summaryrefslogtreecommitdiffstats
path: root/crypto/algboss.c
AgeCommit message (Collapse)AuthorFilesLines
2013-06-25crypto: algboss - Hold ref count on larvalHerbert Xu1-7/+8
On Thu, Jun 20, 2013 at 10:00:21AM +0200, Daniel Borkmann wrote: > After having fixed a NULL pointer dereference in SCTP 1abd165e ("net: > sctp: fix NULL pointer dereference in socket destruction"), I ran into > the following NULL pointer dereference in the crypto subsystem with > the same reproducer, easily hit each time: > > BUG: unable to handle kernel NULL pointer dereference at (null) > IP: [<ffffffff81070321>] __wake_up_common+0x31/0x90 > PGD 0 > Oops: 0000 [#1] SMP > Modules linked in: padlock_sha(F-) sha256_generic(F) sctp(F) libcrc32c(F) [..] > CPU: 6 PID: 3326 Comm: cryptomgr_probe Tainted: GF 3.10.0-rc5+ #1 > Hardware name: Dell Inc. PowerEdge T410/0H19HD, BIOS 1.6.3 02/01/2011 > task: ffff88007b6cf4e0 ti: ffff88007b7cc000 task.ti: ffff88007b7cc000 > RIP: 0010:[<ffffffff81070321>] [<ffffffff81070321>] __wake_up_common+0x31/0x90 > RSP: 0018:ffff88007b7cde08 EFLAGS: 00010082 > RAX: ffffffffffffffe8 RBX: ffff88003756c130 RCX: 0000000000000000 > RDX: 0000000000000000 RSI: 0000000000000003 RDI: ffff88003756c130 > RBP: ffff88007b7cde48 R08: 0000000000000000 R09: ffff88012b173200 > R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000282 > R13: ffff88003756c138 R14: 0000000000000000 R15: 0000000000000000 > FS: 0000000000000000(0000) GS:ffff88012fc60000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b > CR2: 0000000000000000 CR3: 0000000001a0b000 CR4: 00000000000007e0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 > Stack: > ffff88007b7cde28 0000000300000000 ffff88007b7cde28 ffff88003756c130 > 0000000000000282 ffff88003756c128 ffffffff81227670 0000000000000000 > ffff88007b7cde78 ffffffff810722b7 ffff88007cdcf000 ffffffff81a90540 > Call Trace: > [<ffffffff81227670>] ? crypto_alloc_pcomp+0x20/0x20 > [<ffffffff810722b7>] complete_all+0x47/0x60 > [<ffffffff81227708>] cryptomgr_probe+0x98/0xc0 > [<ffffffff81227670>] ? crypto_alloc_pcomp+0x20/0x20 > [<ffffffff8106760e>] kthread+0xce/0xe0 > [<ffffffff81067540>] ? kthread_freezable_should_stop+0x70/0x70 > [<ffffffff815450dc>] ret_from_fork+0x7c/0xb0 > [<ffffffff81067540>] ? kthread_freezable_should_stop+0x70/0x70 > Code: 41 56 41 55 41 54 53 48 83 ec 18 66 66 66 66 90 89 75 cc 89 55 c8 > 4c 8d 6f 08 48 8b 57 08 41 89 cf 4d 89 c6 48 8d 42 e > RIP [<ffffffff81070321>] __wake_up_common+0x31/0x90 > RSP <ffff88007b7cde08> > CR2: 0000000000000000 > ---[ end trace b495b19270a4d37e ]--- > > My assumption is that the following is happening: the minimal SCTP > tool runs under ``echo 1 > /proc/sys/net/sctp/auth_enable'', hence > it's making use of crypto_alloc_hash() via sctp_auth_init_hmacs(). > It forks itself, heavily allocates, binds, listens and waits in > accept on sctp sockets, and then randomly kills some of them (no > need for an actual client in this case to hit this). Then, again, > allocating, binding, etc, and then killing child processes. > > The problem that might be happening here is that cryptomgr requests > the module to probe/load through cryptomgr_schedule_probe(), but > before the thread handler cryptomgr_probe() returns, we return from > the wait_for_completion_interruptible() function and probably already > have cleared up larval, thus we run into a NULL pointer dereference > when in cryptomgr_probe() complete_all() is being called. > > If we wait with wait_for_completion() instead, this panic will not > occur anymore. This is valid, because in case a signal is pending, > cryptomgr_probe() returns from probing anyway with properly calling > complete_all(). The use of wait_for_completion_interruptible is intentional so that we don't lock up the thread if a bug causes us to never wake up. This bug is caused by the helper thread using the larval without holding a reference count on it. If the helper thread completes after the original thread requesting for help has gone away and destroyed the larval, then we get the crash above. So the fix is to hold a reference count on the larval. Cc: <stable@vger.kernel.org> # 3.6+ Reported-by: Daniel Borkmann <dborkman@redhat.com> Tested-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-06-27crypto: algapi - Fix hang on crypto allocationSteffen Klassert1-1/+1
git commit 398710379 (crypto: algapi - Move larval completion into algboss) replaced accidentally a call to complete_all() by a call to complete(). This causes a hang on crypto allocation if we have more than one larval waiter. This pach restores the call to complete_all(). Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-06-22crypto: algapi - Move larval completion into algbossHerbert Xu1-8/+9
It has been observed that sometimes the crypto allocation code will get stuck for 60 seconds or multiples thereof. This is usually caused by an algorithm failing to pass the self-test. If an algorithm fails to be constructed, we will immediately notify all larval waiters. However, if it succeeds in construction, but then fails the self-test, we won't notify anyone at all. This patch fixes this by merging the notification in the case where the algorithm fails to be constructed with that of the the case where it pases the self-test. This way regardless of what happens, we'll give the larval waiters an answer. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-08-06crypto: testmgr - Fix test disabling optionHerbert Xu1-4/+4
This patch fixes a serious bug in the test disabling patch where it can cause an spurious load of the cryptomgr module even when it's compiled in. It also negates the test disabling option so that its absence causes tests to be enabled. The Kconfig option is also now behind EMBEDDED. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-06-03crypto: testmgr - add an option to disable cryptoalgos' self-testsAlexander Shishkin1-0/+4
By default, CONFIG_CRYPTO_MANAGER_TESTS will be enabled and thus self-tests will still run, but it is now possible to disable them to gain some time during bootup. Signed-off-by: Alexander Shishkin <virtuoso@slind.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo1-0/+1
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2009-07-07crypto: api - Add new template create functionHerbert Xu1-0/+5
This patch introduces the template->create function intended to replace the existing alloc function. The intention is for create to handle the registration directly, whereas currently the caller of alloc has to handle the registration. This allows type-specific code to be run prior to registration. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-06-02crypto: testmgr - Dynamically allocate xbuf and axbufHerbert Xu1-17/+1
We currently allocate temporary memory that is used for testing statically. This renders the testing engine non-reentrant. As algorithms may nest, i.e., one may construct another in order to carry out a part of its operation, this is unacceptable. For example, it has been reported that an AEAD implementation allocates a cipher in its setkey function, which causes it to fail during testing as the temporary memory is overwritten. This patch replaces the static memory with dynamically allocated buffers. We need a maximum of 16 pages so this slightly increases the chances of an algorithm failing due to memory shortage. However, as testing usually occurs at registration, this shouldn't be a big problem. Reported-by: Shasi Pulijala <spulijala@amcc.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-02-18crypto: testmgr - Test skciphers with no IVsHerbert Xu1-4/+16
As it is an skcipher with no IV escapes testing altogether because we only test givcipher objects. This patch fixes the bypass logic to test these algorithms. Conversely, we're currently testing nivaead algorithms with IVs, which would have deadlocked had it not been for the fact that no nivaead algorithms have any test vectors. This patch also fixes that case. Both fixes are ugly as hell, but this ugliness should hopefully disappear once we move them into the per-type code (i.e., the AEAD test would live in aead.c and the skcipher stuff in ablkcipher.c). Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-08-29crypto: cryptomgr - Test ciphers using ECBHerbert Xu1-4/+1
As it is we only test ciphers when combined with a mode. That means users that do not invoke a mode of operations may get an untested cipher. This patch tests all ciphers using the ECB mode so that simple cipher users such as ansi-cprng are also protected. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-08-29crypto: api - Use test infrastructureHerbert Xu1-5/+70
This patch makes use of the new testing infrastructure by requiring algorithms to pass a run-time test before they're made available to users. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-08-29crypto: cryptomgr - Add test infrastructureHerbert Xu1-0/+238
This patch moves the newly created alg_test infrastructure into cryptomgr. This shall allow us to use it for testing at algorithm registrations. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>