KMSAN reported uninitialized data being written to disk when dumping
core. As a result, several kilobytes of kmalloc memory may be written
to the core file and then read by a non-privileged user.
Reported-by: sam <sunhaoyl@outlook.com> Signed-off-by: Alexander Potapenko <glider@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Kees Cook <keescook@chromium.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Alexey Dobriyan <adobriyan@gmail.com> Link: http://lkml.kernel.org/r/20200419100848.63472-1-glider@google.com Link: https://github.com/google/kmsan/issues/76 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
It turns out that RDRAND is pretty slow. Comparing these two
constructions:
for (i = 0; i < CHACHA_BLOCK_SIZE; i += sizeof(ret))
arch_get_random_long(&ret);
and
long buf[CHACHA_BLOCK_SIZE / sizeof(long)];
extract_crng((u8 *)buf);
it amortizes out to 352 cycles per long for the top one and 107 cycles
per long for the bottom one, on Coffee Lake Refresh, Intel Core i9-9880H.
And importantly, the top one has the drawback of not benefiting from the
real rng, whereas the bottom one has all the nice benefits of using our
own chacha rng. As get_random_u{32,64} gets used in more places (perhaps
beyond what it was originally intended for when it was introduced as
get_random_{int,long} back in the md5 monstrosity era), it seems like it
might be a good thing to strengthen its posture a tiny bit. Doing this
should only be stronger and not any weaker because that pool is already
initialized with a bunch of rdrand data (when available). This way, we
get the benefits of the hardware rng as well as our own rng.
Another benefit of this is that we no longer hit pitfalls of the recent
stream of AMD bugs in RDRAND. One often used code pattern for various
things is:
do {
val = get_random_u32();
} while (hash_table_contains_key(val));
That recent AMD bug rendered that pattern useless, whereas we're really
very certain that chacha20 output will give pretty distributed numbers,
no matter what.
So, this simplification seems better both from a security perspective
and from a performance perspective.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20200221201037.30231-1-Jason@zx2c4.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.16: Only get_random_int() exists here] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
SRBDS is an MDS-like speculative side channel that can leak bits from the
random number generator (RNG) across cores and threads. New microcode
serializes the processor access during the execution of RDRAND and
RDSEED. This ensures that the shared buffer is overwritten before it is
released for reuse.
While it is present on all affected CPU models, the microcode mitigation
is not needed on models that enumerate ARCH_CAPABILITIES[MDS_NO] in the
cases where TSX is not supported or has been disabled with TSX_CTRL.
The mitigation is activated by default on affected processors and it
increases latency for RDRAND and RDSEED instructions. Among other
effects this will reduce throughput from /dev/urandom.
* Enable administrator to configure the mitigation off when desired using
either mitigations=off or srbds=off.
* Export vulnerability status via sysfs
* Rename file-scoped macros to apply for non-whitelist table initializations.
[ bp: Massage,
- s/VULNBL_INTEL_STEPPING/VULNBL_INTEL_STEPPINGS/g,
- do not read arch cap MSR a second time in tsx_fused_off() - just pass it in,
- flip check in cpu_set_bug_bits() to save an indentation level,
- reflow comments.
jpoimboe: s/Mitigated/Mitigation/ in user-visible strings
tglx: Dropped the fused off magic for now
]
Signed-off-by: Mark Gross <mgross@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Neelima Krishnan <neelima.krishnan@intel.com>
[bwh: Backported to 3.16:
- CPU feature words and bugs are numbered differently
- Adjust filename for <asm/msr-index.h>] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Intel uses the same family/model for several CPUs. Sometimes the
stepping must be checked to tell them apart.
On x86 there can be at most 16 steppings. Add a steppings bitmask to
x86_cpu_id and a X86_MATCH_VENDOR_FAMILY_MODEL_STEPPING_FEATURE macro
and support for matching against family/model/stepping.
[ bp: Massage.
tglx: Lightweight variant for backporting ]
Signed-off-by: Mark Gross <mgross@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When journal size is set too big by "mkfs.ext4 -J size=", or when
we mount a crafted image to make journal inode->i_size too big,
the loop, "while (i < num)", holds cpu too long. This could cause
soft lockup.
Link: https://lore.kernel.org/r/20200211011752.29242-1-luoshijie1@huawei.com Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Shijie Luo <luoshijie1@huawei.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Since the journal inode is already checked when we added it to the
block validity's system zone, if we check it again, we'll just trigger
a failure.
This was causing failures like this:
[ 53.897001] EXT4-fs error (device sda): ext4_find_extent:909: inode
#8: comm jbd2/sda-8: pblk 121667583 bad header/extent: invalid extent entries - magic f30a, entries 8, max 340(340), depth 0(0)
[ 53.931430] jbd2_journal_bmap: journal block not found at offset 49 on sda-8
[ 53.938480] Aborting journal on device sda-8.
... but only if the system was under enough memory pressure that
logical->physical mapping for the journal inode gets pushed out of the
extent cache. (This is why it wasn't noticed earlier.)
Fixes: 345c0dbf3a30 ("ext4: protect journal inode's blocks using block_validity") Reported-by: Dan Rue <dan.rue@linaro.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
[bwh: Backported to 3.16: Use EXT4_HAS_COMPAT_FEATURE()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Commit 345c0dbf3a30 ("ext4: protect journal inode's blocks using
block_validity") failed to add an exception for the journal inode in
ext4_check_blockref(), which is the function used by ext4_get_branch()
for indirect blocks. This caused attempts to read from the ext3-style
journals to fail with:
There are two cases where u32 variables n and err are being checked
for less than zero error values, the checks is always false because
the variables are not signed. Fix this by making the variables ints.
Addresses-Coverity: ("Unsigned compared against 0") Fixes: 345c0dbf3a30 ("ext4: protect journal inode's blocks using block_validity") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Add the blocks which belong to the journal inode to block_validity's
system zone so attempts to deallocate or overwrite the journal due a
corrupted file system where the journal blocks are also claimed by
another inode.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202879 Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
[bwh: Backported to 3.16:
- Use EXT4_HAS_COMPAT_FEATURE()
- Use EIO instead of EFSCORRUPTED] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Tahsin Erdogan [Thu, 17 May 2018 16:23:04 +0000 (18:23 +0200)]
ext4: Make checks for metadata_csum feature safer
This is just a small part of commit dec214d00e0d7 "ext4: xattr inode
deduplication" that makes checks for metadata_csum feature safer and is
actually needed by following fixes.
Signed-off-by: Tahsin Erdogan <tahsin@google.com> Acked-by: Jan Kara <jack@suse.cz>
[bwh: Ported to 3.16: Use EXT4_HAS_RO_COMPAT_FEATURE()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This bug occurs when a size variable used for a buffer
is misused to access its strcpy-ed buffer.
Given a buffer along with its size variable (taken from user input),
from which, a new buffer is created using kstrdup().
Due to the original buffer containing 0 value in the middle,
the size of the kstrdup-ed buffer becomes smaller than that of the original.
So accessing the kstrdup-ed buffer with the same size variable
triggers memory access violation.
The fix makes sure no zero value in the buffer,
by comparing the strlen() of the orignal buffer with the size variable,
so that the access to the kstrdup-ed buffer is safe.
BUG: KASAN: slab-out-of-bounds in gadget_dev_desc_UDC_store+0x1ba/0x200
drivers/usb/gadget/configfs.c:266
Read of size 1 at addr ffff88806a55dd7e by task syz-executor.0/17208
Replace the 32bit exec_id with a 64bit exec_id to make it impossible
to wrap the exec_id counter. With care an attacker can cause exec_id
wrap and send arbitrary signals to a newly exec'd parent. This
bypasses the signal sending checks if the parent changes their
credentials during exec.
The severity of this problem can been seen that in my limited testing
of a 32bit exec_id it can take as little as 19s to exec 65536 times.
Which means that it can take as little as 14 days to wrap a 32bit
exec_id. Adam Zabrocki has succeeded wrapping the self_exe_id in 7
days. Even my slower timing is in the uptime of a typical server.
Which means self_exec_id is simply a speed bump today, and if exec
gets noticably faster self_exec_id won't even be a speed bump.
Extending self_exec_id to 64bits introduces a problem on 32bit
architectures where reading self_exec_id is no longer atomic and can
take two read instructions. Which means that is is possible to hit
a window where the read value of exec_id does not match the written
value. So with very lucky timing after this change this still
remains expoiltable.
I have updated the update of exec_id on exec to use WRITE_ONCE
and the read of exec_id in do_notify_parent to use READ_ONCE
to make it clear that there is no locking between these two
locations.
Link: https://lore.kernel.org/kernel-hardening/20200324215049.GA3710@pi3.com.pl Fixes: 2.3.23pre2 Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
[bwh: Backported to 3.16:
- Use ACCESS_ONCE()
- Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If the dxfer_len is greater than 256M then the request is invalid and we
need to call sg_remove_request in sg_common_write.
Link: https://lore.kernel.org/r/1586777361-17339-1-git-send-email-huawei.libin@huawei.com Fixes: f930c7043663 ("scsi: sg: only check for dxfer_len greater than 256M") Acked-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Li Bin <huawei.libin@huawei.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fix a minor memory leak when there is an error opening a /dev/sg device.
Fixes: cc833acbee9d ("sg: O_EXCL and other lock handling") Cc: <stable@vger.kernel.org> Reviewed-by: Ewan D. Milne <emilne@redhat.com> Signed-off-by: Tony Battersby <tonyb@cybernetics.com> Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If the list search in sg_get_rq_mark() fails to find a valid request, we
return a bogus element. This then can later lead to a GPF in
sg_remove_scat().
So don't return bogus Sg_requests in sg_get_rq_mark() but NULL in case
the list search doesn't find a valid request.
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Reported-by: Andrey Konovalov <andreyknvl@google.com> Cc: Hannes Reinecke <hare@suse.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Doug Gilbert <dgilbert@interlog.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Doug Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Cc: Tony Battersby <tonyb@cybernetics.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Don't make any assumptions on the sg_io_hdr_t::dxfer_direction or the
sg_io_hdr_t::dxferp in order to determine if it is a valid request. The
only way we can check for bad requests is by checking if the length
exceeds 256M.
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Fixes: 28676d869bbb (scsi: sg: check for valid direction before starting the request) Reported-by: Jason L Tibbitts III <tibbs@math.uh.edu> Tested-by: Jason L Tibbitts III <tibbs@math.uh.edu> Suggested-by: Doug Gilbert <dgilbert@interlog.com> Cc: Doug Gilbert <dgilbert@interlog.com> Cc: <stable@vger.kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.16: Include <linux/sizes.h>] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
dxfer_len is an unsigned int and we always assign a value > 0 to it, so
it doesn't make any sense to check if it is < 0. We can't really check
dxferp as well as we have both NULL and not NULL cases in the possible
call paths.
So just return true for SG_DXFER_FROM_DEV transfer in
sg_is_valid_dxfer().
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Reported-by: Colin Ian King <colin.king@canonical.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
SG_DXFER_FROM_DEV transfers do not necessarily have a dxferp as we set
it to NULL for the old sg_io read/write interface, but must have a
length bigger than 0. This fixes a regression introduced by commit 28676d869bbb ("scsi: sg: check for valid direction before starting the
request")
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Fixes: 28676d869bbb ("scsi: sg: check for valid direction before starting the request") Reported-by: Chris Clayton <chris2553@googlemail.com> Tested-by: Chris Clayton <chris2553@googlemail.com> Cc: Douglas Gilbert <dgilbert@interlog.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Chris Clayton <chris2553@googlemail.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Cc: Cristian Crinteanu <crinteanu.cristian@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
sg_remove_sfp_usercontext() is clearing any sg requests, but needs to
take 'rq_list_lock' when modifying the list.
Reported-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Tested-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The ioctl SET_FORCE_LOW_DMA has never worked since the initial git
check-in, and the respective setting is nowadays handled correctly. So
disable it entirely.
Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Tested-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Commit 109bade9c625 ("scsi: sg: use standard lists for sg_requests")
introduced an off-by-one error in sg_ioctl(), which was fixed by commit bd46fc406b30 ("scsi: sg: off by one in sg_ioctl()").
Unfortunately commit 4759df905a47 ("scsi: sg: factor out
sg_fill_request_table()") moved that code, and reintroduced the
bug (perhaps due to a botched rebase). Fix it again.
Fixes: 4759df905a47 ("scsi: sg: factor out sg_fill_request_table()") Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When calling SG_GET_REQUEST_TABLE ioctl only a half-filled table is
returned; the remaining part will then contain stale kernel memory
information. This patch zeroes out the entire table to avoid this
issue.
Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Factor out sg_fill_request_table() for better readability.
[mkp: typos, applied by hand]
Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If "val" is SG_MAX_QUEUE then we are one element beyond the end of the
"rinfo" array so the > should be >=.
Fixes: 109bade9c625 ("scsi: sg: use standard lists for sg_requests") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
'Sg_request' is using a private list implementation; convert it to
standard lists.
Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Tested-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Tested-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Commit 1bc0eb044615 ("scsi: sg: protect accesses to 'reserved' page
array") adds needed concurrency protection for the "reserve" buffer.
Some checks that are initially made outside the lock are replicated once
the lock is taken to ensure the checks and resulting decisions are made
using consistent state.
The check that a request with flag SG_FLAG_MMAP_IO set fits in the
reserve buffer also needs to be performed again under the lock to ensure
the reserve buffer length compared against matches the value in effect
when the request is linked to the reserve buffer. An -ENOMEM should be
returned in this case, instead of switching over to an indirect buffer
as for non-MMAP_IO requests.
Signed-off-by: Todd Poynor <toddpoynor@google.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Take f_mutex around mmap() processing to protect against races with the
SG_SET_RESERVED_SIZE ioctl. Ensure the reserve buffer length remains
consistent during the mapping operation, and set the "mmap called" flag
to prevent further changes to the reserved buffer size as an atomic
operation with the mapping.
[mkp: fixed whitespace]
Signed-off-by: Todd Poynor <toddpoynor@google.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Once the reserved page array is unused we can reset the 'res_in_use'
state; here we can do a lazy update without holding the mutex as we only
need to check against concurrent access, not concurrent release.
[mkp: checkpatch]
Fixes: 1bc0eb044615 ("scsi: sg: protect accesses to 'reserved' page array") Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Cc: Todd Poynor <toddpoynor@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The 'reserved' page array is used as a short-cut for mapping data,
saving us to allocate pages per request. However, the 'reserved' array
is only capable of holding one request, so this patch introduces a mutex
for protect 'sg_fd' against concurrent accesses.
Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Tested-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[toddpoynor@google.com: backport to 3.18-4.9, fixup for bad ioctl
SG_SET_FORCE_LOW_DMA code removed in later versions and not modified by
the original patch.]
Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Tested-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Todd Poynor <toddpoynor@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Ben Hutchings [Thu, 28 May 2020 17:54:25 +0000 (18:54 +0100)]
scsi: sg: Change next_cmd_len handling to mirror upstream
Change the type of next_cmd_len to unsigned char, done in upstream
commit 65c26a0f3969 "sg: relax 16 byte cdb restriction".
Move the range check from sg_write() to sg_ioctl(), which was done by
that commit and commit bf33f87dd04c "scsi: sg: check length passed to
SG_NEXT_CMD_LEN". Continue limiting the command length to
MAX_COMMAND_SIZE (16).
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This prevents integer overflow when converting the request queue's
max_sectors from sectors to bytes. However, this is a preparation for
extending the data type of max_sectors in struct Scsi_Host and
scsi_host_template. So, it is impossible to happen this integer
overflow for now, because SCSI low-level drivers can not specify
max_sectors greater than 0xffff due to the data type limitation.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This addresses a problem reported by Vaughan Cao concerning
the correctness of the O_EXCL logic in the sg driver. POSIX
doesn't defined O_EXCL semantics on devices but "allow only
one open file descriptor at a time per sg device" is a rough
definition. The sg driver's semantics have been to wait
on an open() when O_NONBLOCK is not given and there are
O_EXCL headwinds. Nasty things can happen during that wait
such as the device being detached (removed). So multiple
locks are reworked in this patch making it large and hard
to break down into digestible bits.
This patch is against Linus's current git repository which
doesn't include any sg patches sent in the last few weeks.
Hence this patch touches as little as possible that it
doesn't need to and strips out most SCSI_LOG_TIMEOUT()
changes in v3 because Hannes said he was going to rework all
that stuff.
The sg3_utils package has several test programs written to
test this patch. See examples/sg_tst_excl*.cpp .
Not all the locks and flags in sg have been re-worked in
this patch, notably sg_request::done . That can wait for
a follow-up patch if this one meets with approval.
Signed-off-by: Douglas Gilbert <dgilbert@interlog.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
mwifiex_ret_wmm_get_status() calls memcpy() without checking the
destination size.Since the source is given from remote AP which
contains illegal wmm elements , this may trigger a heap buffer
overflow.
Fix it by putting the length check before calling memcpy().
Signed-off-by: Qing Xu <m1s5p6688@gmail.com> Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
[bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
mwifiex_cmd_append_vsie_tlv() calls memcpy() without checking
the destination size may trigger a buffer overflower,
which a local user could use to cause denial of service
or the execution of arbitrary code.
Fix it by putting the length check before calling memcpy().
Signed-off-by: Qing Xu <m1s5p6688@gmail.com> Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
[bwh: Backported to 3.16:
- Use dev_info() instead of mwifiex_dbg()
- Adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Tom Hatskevich reported that we look up "iocp" then, in the called
functions we do a second copy_from_user() and look it up again.
The problem that could cause is:
drivers/message/fusion/mptctl.c
674 /* All of these commands require an interrupt or
675 * are unknown/illegal.
676 */
677 if ((ret = mptctl_syscall_down(iocp, nonblock)) != 0)
^^^^
We take this lock.
678 return ret;
679
680 if (cmd == MPTFWDOWNLOAD)
681 ret = mptctl_fw_download(arg);
^^^
Then the user memory changes and we look up "iocp" again but a different
one so now we are holding the incorrect lock and have a race condition.
682 else if (cmd == MPTCOMMAND)
683 ret = mptctl_mpt_command(arg);
The security impact of this bug is not as bad as it could have been
because these operations are all privileged and root already has
enormous destructive power. But it's still worth fixing.
This patch passes the "iocp" pointer to the functions to avoid the
second lookup. That deletes 100 lines of code from the driver so
it's a nice clean up as well.
Link: https://lore.kernel.org/r/20200114123414.GA7957@kadam Reported-by: Tom Hatskevich <tom2001tom.23@gmail.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
It's true that we probably should have a bounds check here.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
FuzzUSB (a variant of syzkaller) found a free-while-still-in-use bug
in the USB scatter-gather library:
BUG: KASAN: use-after-free in atomic_read
include/asm-generic/atomic-instrumented.h:26 [inline]
BUG: KASAN: use-after-free in usb_hcd_unlink_urb+0x5f/0x170
drivers/usb/core/hcd.c:1607
Read of size 4 at addr ffff888065379610 by task kworker/u4:1/27
This bug occurs when cancellation of the S-G transfer races with
transfer completion. When that happens, usb_sg_cancel() may continue
to access the transfer's URBs after usb_sg_wait() has freed them.
The bug is caused by the fact that usb_sg_cancel() does not take any
sort of reference to the transfer, and so there is nothing to prevent
the URBs from being deallocated while the routine is trying to use
them. The fix is to take such a reference by incrementing the
transfer's io->count field while the cancellation is in progres and
decrementing it afterward. The transfer's URBs are not deallocated
until io->complete is triggered, which happens when io->count reaches
zero.
usb_submit_urb() may take quite long to execute. For example, a
single sg list may have 30 or more entries, possibly leading to that
many calls to DMA-map pages. This can cause interrupt latency of
several hundred micro-seconds.
Avoid the problem by releasing the io->lock spinlock and re-enabling
interrupts before calling usb_submit_urb(). This opens races with
usb_sg_cancel() and sg_complete(). Handle those races by using
usb_block_urb() to stop URBs from being submitted after
usb_sg_cancel() or sg_complete() with error.
Note that usb_unlink_urb() is guaranteed to return -ENODEV if
!io->urbs[i]->dev and since the -ENODEV case is already handled,
we don't have to check for !io->urbs[i]->dev explicitly.
Before this change, reading 512MB from an ext3 filesystem on a USB
memory stick showed a throughput of 12 MB/s with about 500 missed
deadlines.
With this change, reading the same file gave the same throughput but
only one or two missed deadlines.
Signed-off-by: David Mosberger <davidm@egauge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fix the SELinux netlink_send hook to properly handle multiple netlink
messages in a single sk_buff; each message is parsed and subject to
SELinux access control. Prior to this patch, SELinux only inspected
the first message in the sk_buff.
Cc: stable@vger.kernel.org Reported-by: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: Stephen Smalley <stephen.smalley.work@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Any process is able to send netlink messages with invalid types.
Make the warning rate-limited to prevent too much log spam.
The warning is supposed to help to find misbehaving programs, so
print the triggering command name and pid.
Reported-by: Florian Weimer <fweimer@redhat.com> Signed-off-by: Vladis Dronov <vdronov@redhat.com>
[PM: subject line tweak to make checkpatch.pl happy] Signed-off-by: Paul Moore <pmoore@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This prints the 'sclass' field as string instead of index in unrecognized netlink message.
The textual representation makes it easier to distinguish the right class.
Signed-off-by: Marek Milkovic <mmilkovi@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: 80-char width fixes] Signed-off-by: Paul Moore <pmoore@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Convert WARN_ONCE() to printk() in selinux_nlmsg_perm().
After conversion from audit_log() in commit e173fb26, WARN_ONCE() was
deemed too alarmist, so switch it to printk().
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: Changed to printk(WARNING) so we catch all of the different
invalid netlink messages. In Richard's defense, he brought this
point up earlier, but I didn't understand his point at the time.] Signed-off-by: Paul Moore <pmoore@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Rename "type=" to nlmsg_type=" to avoid confusion with the audit record
type.
Added "protocol=" to help track down which protocol (NETLINK_AUDIT?) was used
within the netlink protocol family.
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[Rewrote the patch subject line] Signed-off-by: Paul Moore <pmoore@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Dev_hold has to be called always in netdev_queue_add_kobject.
Otherwise usage count drops below 0 in case of failure in
kobject_init_and_add.
Fixes: b8eb718348b8 ("net-sysfs: Fix reference count leak in rx|netdev_queue_add_kobject") Reported-by: Hulk Robot <hulkci@huawei.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: David Miller <davem@davemloft.net> Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
kobject_put() should only be called in error path.
Fixes: b8eb718348b8 ("net-sysfs: Fix reference count leak in rx|netdev_queue_add_kobject") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jouni Hogander <jouni.hogander@unikie.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
kobject_init_and_add takes reference even when it fails. This has
to be given up by the caller in error handling. Otherwise memory
allocated by kobject_init_and_add is never freed. Originally found
by Syzkaller:
Cc: David Miller <davem@davemloft.net> Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com> Signed-off-by: Jouni Hogander <jouni.hogander@unikie.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
As the description before netdev_run_todo, we cannot call free_netdev
before rtnl_unlock, fix it by reorder the code.
Signed-off-by: yangerkun <yangerkun@huawei.com> Reviewed-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Slip_open doesn't clean-up device which registration failed from the
slip_devs device list. On next open after failure this list is iterated
and freed device is accessed. Fix this by calling sl_free_netdev in error
path.
Fixes: 3b5a39979daf ("slip: Fix memory leak in slip_open error path") Reported-by: syzbot+4d5170758f3762109542@syzkaller.appspotmail.com Cc: David Miller <davem@davemloft.net> Cc: Oliver Hartkopp <socketcan@hartkopp.net> Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com> Signed-off-by: Jouni Hogander <jouni.hogander@unikie.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: sl_free_netdev() calls free_netdev() here, so
delete the direct call to free_netdev()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Driver/net/can/slcan.c is derived from slip.c. Memory leak was detected
by Syzkaller in slcan. Same issue exists in slip.c and this patch is
addressing the leak in slip.c.
Here is the slcan memory leak trace reported by Syzkaller:
Cc: "David S. Miller" <davem@davemloft.net> Cc: Oliver Hartkopp <socketcan@hartkopp.net> Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com> Signed-off-by: Jouni Hogander <jouni.hogander@unikie.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
As the description before netdev_run_todo, we cannot call free_netdev
before rtnl_unlock, fix it by reorder the code.
This patch is a 1:1 copy of upstream slip.c commit f596c87005f7
("slip: not call free_netdev before rtnl_unlock in slip_open").
Reported-by: yangerkun <yangerkun@huawei.com> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Slcan_open doesn't clean-up device which registration failed from the
slcan_devs device list. On next open this list is iterated and freed
device is accessed. Fix this by calling slc_free_netdev in error path.
Driver/net/can/slcan.c is derived from slip.c. Use-after-free error was
identified in slip_open by syzboz. Same bug is in slcan.c. Here is the
trace from the Syzbot slip report:
Fixes: ed50e1600b44 ("slcan: Fix memory leak in error path") Cc: Wolfgang Grandegger <wg@grandegger.com> Cc: Marc Kleine-Budde <mkl@pengutronix.de> Cc: David Miller <davem@davemloft.net> Cc: Oliver Hartkopp <socketcan@hartkopp.net> Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com> Signed-off-by: Jouni Hogander <jouni.hogander@unikie.com> Acked-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
[bwh: Backported to 3.16: slc_free_netdev() calls free_netdev() here, so
delete the direct call to free_netdev()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When upcalling gssproxy, cache_head.expiry_time is set as a
timeval, not seconds since boot. As such, RPC cache expiry
logic will not clean expired objects created under
auth.rpcsec.context cache.
This has proven to cause kernel memory leaks on field. Using
64 bit variants of getboottime/timespec
Expiration times have worked this way since 2010's c5b29f885afe "sunrpc:
use seconds since boot in expiry cache". The gssproxy code introduced
in 2012 added gss_proxy_save_rsc and introduced the bug. That's a while
for this to lurk, but it required a bit of an extreme case to make it
obvious.
Signed-off-by: Roberto Bergantinos Corpas <rbergant@redhat.com> Fixes: 030d794bf498 "SUNRPC: Use gssproxy upcall for server..." Tested-By: Frank Sorenson <sorenson@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
[bwh: Backported to 3.16: Use struct timespec and getboottime()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
syzbot managed to send an IPX packet through bond_alb_xmit()
and af_packet and triggered a use-after-free.
First, bond_alb_xmit() was using ipx_hdr() helper to reach
the IPX header, but ipx_hdr() was using the transport offset
instead of the network offset. In the particular syzbot
report transport offset was 0xFFFF
This patch removes ipx_hdr() since it was only (mis)used from bonding.
Then we need to make sure IPv4/IPv6/IPX headers are pulled
in skb->head before dereferencing anything.
BUG: KASAN: use-after-free in bond_alb_xmit+0x153a/0x1590 drivers/net/bonding/bond_alb.c:1452
Read of size 2 at addr ffff8801ce56dfff by task syz-executor.2/18108
(if (ipx_hdr(skb)->ipx_checksum != IPX_NO_CHECKSUM) ...)
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Jay Vosburgh <j.vosburgh@gmail.com> Cc: Veaceslav Falico <vfalico@gmail.com> Cc: Andy Gospodarek <andy@greyhouse.net> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16:
- Don't delete ipx_hdr() as it's still used by net/ipx here
- Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If we have a soft mount we should fail commands for session-setup
failures (such as the password having changed/ account being deleted/ ...)
and return an error back to the application.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When a NFS directory page cache page is removed from the page cache,
its contents are freed through a call to nfs_readdir_clear_array().
To prevent the removal of the page cache entry until after we've
finished reading it, we must take the page lock.
Fixes: 11de3b11e08c ("NFS: Fix a memory leak in nfs_readdir") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Reviewed-by: Benjamin Coddington <bcodding@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
nfs_readdir_xdr_to_array() must not exit without having initialised
the array, so that the page cache deletion routines can safely
call nfs_readdir_clear_array().
Furthermore, we should ensure that if we exit nfs_readdir_filler()
with an error, we free up any page contents to prevent a leak
if we try to fill the page again.
Fixes: 11de3b11e08c ("NFS: Fix a memory leak in nfs_readdir") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Reviewed-by: Benjamin Coddington <bcodding@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Running randconfig on arm64 using KCONFIG_SEED=0x40C5E904 (e.g. on v5.5)
produces the .config with CONFIG_EFI=y and CONFIG_CPU_BIG_ENDIAN=y,
which does not meet the !CONFIG_CPU_BIG_ENDIAN dependency.
This is because the user choice for CONFIG_CPU_LITTLE_ENDIAN vs
CONFIG_CPU_BIG_ENDIAN is set by randomize_choice_values() after the
value of CONFIG_EFI is calculated.
When this happens, the has_changed flag should be set.
Currently, it takes the result from the last iteration. It should
accumulate all the results of the loop.
Fixes: 3b9a19e08960 ("kconfig: loop as long as we changed some symbols in randconfig") Reported-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fixes: 6fa8c0144b77 ("[NET_SCHED]: Use nla_policy for attribute validation in classifiers") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
kernel BUG at kernel/time/timer.c:1154!
BUG_ON(timer_pending(timer) || !timer->function) in add_timer_on().
At the same time another cpu got:
general protection fault: 0000 [#1] SMP PTI of poinson pointer 0xdead000000000200 in:
__hlist_del at include/linux/list.h:681
(inlined by) detach_timer at kernel/time/timer.c:818
(inlined by) expire_timers at kernel/time/timer.c:1355
(inlined by) __run_timers at kernel/time/timer.c:1686
(inlined by) run_timer_softirq at kernel/time/timer.c:1699
Unfortunately kernel logs are badly scrambled, stacktraces are lost.
Printing the timer->function before the BUG_ON() pointed to
clocksource_watchdog().
The execution of clocksource_watchdog() can race with a sequence of
clocksource_stop_watchdog() .. clocksource_start_watchdog():
total_retrans needs to be cleared in tcp_disconnect().
tcp_disconnect() is rarely used, but it is worth fixing it.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: SeongJae Park <sjpark@amazon.de> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
After DMA is complete, and the device and CPU caches are synchronized,
it's still required to mark the CPU pages as dirty, if the data was
coming from the device. However, this driver was just issuing a bare
put_page() call, without any set_page_dirty*() call.
Fix the problem, by calling set_page_dirty_lock() if the CPU pages were
potentially receiving data from the device.
Link: http://lkml.kernel.org/r/20200107224558.2362728-11-jhubbard@nvidia.com Signed-off-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Björn Töpel <bjorn.topel@intel.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jan Kara <jack@suse.cz> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Leon Romanovsky <leonro@mellanox.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
What we are trying to do is change the '=' character to a NUL terminator
and then at the end of the function we restore it back to an '='. The
problem is there are two error paths where we jump to the end of the
function before we have replaced the '=' with NUL.
We end up putting the '=' in the wrong place (possibly one element
before the start of the buffer).
Link: http://lkml.kernel.org/r/20200115055426.vdjwvry44nfug7yy@kili.mountain Reported-by: syzbot+e64a13c5369a194d67df@syzkaller.appspotmail.com Fixes: 095f1fc4ebf3 ("mempolicy: rework shmem mpol parsing and display") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Vlastimil Babka <vbabka@suse.cz>
Dmitry Vyukov <dvyukov@google.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
There is a race between adding and removing elements to the tree mod log
list and rbtree that can lead to use-after-free problems.
Consider the following example that explains how/why the problems happens:
1) Task A has mod log element with sequence number 200. It currently is
the only element in the mod log list;
2) Task A calls btrfs_put_tree_mod_seq() because it no longer needs to
access the tree mod log. When it enters the function, it initializes
'min_seq' to (u64)-1. Then it acquires the lock 'tree_mod_seq_lock'
before checking if there are other elements in the mod seq list.
Since the list it empty, 'min_seq' remains set to (u64)-1. Then it
unlocks the lock 'tree_mod_seq_lock';
3) Before task A acquires the lock 'tree_mod_log_lock', task B adds
itself to the mod seq list through btrfs_get_tree_mod_seq() and gets a
sequence number of 201;
4) Some other task, name it task C, modifies a btree and because there
elements in the mod seq list, it adds a tree mod elem to the tree
mod log rbtree. That node added to the mod log rbtree is assigned
a sequence number of 202;
5) Task B, which is doing fiemap and resolving indirect back references,
calls btrfs get_old_root(), with 'time_seq' == 201, which in turn
calls tree_mod_log_search() - the search returns the mod log node
from the rbtree with sequence number 202, created by task C;
6) Task A now acquires the lock 'tree_mod_log_lock', starts iterating
the mod log rbtree and finds the node with sequence number 202. Since
202 is less than the previously computed 'min_seq', (u64)-1, it
removes the node and frees it;
7) Task B still has a pointer to the node with sequence number 202, and
it dereferences the pointer itself and through the call to
__tree_mod_log_rewind(), resulting in a use-after-free problem.
This issue can be triggered sporadically with the test case generic/561
from fstests, and it happens more frequently with a higher number of
duperemove processes. When it happens to me, it either freezes the VM or
it produces a trace like the following before crashing:
Fix this by ensuring that btrfs_put_tree_mod_seq() computes the minimum
sequence number and iterates the rbtree while holding the lock
'tree_mod_log_lock' in write mode. Also get rid of the 'tree_mod_seq_lock'
lock, since it is now redundant.
Fixes: bd989ba359f2ac ("Btrfs: add tree modification log functions") Fixes: 097b8a7c9e48e2 ("Btrfs: join tree mod log code with the code holding back delayed refs") Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
[bwh: Backported to 3.16:
- Use tree_mod_log_write_{,un}lock() in ctree.c for consistency
- Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
There's an OF helper called of_dma_is_coherent(), which checks if a
device has a "dma-coherent" property to see if the device is coherent
for DMA.
But on some platforms devices are coherent by default, and on some
platforms it's not possible to update existing device trees to add the
"dma-coherent" property.
So add a Kconfig symbol to allow arch code to tell
of_dma_is_coherent() that devices are coherent by default, regardless
of the presence of the property.
Select that symbol on powerpc when NOT_COHERENT_CACHE is not set, ie.
when the system has a coherent cache.
Fixes: 92ea637edea3 ("of: introduce of_dma_is_coherent() helper") Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rob Herring <robh@kernel.org>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When reading/writing using the guest/host cache, check for a bad hva
before checking for a NULL memslot, which triggers the slow path for
handing cross-page accesses. Because the memslot is nullified on error
by __kvm_gfn_to_hva_cache_init(), if the bad hva is encountered after
crossing into a new page, then the kvm_{read,write}_guest() slow path
could potentially write/access the first chunk prior to detecting the
bad hva.
Arguably, performing a partial access is semantically correct from an
architectural perspective, but that behavior is certainly not intended.
In the original implementation, memslot was not explicitly nullified
and therefore the partial access behavior varied based on whether the
memslot itself was null, or if the hva was simply bad. The current
behavior was introduced as a seemingly unintentional side effect in
commit f1b9dd5eb86c ("kvm: Disallow wraparound in
kvm_gfn_to_hva_cache_init"), which justified the change with "since some
callers don't check the return code from this function, it sit seems
prudent to clear ghc->memslot in the event of an error".
Regardless of intent, the partial access is dependent on _not_ checking
the result of the cache initialization, which is arguably a bug in its
own right, at best simply weird.
Fixes: 8f964525a121 ("KVM: Allow cross page reads and writes from cached translations.") Cc: Jim Mattson <jmattson@google.com> Cc: Andrew Honig <ahonig@google.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This fixes a Spectre-v1/L1TF vulnerability in __kvm_set_dr() and
kvm_get_dr().
Both kvm_get_dr() and kvm_set_dr() (a wrapper of __kvm_set_dr()) are
exported symbols so KVM should tream them conservatively from a security
perspective.
Fixes: 020df0794f57 ("KVM: move DR register access handling into generic code") Signed-off-by: Nick Finco <nifi@google.com> Signed-off-by: Marios Pomonis <pomonis@google.com> Reviewed-by: Andrew Honig <ahonig@google.com> Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This fixes a Spectre-v1/L1TF vulnerability in set_msr_mce() and
get_msr_mce().
Both functions contain index computations based on the
(attacker-controlled) MSR number.
Fixes: 890ca9aefa78 ("KVM: Add MCE support") Signed-off-by: Nick Finco <nifi@google.com> Signed-off-by: Marios Pomonis <pomonis@google.com> Reviewed-by: Andrew Honig <ahonig@google.com> Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[bwh: Backported to 3.16: Add #include <linux/nospec.h>] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This fixes a Spectre-v1/L1TF vulnerability in kvm_lapic_reg_write().
This function contains index computations based on the
(attacker-controlled) MSR number.
Fixes: 0105d1a52640 ("KVM: x2apic interface to lapic") Signed-off-by: Nick Finco <nifi@google.com> Signed-off-by: Marios Pomonis <pomonis@google.com> Reviewed-by: Andrew Honig <ahonig@google.com> Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[bwh: Backported to 3.16:
- Add #include <linux/nospec.h>
- Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This fixes a Spectre-v1/L1TF vulnerability in ioapic_write_indirect().
This function contains index computations based on the
(attacker-controlled) IOREGSEL register.
This patch depends on patch
"KVM: x86: Protect ioapic_read_indirect() from Spectre-v1/L1TF attacks".
Fixes: 70f93dae32ac ("KVM: Use temporary variable to shorten lines.") Signed-off-by: Nick Finco <nifi@google.com> Signed-off-by: Marios Pomonis <pomonis@google.com> Reviewed-by: Andrew Honig <ahonig@google.com> Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This fixes a Spectre-v1/L1TF vulnerability in ioapic_read_indirect().
This function contains index computations based on the
(attacker-controlled) IOREGSEL register.
Fixes: a2c118bfab8b ("KVM: Fix bounds checking in ioapic indirect register reads (CVE-2013-1798)") Signed-off-by: Nick Finco <nifi@google.com> Signed-off-by: Marios Pomonis <pomonis@google.com> Reviewed-by: Andrew Honig <ahonig@google.com> Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This fixes a Spectre-v1/L1TF vulnerability in picdev_write().
It replaces index computations based on the (attacked-controlled) port
number with constants through a minor refactoring.
Fixes: 85f455f7ddbe ("KVM: Add support for in-kernel PIC emulation") Signed-off-by: Nick Finco <nifi@google.com> Signed-off-by: Marios Pomonis <pomonis@google.com> Reviewed-by: Andrew Honig <ahonig@google.com> Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[bwh: Backported to 3.16: pic_{,un}lock() are called outside the switch] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This fixes a Spectre-v1/L1TF vulnerability in x86_decode_insn().
kvm_emulate_instruction() (an ancestor of x86_decode_insn()) is an exported
symbol, so KVM should treat it conservatively from a security perspective.
Fixes: 045a282ca415 ("KVM: emulator: implement fninit, fnstsw, fnstcw") Signed-off-by: Nick Finco <nifi@google.com> Signed-off-by: Marios Pomonis <pomonis@google.com> Reviewed-by: Andrew Honig <ahonig@google.com> Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[bwh: Backported to 3.16: Add #include <linux/nospec.h>] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot+03c4738ed29d5d366ddf@syzkaller.appspotmail.com Cc: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The task which created the MID may be gone by the time cifsd attempts to
call the callbacks on MIDs from cifs_reconnect().
This leads to a use-after-free of the task struct in cifs_wake_up_task:
==================================================================
BUG: KASAN: use-after-free in __lock_acquire+0x31a0/0x3270
Read of size 8 at addr ffff8880103e3a68 by task cifsd/630
This can be reliably reproduced by adding the below delay to
cifs_reconnect(), running find(1) on the mount, restarting the samba
server while find is running, and killing find during the delay:
Fix this by holding a reference to the task struct until the MID is
freed.
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
[bwh: Backported to 3.16:
- In _cifs_mid_q_entry_release(), use mid instead of midEntry
- Adjust context, indentation] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The loop counter addr is a u16 where as the upper limit of the loop
is an int. In the unlikely event that the il->cfg->eeprom_size is
greater than 64K then we end up with an infinite loop since addr will
wrap around an never reach upper loop limit. Fix this by making addr
an int.
Addresses-Coverity: ("Infinite loop") Fixes: be663ab67077 ("iwlwifi: split the drivers for agn and legacy devices 3945/4965") Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Stanislaw Gruszka <stf_xl@wp.pl> Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
[bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
JBD2_REC_ERR flag used to indicate the errno has been updated when jbd2
aborted, and then __ext4_abort() and ext4_handle_error() can invoke
panic if ERRORS_PANIC is specified. But if the journal has been aborted
with zero errno, jbd2_journal_abort() didn't set this flag so we can
no longer panic. Fix this by always record the proper errno in the
journal superblock.
Fixes: 4327ba52afd03 ("ext4, jbd2: ensure entering into panic after recording an error in superblock") Signed-off-by: zhangyi (F) <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20191204124614.45424-3-yi.zhang@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
We invoke jbd2_journal_abort() to abort the journal and record errno
in the jbd2 superblock when committing journal transaction besides the
failure on submitting the commit record. But there is no need for the
case and we can also invoke jbd2_journal_abort() instead of
__jbd2_journal_abort_hard().
Fixes: 818d276ceb83a ("ext4: Add the journal checksum feature") Signed-off-by: zhangyi (F) <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20191204124614.45424-2-yi.zhang@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
tracing_stat_init() was always returning '0', even on the error paths. It
now returns -ENODEV if tracing_init_dentry() fails or -ENOMEM if it fails
to created the 'trace_stat' debugfs directory.
Link: http://lkml.kernel.org/r/1410299381-20108-1-git-send-email-luis.henriques@canonical.com Fixes: ed6f1c996bfe4 ("tracing: Check return value of tracing_init_dentry()") Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
[ Pulled from the archeological digging of my INBOX ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Looking through old emails in my INBOX, I came across a patch from Luis
Henriques that attempted to fix a race of two stat tracers registering the
same stat trace (extremely unlikely, as this is done in the kernel, and
probably doesn't even exist). The submitted patch wasn't quite right as it
needed to deal with clean up a bit better (if two stat tracers were the
same, it would have the same files).
But to make the code cleaner, all we needed to do is to keep the
all_stat_sessions_mutex held for most of the registering function.
Link: http://lkml.kernel.org/r/1410299375-20068-1-git-send-email-luis.henriques@canonical.com Fixes: 002bb86d8d42f ("tracing/ftrace: separate events tracing and stats tracing engine") Reported-by: Luis Henriques <luis.henriques@canonical.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Free the vCPU's wbinvd_dirty_mask if vCPU creation fails after
kvm_arch_vcpu_init(), e.g. when installing the vCPU's file descriptor.
Do the freeing by calling kvm_arch_vcpu_free() instead of open coding
the freeing. This adds a likely superfluous, but ultimately harmless,
call to kvmclock_reset(), which only clears vcpu->arch.pv_time_enabled.
Using kvm_arch_vcpu_free() allows for additional cleanup in the future.
Fixes: f5f48ee15c2ee ("KVM: VMX: Execute WBINVD to keep data consistency with assigned devices") Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[bwh: Backported to 3.16: Also delete the preceding fx_free(), since
kvm_arch_vcpu_free() calls it.] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Explicitly free the shared page if kvmppc_mmu_init() fails during
kvmppc_core_vcpu_create(), as the page is freed only in
kvmppc_core_vcpu_free(), which is not reached via kvm_vcpu_uninit().
Fixes: 96bc451a15329 ("KVM: PPC: Introduce shared page") Reviewed-by: Greg Kurz <groug@kaod.org> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Acked-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Call kvm_vcpu_uninit() if vcore creation fails to avoid leaking any
resources allocated by kvm_vcpu_init(), i.e. the vcpu->run page.
Fixes: 371fefd6f2dc4 ("KVM: PPC: Allow book3s_hv guests to use SMT processor modes") Reviewed-by: Greg Kurz <groug@kaod.org> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Acked-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The problem with this descriptor is that it is self-referential: the
source ID of 0 matches itself! This causes the 'struct uvc_entity'
representing the display to be added to its chain list twice during
'uvc_scan_chain()': once via 'uvc_scan_chain_entity()' when it is
processed directly from the 'dev->entities' list and then again
immediately afterwards when trying to follow the source ID in
'uvc_scan_chain_forward()'
Add a check before adding an entity to a chain list to ensure that the
entity is not already part of a chain.
Link: https://lore.kernel.org/linux-media/CAAeHK+z+Si69jUR+N-SjN9q4O+o5KFiNManqEa-PjUta7EOb7A@mail.gmail.com/ Fixes: c0efd232929c ("V4L/DVB (8145a): USB Video Class driver") Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Commit f4a4cbb2047e ("USB: ir-usb: reimplement using generic framework")
switched to using the generic write implementation which may combine
multiple write requests into larger transfers. This can break the IrLAP
protocol where end-of-frame is determined using the USB short packet
mechanism, for example, if multiple frames are sent in rapid succession.
Fixes: f4a4cbb2047e ("USB: ir-usb: reimplement using generic framework") Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Commit e0d795e4f36c ("usb: irda: cleanup on ir-usb module") added a USB
IrDA header with common defines, but mistakingly switched to using the
class-descriptor baud-rate bitmask values for the outbound header.
This broke link-speed handling for rates above 9600 baud, but a device
would also be able to operate at the default 9600 baud until a
link-speed request was issued (e.g. using the TCGETS ioctl).
Fixes: e0d795e4f36c ("usb: irda: cleanup on ir-usb module") Cc: Felipe Balbi <balbi@kernel.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
projects / thirdparty / kernel / stable.git / log
