As part of y2038 solution, all internal uses of
struct timeval are replaced by struct __kernel_old_timeval
and struct compat_timeval by struct old_timeval32.
Make socket timestamps use these new types.
This is mainly to be able to verify that the kernel build
is y2038 safe when such non y2038 safe types are not
supported anymore.
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Cc: isdn@linux-pingi.de
Signed-off-by: David S. Miller <davem@davemloft.net>
A recent commit in Clang expanded the -Wstring-plus-int warning, showing
some odd behavior in this file.
drivers/isdn/hardware/avm/b1.c:426:30: warning: adding 'int' to a string does not append to the string [-Wstring-plus-int]
cinfo->version[j] = "\0\0" + 1;
~~~~~~~^~~
drivers/isdn/hardware/avm/b1.c:426:30: note: use array indexing to silence this warning
cinfo->version[j] = "\0\0" + 1;
^
& [ ]
1 warning generated.
This is equivalent to just "\0". Nick pointed out that it is smarter to
use "" instead of "\0" because "" is used elsewhere in the kernel and
can be deduplicated at the linking stage.
Link: https://github.com/ClangBuiltLinux/linux/issues/309
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
One of the more common cases of allocation size calculations is finding the
size of a structure that has a zero-sized array at the end, along with memory
for some number of elements for that array. For example:
struct foo {
int stuff;
void *entry[];
};
instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);
Instead of leaving these open-coded and prone to type mistakes, we can now
use the new struct_size() helper:
instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The functions isdn_tty_tiocmset() and isdn_tty_set_termios() may be
concurrently executed.
isdn_tty_tiocmset
isdn_tty_modem_hup
line 719: kfree(info->dtmf_state);
line 721: kfree(info->silence_state);
line 723: kfree(info->adpcms);
line 725: kfree(info->adpcmr);
isdn_tty_set_termios
isdn_tty_modem_hup
line 719: kfree(info->dtmf_state);
line 721: kfree(info->silence_state);
line 723: kfree(info->adpcms);
line 725: kfree(info->adpcmr);
Thus, some concurrency double-free bugs may occur.
These possible bugs are found by a static tool written by myself and
my manual code review.
To fix these possible bugs, the mutex lock "modem_info_mutex" used in
isdn_tty_tiocmset() is added in isdn_tty_set_termios().
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In drivers/isdn/hisax/hfc_pci.c, the functions hfcpci_interrupt() and
HFCPCI_l1hw() may be concurrently executed.
HFCPCI_l1hw()
line 1173: if (!cs->tx_skb)
hfcpci_interrupt()
line 942: spin_lock_irqsave();
line 1066: dev_kfree_skb_irq(cs->tx_skb);
Thus, a possible concurrency use-after-free bug may occur
in HFCPCI_l1hw().
To fix these bugs, the calls to spin_lock_irqsave() and
spin_unlock_irqrestore() are added in HFCPCI_l1hw(), to protect the
access to cs->tx_skb.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixes gcc '-Wunused-but-set-variable' warning:
drivers/isdn/hisax/hfc_pci.c:277:6: warning:
variable ‘total’ set but not used [-Wunused-but-set-variable]
It never used since git history start.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The PCI vendor id of U.S. Robotics isn't defined in pci_ids.h so far,
only ISDN driver w6692 has a private definition. Move the definition
to pci_ids.h and use it in the r8169 driver too.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I started looking at the history of this driver, and last time the
maintainer was active on the mailing list was when discussing how to
remove it. This was in 2012:
https://lore.kernel.org/lkml/4F4DE175.30002@melware.de/
It looks to me like this has in practice been an orphan for quite a while.
It's throwing warnings about stack size in a function that is in dire
need of refactoring, and it's probably a case of "it's time to call it".
Cc: Armin Schindler <mac@melware.de>
Cc: Karsten Keil <isdn@linux-pingi.de>
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull AFS updates from Al Viro:
"AFS series, with some iov_iter bits included"
* 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits)
missing bits of "iov_iter: Separate type from direction and use accessor functions"
afs: Probe multiple fileservers simultaneously
afs: Fix callback handling
afs: Eliminate the address pointer from the address list cursor
afs: Allow dumping of server cursor on operation failure
afs: Implement YFS support in the fs client
afs: Expand data structure fields to support YFS
afs: Get the target vnode in afs_rmdir() and get a callback on it
afs: Calc callback expiry in op reply delivery
afs: Fix FS.FetchStatus delivery from updating wrong vnode
afs: Implement the YFS cache manager service
afs: Remove callback details from afs_callback_break struct
afs: Commit the status on a new file/dir/symlink
afs: Increase to 64-bit volume ID and 96-bit vnode ID for YFS
afs: Don't invoke the server to read data beyond EOF
afs: Add a couple of tracepoints to log I/O errors
afs: Handle EIO from delivery function
afs: Fix TTL on VL server and address lists
afs: Implement VL server rotation
afs: Improve FS server rotation error handling
...
Pull tty ioctl updates from Al Viro:
"This is the compat_ioctl work related to tty ioctls.
Quite a bit of dead code taken out, all tty-related stuff gone from
fs/compat_ioctl.c. A bunch of compat bugs fixed - some still remain,
but all more or less generic tty-related ioctls should be covered
(remaining issues are in things like driver-private ioctls in a pcmcia
serial card driver not getting properly handled in 32bit processes on
64bit host, etc)"
* 'work.tty-ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (53 commits)
kill TIOCSERGSTRUCT
change semantics of ldisc ->compat_ioctl()
kill TIOCSER[SG]WILD
synclink_gt(): fix compat_ioctl()
pty: fix compat ioctls
compat_ioctl - kill keyboard ioctl handling
gigaset: add ->compat_ioctl()
vt_compat_ioctl(): clean up, use compat_ptr() properly
gigaset: don't try to printk userland buffer contents
dgnc: don't bother with (empty) stub for TCXONC
dgnc: leave TIOC[GS]SOFTCAR to ldisc
remove fallback to drivers for TIOCGICOUNT
dgnc: break-related ioctls won't reach ->ioctl()
kill the rest of tty COMPAT_IOCTL() entries
dgnc: TIOCM... won't reach ->ioctl()
isdn_tty: TCSBRK{,P} won't reach ->ioctl()
kill capinc_tty_ioctl()
take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()
synclink: reduce pointless checks in ->ioctl()
complete ->[sg]et_serial() switchover
...
In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.
Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements. This makes it easier to add further
iterator types. Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.
Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself. Only the direction is required.
Signed-off-by: David Howells <dhowells@redhat.com>
Clang warns (trimmed for brevity):
drivers/isdn/mISDN/tei.c:1193:7: warning: overflow converting case value
to switch condition type (2147764552 to 18446744071562348872) [-Wswitch]
case IMHOLD_L1:
^
drivers/isdn/mISDN/tei.c:1187:7: warning: overflow converting case value
to switch condition type (2147764550 to 18446744071562348870) [-Wswitch]
case IMCLEAR_L2:
^
2 warnings generated.
The root cause is that the _IOC macro can generate really large numbers,
which don't find into type int. My research into how GCC and Clang are
handling this at a low level didn't prove fruitful and surveying the
kernel tree shows that aside from here and a few places in the scsi
subsystem, everything that uses _IOC is at least of type 'unsigned int'.
Make that change here because as nothing in this function cares about
the signedness of the variable and it removes ambiguity, which is never
good when dealing with compilers.
While we're here, remove the unnecessary local variable ret (just return
-EINVAL and 0 directly).
Link: https://github.com/ClangBuiltLinux/linux/issues/67
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Clang warns:
drivers/isdn/hisax/hfc_pci.c:131:34: error: if statement has empty body
[-Werror,-Wempty-body]
if (Read_hfc(cs, HFCPCI_INT_S1));
^
drivers/isdn/hisax/hfc_pci.c:131:34: note: put the semicolon on a
separate line to silence this warning
In my attempt to hide the warnings because I thought they didn't serve
any purpose[1], Masahiro Yamada pointed out that {Read,Write}_hfc in
hci_pci.c should be using a standard register access method; otherwise,
the compiler will just remove the if statements.
For hfc_pci, use the versions of {Read,Write}_hfc found in
drivers/isdn/hardware/mISDN/hfc_pCI.h while converting pci_io to be
'void __iomem *' (and clean up ioremap) then remove the empty if
statements.
For hfc_sx, {Read,Write}_hfc are already use a proper register accessor
(inb, outb) so just remove the unnecessary if statements.
[1]: https://lore.kernel.org/lkml/20181016021454.11953-1-natechancellor@gmail.com/
Link: https://github.com/ClangBuiltLinux/linux/issues/66
Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
kill the long-dead code - it's been unreachable since 2008. Redundant, as
well - generic will do exact same thing, since ->break_ctl is NULL here...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Clang warns when multiple sets of parentheses are used for a single
conditional statement.
drivers/isdn/hisax/amd7930_fn.c:628:32: warning: equality comparison
with extraneous parentheses [-Wparentheses-equality]
if ((cs->dc.amd7930.ph_state == 8)) {
~~~~~~~~~~~~~~~~~~~~~~~~^~~~
drivers/isdn/hisax/amd7930_fn.c:628:32: note: remove extraneous
parentheses around the comparison to silence this warning
if ((cs->dc.amd7930.ph_state == 8)) {
~ ^ ~
drivers/isdn/hisax/amd7930_fn.c:628:32: note: use '=' to turn this
equality comparison into an assignment
if ((cs->dc.amd7930.ph_state == 8)) {
^~
=
1 warning generated.
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Notice that in this particular case, I replaced the
"--v-- fall through --v--" comment with a proper
"fall through", which is what GCC is expecting to
find.
This fix is part of the ongoing efforts to enabling
-Wimplicit-fallthrough
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace "--v-- fall through --v--" with a proper "fall through"
annotation. Also, change "bad cid: fall through" to
"fall through - bad cid".
This fix is part of the ongoing efforts to enabling -Wimplicit-fallthrough
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
Notice that in this particular case, I replaced the
" --v-- fall through --v-- " comment with a proper
"fall through", which is what GCC is expecting to find.
Addresses-Coverity-ID: 1364476 ("Missing break in switch")
Addresses-Coverity-ID: 1364477 ("Missing break in switch")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace "fallthru" with a proper "fall through" annotation.
This fix is part of the ongoing efforts to enabling
-Wimplicit-fallthrough
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
kfree_skb has taken the null pointer into account. hence it is safe
to remove the redundant null pointer check before kfree_skb.
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Clang warns when more than one set of parentheses are used for single
conditional statements:
drivers/isdn/hisax/w6692.c:627:30: warning: equality comparison with
extraneous parentheses [-Wparentheses-equality]
if ((cs->dc.w6692.ph_state == W_L1IND_DRD)) {
~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~
drivers/isdn/hisax/w6692.c:627:30: note: remove extraneous parentheses
around the comparison to silence this warning
if ((cs->dc.w6692.ph_state == W_L1IND_DRD)) {
~ ^ ~
drivers/isdn/hisax/w6692.c:627:30: note: use '=' to turn this equality
comparison into an assignment
if ((cs->dc.w6692.ph_state == W_L1IND_DRD)) {
^~
=
1 warning generated.
Remove the parentheses to silence this warning.
Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It was possible to directly leak the kernel address where the isdn_dev
structure pointer was stored. This is a kernel ASLR bypass for anyone
with access to the ioctl. The code had been present since the beginning
of git history, though this shouldn't ever be needed for normal operation,
therefore remove it.
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Karsten Keil <isdn@linux-pingi.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
hisax_cs_new() and hisax_cs_setup() are never called in atomic context.
They call kmalloc() and kzalloc() with GFP_ATOMIC, which is not necessary.
GFP_ATOMIC can be replaced with GFP_KERNEL.
This is found by a static analysis tool named DCNS written by myself.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
init_PStack() is never called in atomic context.
It calls kmalloc() with GFP_ATOMIC, which is not necessary.
GFP_ATOMIC can be replaced with GFP_KERNEL.
This is found by a static analysis tool named DCNS written by myself.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
nj_probe() is never called in atomic context.
It calls kzalloc() with GFP_ATOMIC, which is not necessary.
GFP_ATOMIC can be replaced with GFP_KERNEL.
This is found by a static analysis tool named DCNS written by myself.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
hfc_probe() is never called in atomic context.
It calls kzalloc() with GFP_ATOMIC, which is not necessary.
GFP_ATOMIC can be replaced with GFP_KERNEL.
This is found by a static analysis tool named DCNS written by myself.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix build warnings in drivers/isdn/capi/ when CONFIG_PROC_FS is not
enabled by marking the unused functions as __maybe_unused.
../drivers/isdn/capi/capi.c:1324:12: warning: 'capi20_proc_show' defined but not used [-Wunused-function]
../drivers/isdn/capi/capi.c:1347:12: warning: 'capi20ncci_proc_show' defined but not used [-Wunused-function]
../drivers/isdn/capi/capidrv.c:2454:12: warning: 'capidrv_proc_show' defined but not used [-Wunused-function]
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: isdn4linux@listserv.isdn4linux.de (subscribers-only)
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
Warning level 2 was used: -Wimplicit-fallthrough=2
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Simple overlapping changes in stmmac driver.
Adjust skb_gro_flush_final_remcsum function signature to make GRO list
changes in net-next, as per Stephen Rothwell's example merge
resolution.
Signed-off-by: David S. Miller <davem@davemloft.net>
gcc 8.1.0 complains:
drivers/isdn/i4l/isdn_tty.c: In function 'isdn_tty_suspend.isra.1':
drivers/isdn/i4l/isdn_tty.c:790:3: warning:
'strncpy' output truncated before terminating nul copying
as many bytes from a string as its length
drivers/isdn/i4l/isdn_tty.c:778:6: note: length computed here
drivers/isdn/i4l/isdn_tty.c: In function 'isdn_tty_resume':
drivers/isdn/i4l/isdn_tty.c:880:3: warning:
'strncpy' output truncated before terminating nul copying
as many bytes from a string as its length
drivers/isdn/i4l/isdn_tty.c:817:6: note: length computed here
Using strncpy() is indeed less than perfect since the length of data to
be copied has already been determined with strlen(). Replace strncpy()
with memcpy() to address the warning and optimize the code a little.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The poll() changes were not well thought out, and completely
unexplained. They also caused a huge performance regression, because
"->poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.
Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"->get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead. That gets rid of one of the new indirections.
But that doesn't fix the new complexity that is completely unwarranted
for the regular case. The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.
[ This revert is a revert of about 30 different commits, not reverted
individually because that would just be unnecessarily messy - Linus ]
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The USB completion callback does not disable interrupts while acquiring
the ->lock. We want to remove the local_irq_disable() invocation from
__usb_hcd_giveback_urb() and therefore it is required for the callback
handler to disable the interrupts while acquiring the lock.
The callback may be invoked either in IRQ or BH context depending on the
USB host controller.
Use the _irqsave() variant of the locking primitives.
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: netdev@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Using usb_fill_int_urb() helps to find code which initializes an
URB. A grep for members of the struct (like ->complete) reveal lots
of other things, too.
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: netdev@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Using usb_fill_int_urb() helps to find code which initializes an
URB. A grep for members of the struct (like ->complete) reveal lots
of other things, too.
The `interval' parameter is now set differently on HS and SS. The
argument is fed from bInterval so it should be the right thing to do.
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: netdev@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Using usb_fill_int_urb() helps to find code which initializes an
URB. A grep for members of the struct (like ->complete) reveal lots
of other things, too.
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: gigaset307x-common@lists.sourceforge.net
Cc: netdev@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull aio updates from Al Viro:
"Majority of AIO stuff this cycle. aio-fsync and aio-poll, mostly.
The only thing I'm holding back for a day or so is Adam's aio ioprio -
his last-minute fixup is trivial (missing stub in !CONFIG_BLOCK case),
but let it sit in -next for decency sake..."
* 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
aio: sanitize the limit checking in io_submit(2)
aio: fold do_io_submit() into callers
aio: shift copyin of iocb into io_submit_one()
aio_read_events_ring(): make a bit more readable
aio: all callers of aio_{read,write,fsync,poll} treat 0 and -EIOCBQUEUED the same way
aio: take list removal to (some) callers of aio_complete()
aio: add missing break for the IOCB_CMD_FDSYNC case
random: convert to ->poll_mask
timerfd: convert to ->poll_mask
eventfd: switch to ->poll_mask
pipe: convert to ->poll_mask
crypto: af_alg: convert to ->poll_mask
net/rxrpc: convert to ->poll_mask
net/iucv: convert to ->poll_mask
net/phonet: convert to ->poll_mask
net/nfc: convert to ->poll_mask
net/caif: convert to ->poll_mask
net/bluetooth: convert to ->poll_mask
net/sctp: convert to ->poll_mask
net/tipc: convert to ->poll_mask
...
In divasmain.c, the function divas_write() firstly invokes the function
diva_xdi_open_adapter() to open the adapter that matches with the adapter
number provided by the user, and then invokes the function diva_xdi_write()
to perform the write operation using the matched adapter. The two functions
diva_xdi_open_adapter() and diva_xdi_write() are located in diva.c.
In diva_xdi_open_adapter(), the user command is copied to the object 'msg'
from the userspace pointer 'src' through the function pointer 'cp_fn',
which eventually calls copy_from_user() to do the copy. Then, the adapter
number 'msg.adapter' is used to find out a matched adapter from the
'adapter_queue'. A matched adapter will be returned if it is found.
Otherwise, NULL is returned to indicate the failure of the verification on
the adapter number.
As mentioned above, if a matched adapter is returned, the function
diva_xdi_write() is invoked to perform the write operation. In this
function, the user command is copied once again from the userspace pointer
'src', which is the same as the 'src' pointer in diva_xdi_open_adapter() as
both of them are from the 'buf' pointer in divas_write(). Similarly, the
copy is achieved through the function pointer 'cp_fn', which finally calls
copy_from_user(). After the successful copy, the corresponding command
processing handler of the matched adapter is invoked to perform the write
operation.
It is obvious that there are two copies here from userspace, one is in
diva_xdi_open_adapter(), and one is in diva_xdi_write(). Plus, both of
these two copies share the same source userspace pointer, i.e., the 'buf'
pointer in divas_write(). Given that a malicious userspace process can race
to change the content pointed by the 'buf' pointer, this can pose potential
security issues. For example, in the first copy, the user provides a valid
adapter number to pass the verification process and a valid adapter can be
found. Then the user can modify the adapter number to an invalid number.
This way, the user can bypass the verification process of the adapter
number and inject inconsistent data.
This patch reuses the data copied in
diva_xdi_open_adapter() and passes it to diva_xdi_write(). This way, the
above issues can be avoided.
Signed-off-by: Wenwen Wang <wang6495@umn.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixes: 2cd1f0ddbb ("isdn: replace ->proc_fops with ->proc_show")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
