crypto: shash - Fix a sleep-in-atomic bug in shash_setkey_unaligned
commit79d47dd686d09ad32af1ad2f9191dbc43909bf86
authorJia-Ju Bai <baijiaju1990@163.com>
Tue, 3 Oct 2017 02:25:22 +0000 (3 10:25 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 10 Nov 2018 15:42:59 +0000 (10 07:42 -0800)
treefd57eb68a5cdc7787a706883a33869af485286cd
parenteba69ae2afef955377e17b746ef14c5a245f4bdb
crypto: shash - Fix a sleep-in-atomic bug in shash_setkey_unaligned

[ Upstream commit 9039f3ef446e9ffa200200c934f049add9e58426 ]

The SCTP program may sleep under a spinlock, and the function call path is:
sctp_generate_t3_rtx_event (acquire the spinlock)
  sctp_do_sm
    sctp_side_effects
      sctp_cmd_interpreter
        sctp_make_init_ack
          sctp_pack_cookie
            crypto_shash_setkey
              shash_setkey_unaligned
                kmalloc(GFP_KERNEL)

For the same reason, the orinoco driver may sleep in interrupt handler,
and the function call path is:
orinoco_rx_isr_tasklet
  orinoco_rx
    orinoco_mic
      crypto_shash_setkey
        shash_setkey_unaligned
          kmalloc(GFP_KERNEL)

To fix it, GFP_KERNEL is replaced with GFP_ATOMIC.
This bug is found by my static analysis tool and my code review.

Signed-off-by: Jia-Ju Bai <baijiaju1990@163.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
crypto/shash.c