On Thursday, December 18, 2014 11:09:27 PM Richard Guy Briggs wrote:
 Eric Paris explains: Since kauditd_send_multicast_skb() gets called
in
 audit_log_end(), which can come from any context (aka even a sleeping
 context) GFP_KERNEL can't be used.  Since the audit_buffer knows what
 context it should use, pass that down and use that.
 
 See: 
https://lkml.org/lkml/2014/12/16/542
 
 BUG: sleeping function called from invalid context at mm/slab.c:2849
 in_atomic(): 1, irqs_disabled(): 0, pid: 885, name: sulogin
 2 locks held by sulogin/885:
   #0:  (&sig->cred_guard_mutex){+.+.+.}, at: [<ffffffff91152e30>]
 prepare_bprm_creds+0x28/0x8b #1:  (tty_files_lock){+.+.+.}, at:
 [<ffffffff9123e787>] selinux_bprm_committing_creds+0x55/0x22b CPU: 1 PID:
 885 Comm: sulogin Not tainted 3.18.0-next-20141216 #30 Hardware name: Dell
 Inc. Latitude E6530/07Y85M, BIOS A15 06/20/2014 ffff880223744f10
 ffff88022410f9b8 ffffffff916ba529 0000000000000375 ffff880223744f10
 ffff88022410f9e8 ffffffff91063185 0000000000000006 0000000000000000
 0000000000000000 0000000000000000 ffff88022410fa38 Call Trace:
   [<ffffffff916ba529>] dump_stack+0x50/0xa8
   [<ffffffff91063185>] ___might_sleep+0x1b6/0x1be
   [<ffffffff910632a6>] __might_sleep+0x119/0x128
   [<ffffffff91140720>] cache_alloc_debugcheck_before.isra.45+0x1d/0x1f
   [<ffffffff91141d81>] kmem_cache_alloc+0x43/0x1c9
   [<ffffffff914e148d>] __alloc_skb+0x42/0x1a3
   [<ffffffff914e2b62>] skb_copy+0x3e/0xa3
   [<ffffffff910c263e>] audit_log_end+0x83/0x100
   [<ffffffff9123b8d3>] ? avc_audit_pre_callback+0x103/0x103
   [<ffffffff91252a73>] common_lsm_audit+0x441/0x450
   [<ffffffff9123c163>] slow_avc_audit+0x63/0x67
   [<ffffffff9123c42c>] avc_has_perm+0xca/0xe3
   [<ffffffff9123dc2d>] inode_has_perm+0x5a/0x65
   [<ffffffff9123e7ca>] selinux_bprm_committing_creds+0x98/0x22b
   [<ffffffff91239e64>] security_bprm_committing_creds+0xe/0x10
   [<ffffffff911515e6>] install_exec_creds+0xe/0x79
   [<ffffffff911974cf>] load_elf_binary+0xe36/0x10d7
   [<ffffffff9115198e>] search_binary_handler+0x81/0x18c
   [<ffffffff91153376>] do_execveat_common.isra.31+0x4e3/0x7b7
   [<ffffffff91153669>] do_execve+0x1f/0x21
   [<ffffffff91153967>] SyS_execve+0x25/0x29
   [<ffffffff916c61a9>] stub_execve+0x69/0xa0
 
 Cc: stable(a)vger.kernel.org #v3.16-rc1
 Reported-by: Valdis Kletnieks <Valdis.Kletnieks(a)vt.edu>
 Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com>
 ---
  kernel/audit.c |    8 ++++----
  1 files changed, 4 insertions(+), 4 deletions(-) 
Looks good to me, thanks.
I've got this patch (and the PID filter fix) queued up to go to Linus for 
v3.19; considering that -rc1 is due on Sunday I think I'll hold this until 
early next week (targeting -rc2) just in case something nasty appears after 
the merge window closes.
 diff --git a/kernel/audit.c b/kernel/audit.c
 index 7b83c55..ce484fb 100644
 --- a/kernel/audit.c
 +++ b/kernel/audit.c
 @@ -429,7 +429,7 @@ static void kauditd_send_skb(struct sk_buff *skb)
   * This function doesn't consume an skb as might be expected since it has
 to * copy it anyways.
   */
 -static void kauditd_send_multicast_skb(struct sk_buff *skb)
 +static void kauditd_send_multicast_skb(struct sk_buff *skb, gfp_t gfp_mask)
 {
  	struct sk_buff		*copy;
  	struct audit_net	*aunet = net_generic(&init_net, audit_net_id);
 @@ -448,11 +448,11 @@ static void kauditd_send_multicast_skb(struct sk_buff
 *skb) * no reason for new multicast clients to continue with this
  	 * non-compliance.
  	 */
 -	copy = skb_copy(skb, GFP_KERNEL);
 +	copy = skb_copy(skb, gfp_mask);
  	if (!copy)
  		return;
 
 -	nlmsg_multicast(sock, copy, 0, AUDIT_NLGRP_READLOG, GFP_KERNEL);
 +	nlmsg_multicast(sock, copy, 0, AUDIT_NLGRP_READLOG, gfp_mask);
  }
 
  /*
 @@ -1949,7 +1949,7 @@ void audit_log_end(struct audit_buffer *ab)
  		struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
 
  		nlh->nlmsg_len = ab->skb->len;
 -		kauditd_send_multicast_skb(ab->skb);
 +		kauditd_send_multicast_skb(ab->skb, ab->gfp_mask);
 
  		/*
  		 * The original kaudit unicast socket sends up messages with 
-- 
paul moore
security @ redhat