On Thu, Dec 8, 2016 at 1:10 PM, Luis R. Rodriguez <mcgrof@xxxxxxxxxx> wrote: > On Thu, Dec 8, 2016 at 2:30 PM, Kees Cook <keescook@xxxxxxxxxxxx> wrote: >> On Thu, Dec 8, 2016 at 11:48 AM, Luis R. Rodriguez <mcgrof@xxxxxxxxxx> wrote: >>> While looking for early possible module loading failures I was >>> able to reproduce a memory leak possible with kmemleak. There >>> are a few rare ways to trigger a failure: >>> >>> o we've run into a failure while processing kernel parameters >>> (parse_args() returns an error) >>> o mod_sysfs_setup() fails >>> o we're a live patch module and copy_module_elf() fails >>> >>> Chances of running into this issue is really low. >>> >>> kmemleak splat: >>> >>> unreferenced object 0xffff9f2c4ada1b00 (size 32): >>> comm "kworker/u16:4", pid 82, jiffies 4294897636 (age 681.816s) >>> hex dump (first 32 bytes): >>> 6d 65 6d 73 74 69 63 6b 30 00 00 00 00 00 00 00 memstick0....... >>> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ >>> backtrace: >>> [<ffffffff8c6cfeba>] kmemleak_alloc+0x4a/0xa0 >>> [<ffffffff8c200046>] __kmalloc_track_caller+0x126/0x230 >>> [<ffffffff8c1bc581>] kstrdup+0x31/0x60 >>> [<ffffffff8c1bc5d4>] kstrdup_const+0x24/0x30 >>> [<ffffffff8c3c23aa>] kvasprintf_const+0x7a/0x90 >>> [<ffffffff8c3b5481>] kobject_set_name_vargs+0x21/0x90 >>> [<ffffffff8c4fbdd7>] dev_set_name+0x47/0x50 >>> [<ffffffffc07819e5>] memstick_check+0x95/0x33c [memstick] >>> [<ffffffff8c09c893>] process_one_work+0x1f3/0x4b0 >>> [<ffffffff8c09cb98>] worker_thread+0x48/0x4e0 >>> [<ffffffff8c0a2b79>] kthread+0xc9/0xe0 >>> [<ffffffff8c6dab5f>] ret_from_fork+0x1f/0x40 >>> [<ffffffffffffffff>] 0xffffffffffffffff >>> >>> Signed-off-by: Luis R. Rodriguez <mcgrof@xxxxxxxxxx> >> >> Acked-by: Kees Cook <keescook@xxxxxxxxxxxx> >> >> Is this worth sending through -stable too? > > Yes, for some reason git-send e-mail complained to me about > stable@xxxxxxxxxx not being a valid local address, so I had to remove > it, but indeed. I'll try to fix this e-mail issue later and add your > tag. Yup, you want stable@xxxxxxxxxxxxxxx. :) -Kees -- Kees Cook Nexus Security -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
