe
sleep 0.5
When calling fill_kobj_path() to fill path, if the name length of
kobj becomes longer, return failure and retry. This fixes the problem.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Link: https://lore.kernel.org/r/20221220012143.52141-1-wanghai38@huawei.com
Signed-off-by: Oleksandr Tymoshenko <ovt@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit efb78fa86e ("lib/test_meminit: allocate pages up to order
MAX_ORDER") works great in kernels 6.4 and newer thanks to commit
23baf831a3 ("mm, treewide: redefine MAX_ORDER sanely"), but for older
kernels, the loop is off by one, which causes crashes when the test
runs.
Fix this up by changing "<= MAX_ORDER" "< MAX_ORDER" to allow the test
to work properly for older kernel branches.
Fixes: cbfffe5122 ("lib/test_meminit: allocate pages up to order MAX_ORDER")
Cc: Andrew Donnellan <ajd@linux.ibm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Xiaoke Wang <xkernel.wang@foxmail.com>
Cc: <stable@vger.kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 4d0fe8c52b ]
When I register a kset in the following way:
static struct kset my_kset;
kobject_set_name(&my_kset.kobj, "my_kset");
ret = kset_register(&my_kset);
A null pointer dereference exception is occurred:
[ 4453.568337] Unable to handle kernel NULL pointer dereference at \
virtual address 0000000000000028
... ...
[ 4453.810361] Call trace:
[ 4453.813062] kobject_get_ownership+0xc/0x34
[ 4453.817493] kobject_add_internal+0x98/0x274
[ 4453.822005] kset_register+0x5c/0xb4
[ 4453.825820] my_kobj_init+0x44/0x1000 [my_kset]
... ...
Because I didn't initialize my_kset.kobj.ktype.
According to the description in Documentation/core-api/kobject.rst:
- A ktype is the type of object that embeds a kobject. Every structure
that embeds a kobject needs a corresponding ktype.
So add sanity check to make sure kset->kobj.ktype is not NULL.
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Link: https://lore.kernel.org/r/20230805084114.1298-2-thunder.leizhen@huaweicloud.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9e47a758b7 ]
During NVMeTCP Authentication a controller can trigger a kernel
oops by specifying the 8192 bit Diffie Hellman group and passing
a correctly sized, but zeroed Diffie Hellamn value.
mpi_cmp_ui() was detecting this if the second parameter was 0,
but 1 is passed from dh_is_pubkey_valid(). This causes the null
pointer u->d to be dereferenced towards the end of mpi_cmp_ui()
Signed-off-by: Mark O'Donovan <shiftee@posteo.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit efb78fa86e upstream.
test_pages() tests the page allocator by calling alloc_pages() with
different orders up to order 10.
However, different architectures and platforms support different maximum
contiguous allocation sizes. The default maximum allocation order
(MAX_ORDER) is 10, but architectures can use CONFIG_ARCH_FORCE_MAX_ORDER
to override this. On platforms where this is less than 10, test_meminit()
will blow up with a WARN(). This is expected, so let's not do that.
Replace the hardcoded "10" with the MAX_ORDER macro so that we test
allocations up to the expected platform limit.
Link: https://lkml.kernel.org/r/20230714015238.47931-1-ajd@linux.ibm.com
Fixes: 5015a300a5 ("lib: introduce test_meminit module")
Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Xiaoke Wang <xkernel.wang@foxmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 382d4cd184 upstream.
The gcc compiler translates on some architectures the 64-bit
__builtin_clzll() function to a call to the libgcc function __clzdi2(),
which should take a 64-bit parameter on 32- and 64-bit platforms.
But in the current kernel code, the built-in __clzdi2() function is
defined to operate (wrongly) on 32-bit parameters if BITS_PER_LONG ==
32, thus the return values on 32-bit kernels are in the range from
[0..31] instead of the expected [0..63] range.
This patch fixes the in-kernel functions __clzdi2() and __ctzdi2() to
take a 64-bit parameter on 32-bit kernels as well, thus it makes the
functions identical for 32- and 64-bit kernels.
This bug went unnoticed since kernel 3.11 for over 10 years, and here
are some possible reasons for that:
a) Some architectures have assembly instructions to count the bits and
which are used instead of calling __clzdi2(), e.g. on x86 the bsr
instruction and on ppc cntlz is used. On such architectures the
wrong __clzdi2() implementation isn't used and as such the bug has
no effect and won't be noticed.
b) Some architectures link to libgcc.a, and the in-kernel weak
functions get replaced by the correct 64-bit variants from libgcc.a.
c) __builtin_clzll() and __clzdi2() doesn't seem to be used in many
places in the kernel, and most likely only in uncritical functions,
e.g. when printing hex values via seq_put_hex_ll(). The wrong return
value will still print the correct number, but just in a wrong
formatting (e.g. with too many leading zeroes).
d) 32-bit kernels aren't used that much any longer, so they are less
tested.
A trivial testcase to verify if the currently running 32-bit kernel is
affected by the bug is to look at the output of /proc/self/maps:
Here the kernel uses a correct implementation of __clzdi2():
root@debian:~# cat /proc/self/maps
00010000-00019000 r-xp 00000000 08:05 787324 /usr/bin/cat
00019000-0001a000 rwxp 00009000 08:05 787324 /usr/bin/cat
0001a000-0003b000 rwxp 00000000 00:00 0 [heap]
f7551000-f770d000 r-xp 00000000 08:05 794765 /usr/lib/hppa-linux-gnu/libc.so.6
...
and this kernel uses the broken implementation of __clzdi2():
root@debian:~# cat /proc/self/maps
0000000010000-0000000019000 r-xp 00000000 000000008:000000005 787324 /usr/bin/cat
0000000019000-000000001a000 rwxp 000000009000 000000008:000000005 787324 /usr/bin/cat
000000001a000-000000003b000 rwxp 00000000 00:00 0 [heap]
00000000f73d1000-00000000f758d000 r-xp 00000000 000000008:000000005 794765 /usr/lib/hppa-linux-gnu/libc.so.6
...
Signed-off-by: Helge Deller <deller@gmx.de>
Fixes: 4df87bb7b6 ("lib: add weak clz/ctz functions")
Cc: Chanho Min <chanho.min@lge.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@vger.kernel.org # v3.11+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7dae593cd2 upstream.
In a couple of situations like
name = kstrndup(buf, count, GFP_KERNEL);
if (!name)
return -ENOSPC;
the error is not actually "No space left on device", but "Out of memory".
It is semantically correct to return -ENOMEM in all failed kstrndup()
and kzalloc() cases in this driver, as it is not a problem with disk
space, but with kernel memory allocator failing allocation.
The semantically correct should be:
name = kstrndup(buf, count, GFP_KERNEL);
if (!name)
return -ENOMEM;
Cc: Dan Carpenter <error27@gmail.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Luis R. Rodriguez" <mcgrof@ruslug.rutgers.edu>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Brian Norris <briannorris@chromium.org>
Fixes: c92316bf8e ("test_firmware: add batched firmware tests")
Fixes: 0a8adf5847 ("test: add firmware_class loader test")
Fixes: 548193cba2 ("test_firmware: add support for firmware_request_platform")
Fixes: eb910947c8 ("test: firmware_class: add asynchronous request trigger")
Fixes: 061132d2b9 ("test_firmware: add test custom fallback trigger")
Fixes: 7feebfa487 ("test_firmware: add support for request_firmware_into_buf")
Signed-off-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Message-ID: <20230606070808.9300-1-mirsad.todorovac@alu.unizg.hr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4acfe3dfde upstream.
Dan Carpenter spotted a race condition in a couple of situations like
these in the test_firmware driver:
static int test_dev_config_update_u8(const char *buf, size_t size, u8 *cfg)
{
u8 val;
int ret;
ret = kstrtou8(buf, 10, &val);
if (ret)
return ret;
mutex_lock(&test_fw_mutex);
*(u8 *)cfg = val;
mutex_unlock(&test_fw_mutex);
/* Always return full write size even if we didn't consume all */
return size;
}
static ssize_t config_num_requests_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
int rc;
mutex_lock(&test_fw_mutex);
if (test_fw_config->reqs) {
pr_err("Must call release_all_firmware prior to changing config\n");
rc = -EINVAL;
mutex_unlock(&test_fw_mutex);
goto out;
}
mutex_unlock(&test_fw_mutex);
rc = test_dev_config_update_u8(buf, count,
&test_fw_config->num_requests);
out:
return rc;
}
static ssize_t config_read_fw_idx_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
return test_dev_config_update_u8(buf, count,
&test_fw_config->read_fw_idx);
}
The function test_dev_config_update_u8() is called from both the locked
and the unlocked context, function config_num_requests_store() and
config_read_fw_idx_store() which can both be called asynchronously as
they are driver's methods, while test_dev_config_update_u8() and siblings
change their argument pointed to by u8 *cfg or similar pointer.
To avoid deadlock on test_fw_mutex, the lock is dropped before calling
test_dev_config_update_u8() and re-acquired within test_dev_config_update_u8()
itself, but alas this creates a race condition.
Having two locks wouldn't assure a race-proof mutual exclusion.
This situation is best avoided by the introduction of a new, unlocked
function __test_dev_config_update_u8() which can be called from the locked
context and reducing test_dev_config_update_u8() to:
static int test_dev_config_update_u8(const char *buf, size_t size, u8 *cfg)
{
int ret;
mutex_lock(&test_fw_mutex);
ret = __test_dev_config_update_u8(buf, size, cfg);
mutex_unlock(&test_fw_mutex);
return ret;
}
doing the locking and calling the unlocked primitive, which enables both
locked and unlocked versions without duplication of code.
The similar approach was applied to all functions called from the locked
and the unlocked context, which safely mitigates both deadlocks and race
conditions in the driver.
__test_dev_config_update_bool(), __test_dev_config_update_u8() and
__test_dev_config_update_size_t() unlocked versions of the functions
were introduced to be called from the locked contexts as a workaround
without releasing the main driver's lock and thereof causing a race
condition.
The test_dev_config_update_bool(), test_dev_config_update_u8() and
test_dev_config_update_size_t() locked versions of the functions
are being called from driver methods without the unnecessary multiplying
of the locking and unlocking code for each method, and complicating
the code with saving of the return value across lock.
Fixes: 7feebfa487 ("test_firmware: add support for request_firmware_into_buf")
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Russ Weight <russell.h.weight@intel.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Tianfei Zhang <tianfei.zhang@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Colin Ian King <colin.i.king@gmail.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: linux-kselftest@vger.kernel.org
Cc: stable@vger.kernel.org # v5.4
Suggested-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
Link: https://lore.kernel.org/r/20230509084746.48259-1-mirsad.todorovac@alu.unizg.hr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 6f67fbf819 ]
The `shift` variable which indicates the offset in the string at which
to start matching the pattern is initialized to `bm->patlen - 1`, but it
is not reset when a new block is retrieved. This means the implemen-
tation may start looking at later and later positions in each successive
block and miss occurrences of the pattern at the beginning. E.g.,
consider a HTTP packet held in a non-linear skb, where the HTTP request
line occurs in the second block:
[... 52 bytes of packet headers ...]
GET /bmtest HTTP/1.1\r\nHost: www.example.com\r\n\r\n
and the pattern is "GET /bmtest".
Once the first block comprising the packet headers has been examined,
`shift` will be pointing to somewhere near the end of the block, and so
when the second block is examined the request line at the beginning will
be missed.
Reinitialize the variable for each new block.
Fixes: 8082e4ed0a ("[LIB]: Boyer-Moore extension for textsearch infrastructure strike #2")
Link: https://bugzilla.netfilter.org/show_bug.cgi?id=1390
Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 4e0473f106 ]
When calling irq_set_affinity_notifier() with NULL at the notify
argument, it will cause freeing of the glue pointer in the
corresponding array entry but will leave the pointer in the array. A
subsequent call to free_irq_cpu_rmap() will try to free this entry again
leading to possible use after free.
Fix that by setting NULL to the array entry and checking that we have
non-zero at the array entry when iterating over the array in
free_irq_cpu_rmap().
The current code does not suffer from this since there are no cases
where irq_set_affinity_notifier(irq, NULL) (note the NULL passed for the
notify arg) is called, followed by a call to free_irq_cpu_rmap() so we
don't hit and issue. Subsequent patches in this series excersize this
flow, hence the required fix.
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Eli Cohen <elic@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 0af462f19e upstream.
The recent fix to ensure atomicity of lookup and allocation inadvertently
broke the pool refill mechanism.
Prior to that change debug_objects_activate() and debug_objecs_assert_init()
invoked debug_objecs_init() to set up the tracking object for statically
initialized objects. That's not longer the case and debug_objecs_init() is
now the only place which does pool refills.
Depending on the number of statically initialized objects this can be
enough to actually deplete the pool, which was observed by Ido via a
debugobjects OOM warning.
Restore the old behaviour by adding explicit refill opportunities to
debug_objects_activate() and debug_objecs_assert_init().
Fixes: 63a759694e ("debugobject: Prevent init race with static objects")
Reported-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Ido Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/r/871qk05a9d.ffs@tglx
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 63a759694e ]
Statically initialized objects are usually not initialized via the init()
function of the subsystem. They are special cased and the subsystem
provides a function to validate whether an object which is not yet tracked
by debugobjects is statically initialized. This means the object is started
to be tracked on first use, e.g. activation.
This works perfectly fine, unless there are two concurrent operations on
that object. Schspa decoded the problem:
T0 T1
debug_object_assert_init(addr)
lock_hash_bucket()
obj = lookup_object(addr);
if (!obj) {
unlock_hash_bucket();
- > preemption
lock_subsytem_object(addr);
activate_object(addr)
lock_hash_bucket();
obj = lookup_object(addr);
if (!obj) {
unlock_hash_bucket();
if (is_static_object(addr))
init_and_track(addr);
lock_hash_bucket();
obj = lookup_object(addr);
obj->state = ACTIVATED;
unlock_hash_bucket();
subsys function modifies content of addr,
so static object detection does
not longer work.
unlock_subsytem_object(addr);
if (is_static_object(addr)) <- Fails
debugobject emits a warning and invokes the fixup function which
reinitializes the already active object in the worst case.
This race exists forever, but was never observed until mod_timer() got a
debug_object_assert_init() added which is outside of the timer base lock
held section right at the beginning of the function to cover the lockless
early exit points too.
Rework the code so that the lookup, the static object check and the
tracking object association happens atomically under the hash bucket
lock. This prevents the issue completely as all callers are serialized on
the hash bucket lock and therefore cannot observe inconsistent state.
Fixes: 3ac7fe5a4a ("infrastructure to debug (dynamic) objects")
Reported-by: syzbot+5093ba19745994288b53@syzkaller.appspotmail.com
Debugged-by: Schspa Shi <schspa@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://syzkaller.appspot.com/bug?id=22c8a5938eab640d1c6bcc0e3dc7be519d878462
Link: https://lore.kernel.org/lkml/20230303161906.831686-1-schspa@gmail.com
Link: https://lore.kernel.org/r/87zg7dzgao.ffs@tglx
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7361d1bc30 ]
The helper mpi_read_raw_from_sgl sets the number of entries in
the SG list according to nbytes. However, if the last entry
in the SG list contains more data than nbytes, then it may overrun
the buffer because it only allocates enough memory for nbytes.
Fixes: 2d4d1eea54 ("lib/mpi: Add mpi sgl helpers")
Reported-by: Roberto Sassu <roberto.sassu@huaweicloud.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 74e19ef0ff upstream.
The results of "access_ok()" can be mis-speculated. The result is that
you can end speculatively:
if (access_ok(from, size))
// Right here
even for bad from/size combinations. On first glance, it would be ideal
to just add a speculation barrier to "access_ok()" so that its results
can never be mis-speculated.
But there are lots of system calls just doing access_ok() via
"copy_to_user()" and friends (example: fstat() and friends). Those are
generally not problematic because they do not _consume_ data from
userspace other than the pointer. They are also very quick and common
system calls that should not be needlessly slowed down.
"copy_from_user()" on the other hand uses a user-controller pointer and
is frequently followed up with code that might affect caches. Take
something like this:
if (!copy_from_user(&kernelvar, uptr, size))
do_something_with(kernelvar);
If userspace passes in an evil 'uptr' that *actually* points to a kernel
addresses, and then do_something_with() has cache (or other)
side-effects, it could allow userspace to infer kernel data values.
Add a barrier to the common copy_from_user() code to prevent
mis-speculated values which happen after the copy.
Also add a stub for architectures that do not define barrier_nospec().
This makes the macro usable in generic code.
Since the barrier is now usable in generic code, the x86 #ifdef in the
BPF code can also go away.
Reported-by: Jordy Zomer <jordyzomer@google.com>
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Daniel Borkmann <daniel@iogearbox.net> # BPF bits
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit f0950402e8 ]
Most netlink attributes are parsed and validated from
__nla_validate_parse() or validate_nla()
u16 type = nla_type(nla);
if (type == 0 || type > maxtype) {
/* error or continue */
}
@type is then used as an array index and can be used
as a Spectre v1 gadget.
array_index_nospec() can be used to prevent leaking
content of kernel memory to malicious users.
This should take care of vast majority of netlink uses,
but an audit is needed to take care of others where
validation is not yet centralized in core netlink functions.
Fixes: bfa83a9e03 ("[NETLINK]: Type-safe netlink messages/attributes interface")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20230119110150.2678537-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f5fe24ef17 ]
On the x86-64 architecture even a failing cmpxchg grants exclusive
access to the cacheline, making it preferable to retry the failed op
immediately instead of stalling with the pause instruction.
To illustrate the impact, below are benchmark results obtained by
running various will-it-scale tests on top of the 6.2-rc3 kernel and
Cascade Lake (2 sockets * 24 cores * 2 threads) CPU.
All results in ops/s. Note there is some variance in re-runs, but the
code is consistently faster when contention is present.
open3 ("Same file open/close"):
proc stock no-pause
1 805603 814942 (+%1)
2 1054980 1054781 (-0%)
8 1544802 1822858 (+18%)
24 1191064 2199665 (+84%)
48 851582 1469860 (+72%)
96 609481 1427170 (+134%)
fstat2 ("Same file fstat"):
proc stock no-pause
1 3013872 3047636 (+1%)
2 4284687 4400421 (+2%)
8 3257721 5530156 (+69%)
24 2239819 5466127 (+144%)
48 1701072 5256609 (+209%)
96 1269157 6649326 (+423%)
Additionally, a kernel with a private patch to help access() scalability:
access2 ("Same file access"):
proc stock patched patched
+nopause
24 2378041 2005501 5370335 (-15% / +125%)
That is, fixing the problems in access itself *reduces* scalability
after the cacheline ping-pong only happens in lockref with the pause
instruction.
Note that fstat and access benchmarks are not currently integrated into
will-it-scale, but interested parties can find them in pull requests to
said project.
Code at hand has a rather tortured history. First modification showed
up in commit d472d9d98b ("lockref: Relax in cmpxchg loop"), written
with Itanium in mind. Later it got patched up to use an arch-dependent
macro to stop doing it on s390 where it caused a significant regression.
Said macro had undergone revisions and was ultimately eliminated later,
going back to cpu_relax.
While I intended to only remove cpu_relax for x86-64, I got the
following comment from Linus:
I would actually prefer just removing it entirely and see if
somebody else hollers. You have the numbers to prove it hurts on
real hardware, and I don't think we have any numbers to the
contrary.
So I think it's better to trust the numbers and remove it as a
failure, than say "let's just remove it on x86-64 and leave
everybody else with the potentially broken code"
Additionally, Will Deacon (maintainer of the arm64 port, one of the
architectures previously benchmarked):
So, from the arm64 side of the fence, I'm perfectly happy just
removing the cpu_relax() calls from lockref.
As such, come back full circle in history and whack it altogether.
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://lore.kernel.org/all/CAGudoHHx0Nqg6DE70zAVA75eV-HXfWyhVMWZ-aSeOofkA_=WdA@mail.gmail.com/
Acked-by: Tony Luck <tony.luck@intel.com> # ia64
Acked-by: Nicholas Piggin <npiggin@gmail.com> # powerpc
Acked-by: Will Deacon <will@kernel.org> # arm64
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bb90d4bc7b ]
Working through a conversion to a call kmap_local_page() instead of
kmap() revealed many places where the pattern kmap/memcpy/kunmap
occurred.
Eric Biggers, Matthew Wilcox, Christoph Hellwig, Dan Williams, and Al
Viro all suggested putting this code into helper functions. Al Viro
further pointed out that these functions already existed in the iov_iter
code.[1]
Various locations for the lifted functions were considered.
Headers like mm.h or string.h seem ok but don't really portray the
functionality well. pagemap.h made some sense but is for page cache
functionality.[2]
Another alternative would be to create a new header for the promoted
memcpy functions, but it masks the fact that these are designed to copy
to/from pages using the kernel direct mappings and complicates matters
with a new header.
Placing these functions in 'highmem.h' is suboptimal especially with the
changes being proposed in the functionality of kmap. From a caller
perspective including/using 'highmem.h' implies that the functions
defined in that header are only required when highmem is in use which is
increasingly not the case with modern processors. However, highmem.h is
where all the current functions like this reside (zero_user(),
clear_highpage(), clear_user_highpage(), copy_user_highpage(), and
copy_highpage()). So it makes the most sense even though it is
distasteful for some.[3]
Lift memcpy_to_page() and memcpy_from_page() to pagemap.h.
[1] https://lore.kernel.org/lkml/20201013200149.GI3576660@ZenIV.linux.org.uk/https://lore.kernel.org/lkml/20201013112544.GA5249@infradead.org/
[2] https://lore.kernel.org/lkml/20201208122316.GH7338@casper.infradead.org/
[3] https://lore.kernel.org/lkml/20201013200149.GI3576660@ZenIV.linux.org.uk/#thttps://lore.kernel.org/lkml/20201208163814.GN1563847@iweiny-DESK2.sc.intel.com/
Cc: Boris Pismenny <borisp@mellanox.com>
Cc: Or Gerlitz <gerlitz.or@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Suggested-by: Dan Williams <dan.j.williams@intel.com>
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Suggested-by: Eric Biggers <ebiggers@kernel.org>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: 956510c0c7 ("fs: ext4: initialize fsdata in pagecache_write()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
