Re: [PATCH] audit: grab a reference to context->pwd when it's cached

On Fri, Oct 5, 2012 at 9:15 AM, Jeff Layton <jlayton(a)redhat.com&gt; wrote: >> >> ------------[ cut here ]------------ >> kernel BUG at fs/buffer.c:1220! >> invalid opcode: 0000 [#1] SMP >> CPU 0 >> Pid: 3683, comm: a.out Not tainted 3.5.0 #3 >> RIP: e030:[<ffffffff816a99f4>] [<ffffffff816a99f4>] >> check_irqs_on.part.8+0x4/0x6 >> RSP: e02b:ffff8807b156dc28 EFLAGS: 00010046 >> RAX: ffff8807d0dd0000 RBX: ffff8807a7d6df28 RCX: 0000000005883396 >> RDX: 0000000000001000 RSI: 0000000005883396 RDI: ffff8807cfc0c000 >> RBP: ffff8807b156dc28 R08: 0000000000000001 R09: ffff8807a7d6de50 >> R10: f83a2b0a359bf007 R11: 0000000000000000 R12: ffff8807a7d6de54 >> R13: ffff8807a7d6de80 R14: ffff8807cfc1f120 R15: 0000000005883396 >> FS: 00007f97164ec700(0000) GS:ffff8807ffc00000(0063) knlGS:0000000000000000 >> CS: e033 DS: 002b ES: 002b CR0: 000000008005003b >> CR2: 00000000f76ca3b0 CR3: 00000007bbb53000 CR4: 0000000000002660 >> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 >> DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 >> Process a.out (pid: 3683, threadinfo ffff8807b156c000, task ffff8807bbae8000) >> Stack: >> ffff8807b156dc98 ffffffff8116a099 ffff8807b59f3000 ffff8807b156dd30 >> ffff8807b156dd60 ffff8807b156de78 ffff8807b156dc78 ffffffff816af231 >> ffff8807b156dcd8 ffff8807a7d6e538 ffff8807a7d6df28 ffff8807a7d6de54 >> Call Trace: >> [<ffffffff8116a099>] __find_get_block+0x1f9/0x200 >> [<ffffffff816af231>] ? down_read+0x11/0x30 >> [<ffffffff811d1405>] ext3_clear_blocks+0x75/0x140 >> [<ffffffff811d15dc>] ext3_free_data+0x10c/0x150 >> [<ffffffff811e2061>] ? ext3_journal_start_sb+0x31/0x60 >> [<ffffffff811d1cb5>] ext3_truncate+0x4a5/0x600 >> [<ffffffff8123d5b8>] ? journal_start+0xb8/0x100 >> [<ffffffff8106f406>] ? bit_waitqueue+0x16/0xc0 >> [<ffffffff811d4598>] ext3_evict_inode+0x248/0x2c0 >> [<ffffffff81153b9a>] evict+0xaa/0x1b0 >> [<ffffffff81154843>] iput+0x103/0x210 >> [<ffffffff8114fc88>] dentry_iput+0x88/0xd0 >> [<ffffffff811505ec>] dput+0x12c/0x250 >> [<ffffffff81146275>] path_put+0x15/0x30 >> [<ffffffff810b2f35>] __audit_syscall_exit+0x2e5/0x460 >> [<ffffffff816b30be>] sysexit_audit+0x29/0x5b >> Code: 04 00 00 4c 8d 88 c0 02 00 00 31 c0 e8 5f da ff ff 48 85 db 74 >> 0c 80 43 5c 01 48 89 df e8 d5 >> 6a aa ff 5b 41 5c 5d c3 55 48 89 e5 <0f> 0b 55 48 89 e5 0f 0b 55 48 89 >> e5 0f 0b 55 48 89 e5 41 54 53 >> RIP [<ffffffff816a99f4>] check_irqs_on.part.8+0x4/0x6 >> RSP <ffff8807b156dc28> >> ---[ end trace 8d09f8cfbb601c14 ]--- >> >> > > I don't see a function called sysexit_audit in 3.5. I assume that's > created via some sort of macro goop? It looks like it's defined in arch/x86/kernel/entry_32.S my asm is non-existent, but it looks like it's calling __audit_syscall_exit and the disabling interrupts.

From what I can tell though, it looks like it should be calling