Messages in this thread Patch in this message | | | From | Sven Schnelle <> | Subject | [PATCH] [SCSI] gdth: Allocate sense_buffer to prevent NULL pointer dereference | Date | Sun, 09 Mar 2008 13:41:40 +0100 |
| |
Hi,
i'm facing the following kernel oops with the latest git:
--------------------------------------8<-------------------------------------- Stopping MD arrays...failed (no MD subsystem loaded). Mounting root filesystem read-only...done. Will now restart. BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 IP: [<ffffffff8051a97e>] __gdth_interrupt+0x96e/0xb7f PGD 7e51e067 PUD 7e6a1067 PMD 0 Oops: 0002 [1] PREEMPT SMP CPU 3 Modules linked in: nvidia(P) lm85 hwmon_vid hwmon [last unloaded: nvidia] Pid: 0, comm: swapper Tainted: P 2.6.25-rc4-smp-00134-g84c6f60 #11 RIP: 0010:[<ffffffff8051a97e>] [<ffffffff8051a97e>] __gdth_interrupt+0x96e/0xb7f RSP: 0018:ffff81007fbefed8 EFLAGS: 00010086 RAX: 0000000000000000 RBX: ffff81007e0dda68 RCX: 0000000000000002 RDX: 00000000ffffffff RSI: 0000000000000000 RDI: ffffc20000330000 RBP: ffff81007fbeff08 R08: 0000000000000000 R09: ffff81007f01de70 R10: 0000000000000000 R11: 0000000000000050 R12: ffff810000b10480 R13: ffff810000b104ff R14: ffff81007e214200 R15: 0000000000000009 FS: 0000000000000000(0000) GS:ffff81007f802c80(0000) knlGS:0000000000000000 CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b CR2: 0000000000000000 CR3: 000000007e643000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process swapper (pid: 0, threadinfo ffff81007fbe6000, task ffff81007fbe4000) Stack: 0000000000000046 ffff81007e8a93c0 0000000000000000 0000000000000000 0000000000000018 0000000000000003 ffff81007fbeff18 ffffffff8051ab9f ffff81007fbeff48 ffffffff80258cc2 ffffffff8092e300 ffff81007e8a93c0 Call Trace: <IRQ> [<ffffffff8051ab9f>] gdth_interrupt+0x10/0x12 [<ffffffff80258cc2>] handle_IRQ_event+0x27/0x57 [<ffffffff8025a055>] handle_fasteoi_irq+0x9c/0xdc [<ffffffff8020def0>] do_IRQ+0x88/0xfc [<ffffffff80209ffe>] ? default_idle+0x0/0x5f [<ffffffff8020b851>] ret_from_intr+0x0/0xa <EOI> [<ffffffff8020a037>] ? default_idle+0x39/0x5f [<ffffffff8020a032>] ? default_idle+0x34/0x5f [<ffffffff80209ffe>] ? default_idle+0x0/0x5f [<ffffffff8020a11c>] ? cpu_idle+0xbf/0xf5 [<ffffffff806cd973>] ? start_secondary+0x3e0/0x3ef
Code: 00 04 eb 15 3c 17 75 11 41 0f b6 c5 48 c1 e0 05 41 80 a4 04 92 02 00 00 fb 41 c7 86 18 01 00 00 00 00 00 00 49 8b 86 c0 00 00 00 <c6> 00 00 e9 92 01 00 00 66 89 43 24 41 8b 84 24 68 02 00 00 89 RIP [<ffffffff8051a97e>] __gdth_interrupt+0x96e/0xb7f RSP <ffff81007fbefed8> CR2: 0000000000000000 ---[ end trace e81e561a458e8791 ]--- Kernel panic - not syncing: Aiee, killing interrupt handler! Rebooting in 5 seconds.. --------------------------------------8<--------------------------------------
From 2dc63f9f8e61fd1c89f8b4d9b2d174be1c3bfbe2 Mon Sep 17 00:00:00 2001 From: root <root@apollo.bitebene.org> Date: Sun, 9 Mar 2008 13:25:07 +0100 Subject:
This fixes a NULL pointer dereference during execution of Internal commands, where gdth only allocates scp, but not scp->sense_buffer. The rest of the code assumes that sense_buffer is allocated, which leads to a kernel oops e.g. on reboot (during cache flush).
So we have two choices here:
a) Allocate the sense_buffer b) surrounding all accesses to sense_buffer with some if (!internal_command)
I'm using solution a, as this keeps code simpler.
Signed-off-by: Sven Schnelle <svens@stackframe.org> --- drivers/scsi/gdth.c | 7 +++++++ 1 files changed, 7 insertions(+), 0 deletions(-)
diff --git a/drivers/scsi/gdth.c b/drivers/scsi/gdth.c index 27ebd33..0b2080d 100644 --- a/drivers/scsi/gdth.c +++ b/drivers/scsi/gdth.c @@ -493,6 +493,12 @@ int __gdth_execute(struct scsi_device *sdev, gdth_cmd_str *gdtcmd, char *cmnd, if (!scp) return -ENOMEM; + scp->sense_buffer = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_KERNEL); + if (!scp->sense_buffer) { + kfree(scp); + return -ENOMEM; + } + scp->device = sdev; memset(&cmndinfo, 0, sizeof(cmndinfo)); @@ -513,6 +519,7 @@ int __gdth_execute(struct scsi_device *sdev, gdth_cmd_str *gdtcmd, char *cmnd, rval = cmndinfo.status; if (info) *info = cmndinfo.info; + kfree(scp->sense_buffer); kfree(scp); return rval; } -- 1.5.4.3 Cheers,
Sven. [unhandled content-type:application/pgp-signature] | |