Re: [PATCH] video:uvesafb: Fix oops that uvesafb try to execute NX-protected page

[Florian Tobias Schandinat <FlorianSchandinat@gmx.de>]

Hi,

On 03/05/2012 12:52 AM, Wang YanQing wrote:
> On Fri, Mar 02, 2012 at 08:48:50AM +0800, Wang YanQing wrote:
>>
>> Ok! I think I have learned to make thing simple and send to the right people:)

That's right.

>> This patch try to fix the oops below that catched in my machine

This sounds like you didn't test it. I assume you did? So just write
"This patch fixes the oops below"

>>
>> [   81.560602] uvesafb: NVIDIA Corporation, GT216 Board - 0696a290, Chip Rev   , OEM: NVIDIA, VBE v3.0
>> [   81.609384] uvesafb: protected mode interface info at c000:d350
>> [   81.609388] uvesafb: pmi: set display start = c00cd3b3, set palette = c00cd40e
>> [   81.609390] uvesafb: pmi: ports = 3b4 3b5 3ba 3c0 3c1 3c4 3c5 3c6 3c7 3c8 3c9 3cc 3ce 3cf 3d0 3d1 3d2 3d3 3d4 3d5 3da
>> [   81.614558] uvesafb: VBIOS/hardware doesn't support DDC transfers
>> [   81.614562] uvesafb: no monitor limits have been set, default refresh rate will be used
>> [   81.614994] uvesafb: scrolling: ypan using protected mode interface, yres_virtualI15
>> [   81.744147] kernel tried to execute NX-protected page - exploit attempt? (uid: 0)
>> [   81.744153] BUG: unable to handle kernel paging request at c00cd3b3
>> [   81.744159] IP: [<c00cd3b3>] 0xc00cd3b2
>> [   81.744167] *pdpt = 00000000016d6001 *pde = 0000000001c7b067 *pte = 80000000000cd163
>> [   81.744171] Oops: 0011 [#1] SMP
>> [   81.744174] Modules linked in: uvesafb(+) cfbcopyarea cfbimgblt cfbfillrect
>> [   81.744178]
>> [   81.744181] Pid: 3497, comm: modprobe Not tainted 3.3.0-rc4NX+ #71 Acer            Aspire 4741                    /Aspire 4741
>> [   81.744185] EIP: 0060:[<c00cd3b3>] EFLAGS: 00010246 CPU: 0
>> [   81.744187] EIP is at 0xc00cd3b3
>> [   81.744189] EAX: 00004f07 EBX: 00000000 ECX: 00000000 EDX: 00000000
>> [   81.744191] ESI: f763f000 EDI: f763f6e8 EBP: f57f3a0c ESP: f57f3a00
>> [   81.744192]  DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
>> [   81.744195] Process modprobe (pid: 3497, tiõ7f2000 task÷48c600 task.tiõ7f2000)
>> [   81.744196] Stack:
>> [   81.744197]  f82512c5 f759341c 00000000 f57f3a30 c124a9bc 00000001 00000001 000001e0
>> [   81.744202]  f8251280 f763f000 f7593400 00000000 f57f3a40 c12598dd f5c0c000 00000000
>> [   81.744206]  f57f3b10 c1255efe c125a21a 00000006 f763f09c 00000000 c1c6cb60 f7593400
>> [   81.744210] Call Trace:
>> [   81.744215]  [<f82512c5>] ? uvesafb_pan_display+0x45/0x60 [uvesafb]
>> [   81.744222]  [<c124a9bc>] fb_pan_display+0x10c/0x160
>> [   81.744226]  [<f8251280>] ? uvesafb_vbe_find_mode+0x180/0x180 [uvesafb]
>> [   81.744230]  [<c12598dd>] bit_update_start+0x1d/0x50
>> [   81.744232]  [<c1255efe>] fbcon_switch+0x39e/0x550
>> [   81.744235]  [<c125a21a>] ? bit_cursor+0x4ea/0x560
>> [   81.744240]  [<c129b6cb>] redraw_screen+0x12b/0x220
>> [   81.744245]  [<c128843b>] ? tty_do_resize+0x3b/0xc0
>> [   81.744247]  [<c129ef42>] vc_do_resize+0x3d2/0x3e0
>> [   81.744250]  [<c129efb4>] vc_resize+0x14/0x20
>> [   81.744253]  [<c12586bd>] fbcon_init+0x29d/0x500
>> [   81.744255]  [<c12984c4>] ? set_inverse_trans_unicode+0xe4/0x110
>> [   81.744258]  [<c129b378>] visual_init+0xb8/0x150
>> [   81.744261]  [<c129c16c>] bind_con_driver+0x16c/0x360
>> [   81.744264]  [<c129b47e>] ? register_con_driver+0x6e/0x190
>> [   81.744267]  [<c129c3a1>] take_over_console+0x41/0x50
>> [   81.744269]  [<c1257b7a>] fbcon_takeover+0x6a/0xd0
>> [   81.744272]  [<c12594b8>] fbcon_event_notify+0x758/0x790
>> [   81.744277]  [<c10929e2>] notifier_call_chain+0x42/0xb0
>> [   81.744280]  [<c1092d30>] __blocking_notifier_call_chain+0x60/0x90
>> [   81.744283]  [<c1092d7a>] blocking_notifier_call_chain+0x1a/0x20
>> [   81.744285]  [<c124a5a1>] fb_notifier_call_chain+0x11/0x20
>> [   81.744288]  [<c124b759>] register_framebuffer+0x1d9/0x2b0
>> [   81.744293]  [<c1061c73>] ? ioremap_wc+0x33/0x40
>> [   81.744298]  [<f82537c6>] uvesafb_probe+0xaba/0xc40 [uvesafb]
>> [   81.744302]  [<c12bb81f>] platform_drv_probe+0xf/0x20
>> [   81.744306]  [<c12ba558>] driver_probe_device+0x68/0x170
>> [   81.744309]  [<c12ba731>] __device_attach+0x41/0x50
>> [   81.744313]  [<c12b9088>] bus_for_each_drv+0x48/0x70
>> [   81.744316]  [<c12ba7f3>] device_attach+0x83/0xa0
>> [   81.744319]  [<c12ba6f0>] ? __driver_attach+0x90/0x90
>> [   81.744321]  [<c12b991f>] bus_probe_device+0x6f/0x90
>> [   81.744324]  [<c12b8a45>] device_add+0x5e5/0x680
>> [   81.744329]  [<c122a1a3>] ? kvasprintf+0x43/0x60
>> [   81.744332]  [<c121e6e4>] ? kobject_set_name_vargs+0x64/0x70
>> [   81.744335]  [<c121e6e4>] ? kobject_set_name_vargs+0x64/0x70
>> [   81.744339]  [<c12bbe9f>] platform_device_add+0xff/0x1b0
>> [   81.744343]  [<f8252906>] uvesafb_init+0x50/0x9b [uvesafb]
>> [   81.744346]  [<c100111f>] do_one_initcall+0x2f/0x170
>> [   81.744350]  [<f82528b6>] ? uvesafb_is_valid_mode+0x66/0x66 [uvesafb]
>> [   81.744355]  [<c10c6994>] sys_init_module+0xf4/0x1410
>> [   81.744359]  [<c1157fc0>] ? vfsmount_lock_local_unlock_cpu+0x30/0x30
>> [   81.744363]  [<c144cb10>] sysenter_do_call+0x12/0x36
>> [   81.744365] Code: f5 00 00 00 32 f6 66 8b da 66 d1 e3 66 ba d4 03 8a e3 b0 1c 66 ef b0 1e 66 ef 8a e7 b0 1d 66 ef b0 1f 66 ef e8 fa 00 00 00 61 c3 <60> e8 c8 00 00 00 66 8b f3 66 8b da 66 ba d4 03 b0 0c 8a e5 66
>> [   81.744388] EIP: [<c00cd3b3>] 0xc00cd3b3 SS:ESP 0068:f57f3a00
>> [   81.744391] CR2: 00000000c00cd3b3
>> [   81.744393] ---[ end trace 18b2c87c925b54d6 ]---
>>
>> Signed-off-by: Wang YanQing <udknight@gmail.com>
>> ---
>>  drivers/video/uvesafb.c |   12 ++++++++++--
>>  1 file changed, 10 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/video/uvesafb.c b/drivers/video/uvesafb.c
>> index e7f69ef..f9a670d 100644
>> --- a/drivers/video/uvesafb.c
>> +++ b/drivers/video/uvesafb.c
>> @@ -23,6 +23,7 @@
>>  #include <video/uvesafb.h>
>>  #ifdef CONFIG_X86
>>  #include <video/vga.h>
>> +#include <linux/pci.h>
>>  #endif
>>  #ifdef CONFIG_MTRR
>>  #include <asm/mtrr.h>
>> @@ -815,8 +816,15 @@ static int __devinit uvesafb_vbe_init(struct fb_info *info)
>>  	par->pmi_setpal = pmi_setpal;
>>  	par->ypan = ypan;
>>  
>> -	if (par->pmi_setpal || par->ypan)
>> -		uvesafb_vbe_getpmi(task, par);
>> +	if (par->pmi_setpal || par->ypan) {
>> +		if (pcibios_enabled) {
>> +			uvesafb_vbe_getpmi(task, par);
>> +		} else {
>> +			par->pmi_setpal = par->ypan = 0;
>> +			printk(KERN_WARNING "uvesafb: PCI BIOS area is NX."
>> +				"Can't use protected mode interface\n");
>> +		}
>> +	}
>>  #else
>>  	/* The protected mode interface is not available on non-x86. */
>>  	par->pmi_setpal = par->ypan = 0;
>> -- 
>> 1.7.9.2.315.g25a78
> 
> Ok! Can anybody tell me why this patch had been ignored by community?
> I try to find out what's wrong with this patch, but I failed to find it out.
> So any comment is welcome.Thanks

Patch looks okay to me. I will wait a few days to give Michal a chance to
comment on it.


Best regards,

Florian Tobias Schandinat