vma_resv_map bug.

Since c50ac050811d6485616a193eb0f37bfbd191cc89, I can trigger this fairly easily using my syscall fuzzer.

Dave

BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
IP: [<ffffffff81182959>] vma_resv_map+0x9/0x30
PGD 141453067 PUD 1421e1067 PMD 0 
Oops: 0000 [#1] PREEMPT SMP 
CPU 6 
Modules linked in: binfmt_misc caif_socket caif phonet bluetooth rfkill can llc2 pppoe pppox ppp_generic slhc irda crc_ccitt rds af_key decnet rose x25 atm netrom appletalk ipx p8023 psnap p8022 llc ax25 ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables kvm_intel kvm crc32c_intel ghash_clmulni_intel microcode serio_raw pcspkr i2c_i801 lpc_ich mfd_core e1000e nfsd nfs_acl auth_rpcgss lockd sunrpc i915 video i2c_algo_bit drm_kms_helper drm i2c_core [last unloaded: scsi_wait_scan]

Pid: 14006, comm: trinity-child6 Not tainted 3.4.0+ #36

RIP: 0010:[<ffffffff81182959>]  [<ffffffff81182959>] vma_resv_map+0x9/0x30
RSP: 0018:ffff8801414e1d48  EFLAGS: 00010246
RAX: 00000000fffffff4 RBX: 0000000000000000 RCX: 000000000000b990
RDX: 00000000fffffff4 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff8801414e1d48 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000002 R12: 0000000000000000
R13: 0000000000000001 R14: 0000000000000001 R15: ffff88013febf0d0
FS:  00007fc3866f5740(0000) GS:ffff880148800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000030 CR3: 00000001437b1000 CR4: 00000000001407e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process trinity-child6 (pid: 14006, threadinfo ffff8801414e0000, task ffff8801414f26b0)
Stack:
 ffff8801414e1d58 ffffffff81182cde ffff8801414e1db8 ffffffff81185fe6
 0000000000008000 00000000fffffff4 ffffffff82a24ce0 0000000000000000
 ffff8801414e1db8 ffff88013febf0d0 0000000000000001 ffff880137b05c20
Call Trace:
 [<ffffffff81182cde>] resv_map_put+0xe/0x40
 [<ffffffff81185fe6>] hugetlb_reserve_pages+0xa6/0x1d0
 [<ffffffff8128c312>] hugetlb_file_setup+0x102/0x2c0
 [<ffffffff812a1a25>] newseg+0x115/0x360
 [<ffffffff8129bcfe>] ipcget+0x1ce/0x310
 [<ffffffff812a1e6a>] sys_shmget+0x5a/0x60
 [<ffffffff812a1910>] ? shmctl_down.constprop.14+0x180/0x180
 [<ffffffff812a0f90>] ? shm_release+0x50/0x50
 [<ffffffff812a0f20>] ? shm_get_unmapped_area+0x20/0x20
 [<ffffffff816613d2>] system_call_fastpath+0x16/0x1b
Code: 40 30 48 8b 40 28 48 8b 80 b0 05 00 00 48 8b 40 58 8b 48 08 b8 01 00 00 00 83 c1 0c 48 d3 e0 c3 66 90 55 48 89 e5 66 66 66 66 90 <48> 8b 47 30 a9 00 00 40 00 74 18 a8 80 75 10 48 8b 87 a0 00 00 

The same error here. Here is my dmesg. Hope it helps.

[  497.674360] trinity-child0 (31412): Using mlock ulimits for SHM_HUGETLB is deprecated
[  502.461866] warning: process `trinity-child0' used the deprecated sysctl system call with 
[  502.576500] BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
[  502.577028] IP: [<ffffffff81135bed>] vma_resv_map+0x9/0x2b
[  502.577028] PGD a012067 PUD a86b067 PMD 0 
[  502.577028] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
[  502.577028] CPU 0 
[  502.577028] Modules linked in:
[  502.577028] 
[  502.577028] Pid: 31442, comm: trinity-child0 Not tainted 3.4.0+ #7 Bochs Bochs
[  502.577028] RIP: 0010:[<ffffffff81135bed>]  [<ffffffff81135bed>] vma_resv_map+0x9/0x2b
[  502.577028] RSP: 0018:ffff88000a80bd58  EFLAGS: 00010246
[  502.577028] RAX: 00000000fffffff4 RBX: 0000000000000000 RCX: 0000007503e4bb9c
[  502.577028] RDX: 000000000002bdc0 RSI: 0000000000000001 RDI: 0000000000000000
[  502.577028] RBP: ffff88000a80bd58 R08: 0000000000000000 R09: 0000000000000000
[  502.577028] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
[  502.577028] R13: 0000000000000001 R14: fffffffffffffff4 R15: ffff88000e3d8498
[  502.577028] FS:  00007feb4db7d700(0000) GS:ffff88000f400000(0000) knlGS:0000000000000000
[  502.577028] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  502.577028] CR2: 0000000000000030 CR3: 0000000006d09000 CR4: 00000000000006f0
[  502.577028] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  502.577028] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[  502.577028] Process trinity-child0 (pid: 31442, threadinfo ffff88000a80a000, task ffff8800055ba2a0)
[  502.577028] Stack:
[  502.577028]  ffff88000a80bd68 ffffffff81135c1d ffff88000a80bdc8 ffffffff811385b0
[  502.577028]  0000000000000000 ffffffff82a96ec0 0000000000000001 0000000000000000
[  502.577028]  ffff88000e3b2520 0000000000001001 ffff88000aa8cec0 ffff88000e3d8498
[  502.577028] Call Trace:
[  502.577028]  [<ffffffff81135c1d>] resv_map_put+0xe/0x28
[  502.577028]  [<ffffffff811385b0>] hugetlb_reserve_pages+0x18c/0x1a5
[  502.577028]  [<ffffffff812355a4>] hugetlb_file_setup+0x181/0x255
[  502.577028]  [<ffffffff813bedc0>] newseg+0xe2/0x25a
[  502.577028]  [<ffffffff813bb1fb>] ? ipcget+0xad/0x1fd
[  502.577028]  [<ffffffff813bb297>] ipcget+0x149/0x1fd
[  502.577028]  [<ffffffff813bf09a>] sys_shmget+0x5a/0x5e
[  502.577028]  [<ffffffff813becde>] ? shm_try_destroy_orphaned+0x72/0x72
[  502.577028]  [<ffffffff813be645>] ? shm_get_unmapped_area+0x20/0x20
[  502.577028]  [<ffffffff813be652>] ? shm_security+0xd/0xd
[  502.577028]  [<ffffffff819cbee9>] system_call_fastpath+0x16/0x1b
[  502.577028] Code: 40 74 02 0f 0b 48 89 f8 66 66 66 90 48 d1 e8 83 e0 1f 83 f8 1c 76 da 83 f8 1d 0f 94 c0 0f b6 c0 5d c3 55 48 89 e5 66 66 66 66 90 <48> 8b 47 30 a9 00 00 40 00 75 02 0f 0b a8 80 75 0d 48 8b 87 a0 
[  502.577028] RIP  [<ffffffff81135bed>] vma_resv_map+0x9/0x2b
[  502.577028]  RSP <ffff88000a80bd58>
[  502.577028] CR2: 0000000000000030
[  502.638645] ---[ end trace 61d67b4c1e7a2c5d ]---

This should be fixed a few days ago by 4523e1458566a0e8ecfaff90f380dd23acc44d27

Dave