| Commit message (Collapse) | Author | Age | Files | Lines |
|---|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
I wanted to wrap a bunch of ida_simple_get calls into their own locking,
until I dug around and read the original commit message. Stuff like
this should imo be added to the kernel doc, let's do that.
Link: http://lkml.kernel.org/r/20161027072216.20411-1-daniel.vetter@ffwll.ch
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
I'm working on address sanitizer project for kernel. Recently we
started experiments with stack instrumentation, to detect out-of-bounds
read/write bugs on stack.
Just after booting I've hit out-of-bounds read on stack in idr_for_each
(and in __idr_remove_all as well):
struct idr_layer **paa = &pa[0];
while (id >= 0 && id <= max) {
...
while (n < fls(id)) {
n += IDR_BITS;
p = *--paa; <--- here we are reading pa[-1] value.
}
}
Despite the fact that after this dereference we are exiting out of loop
and never use p, such behaviour is undefined and should be avoided.
Fix this by moving pointer derference to the beggining of the loop,
right before we will use it.
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Alexey Preobrazhensky <preobr@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
| |
|
|
|
|
|
|
|
| |
If "idr->hint == p" is true, it also implies "idr->hint" is true(not NULL).
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
| |
|
|
|
|
|
|
|
|
|
| |
After idr subsystem is changed to RCU-awared, the free layer will not go
to the free list. The free list will not be filled up when
idr_remove(). So we don't need to shink it too.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
| |
When the smaller id is not found, idr_replace() returns -ENOENT. But
when the id is bigger enough, idr_replace() returns -EINVAL, actually
there is no difference between these two kinds of ids.
These are all unallocated id, the return values of the idr_replace() for
these ids should be the same: -ENOENT.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
If the ida has at least one existing id, and when an unallocated ID
which meets a certain condition is passed to the ida_remove(), the
system will crash because it hits NULL pointer dereference.
The condition is that the unallocated ID shares the same lowest idr
layer with the existing ID, but the idr slot would be different if the
unallocated ID were to be allocated.
In this case the matching idr slot for the unallocated_id is NULL,
causing @bitmap to be NULL which the function dereferences without
checking crashing the kernel.
See the test code:
static void test3(void)
{
int id;
DEFINE_IDA(test_ida);
printk(KERN_INFO "Start test3\n");
if (ida_pre_get(&test_ida, GFP_KERNEL) < 0) return;
if (ida_get_new(&test_ida, &id) < 0) return;
ida_remove(&test_ida, 4000); /* bug: null deference here */
printk(KERN_INFO "End of test3\n");
}
It happens only when the caller tries to free an unallocated ID which is
the caller's fault. It is not a bug. But it is better to add the
proper check and complain rather than crashing the kernel.
[tj@kernel.org: updated patch description]
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
If unallocated_id = (ANY * idr_max(idp->layers) + existing_id) is passed
to idr_remove(). The existing_id will be removed unexpectedly.
The following test shows this unexpected id-removal:
static void test4(void)
{
int id;
DEFINE_IDR(test_idr);
printk(KERN_INFO "Start test4\n");
id = idr_alloc(&test_idr, (void *)1, 42, 43, GFP_KERNEL);
BUG_ON(id != 42);
idr_remove(&test_idr, 42 + IDR_SIZE);
TEST_BUG_ON(idr_find(&test_idr, 42) != (void *)1);
idr_destroy(&test_idr);
printk(KERN_INFO "End of test4\n");
}
ida_remove() shares the similar problem.
It happens only when the caller tries to free an unallocated ID which is
the caller's fault. It is not a bug. But it is better to add the
proper check and complain rather than removing an existing_id silently.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
Replace rcu_assign_pointer(x, NULL) with RCU_INIT_POINTER(x, NULL)
The rcu_assign_pointer() ensures that the initialization of a structure
is carried out before storing a pointer to that structure. And in the
case of the NULL pointer, there is no structure to initialize.
So, rcu_assign_pointer(p, NULL) can be safely converted to
RCU_INIT_POINTER(p, NULL)
Signed-off-by: Monam Agarwal <monamagarwal123@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
Remove no longer used deprecated code, and make local functions
static.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Jeff Layton <jlayton@redhat.com>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: George Spelvin <linux@horizon.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
| |
|
|
|
| |
Signed-off-by: Andreas Gruenbacher <agruen@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
|
| |
|
|
|
|
|
|
|
|
|
|
|
| |
We print a dump stack after idr_remove warning. This is useful to find
the faulty piece of code. Let's do the same for ida_remove, as it would
be equally useful there.
[akpm@linux-foundation.org: convert the open-coded printk+dump_stack into WARN()]
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Cc: Tejun Heo <tj@kernel.org>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
| |
|
|
|
|
|
|
|
|
| |
This patch fix spelling typo found in DocBook/kernel-api.xml.
It is because the file is generated from the source comments,
I have to fix the comments in source codes.
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
|
| |
|
