linux.git/drivers/video/fbdev, branch v5.4.142

fbmem: Do not delete the mode that is still in use

2021-07-20T14:10:40+00:00

commit 0af778269a522c988ef0b4188556aba97fb420cc upstream.

The execution of fb_delete_videomode() is not based on the result of the
previous fbcon_mode_deleted(). As a result, the mode is directly deleted,
regardless of whether it is still in use, which may cause UAF.

==================================================================
BUG: KASAN: use-after-free in fb_mode_is_equal+0x36e/0x5e0 \
drivers/video/fbdev/core/modedb.c:924
Read of size 4 at addr ffff88807e0ddb1c by task syz-executor.0/18962

CPU: 2 PID: 18962 Comm: syz-executor.0 Not tainted 5.10.45-rc1+ #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ...
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x137/0x1be lib/dump_stack.c:118
 print_address_description+0x6c/0x640 mm/kasan/report.c:385
 __kasan_report mm/kasan/report.c:545 [inline]
 kasan_report+0x13d/0x1e0 mm/kasan/report.c:562
 fb_mode_is_equal+0x36e/0x5e0 drivers/video/fbdev/core/modedb.c:924
 fbcon_mode_deleted+0x16a/0x220 drivers/video/fbdev/core/fbcon.c:2746
 fb_set_var+0x1e1/0xdb0 drivers/video/fbdev/core/fbmem.c:975
 do_fb_ioctl+0x4d9/0x6e0 drivers/video/fbdev/core/fbmem.c:1108
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:739
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 18960:
 kasan_save_stack mm/kasan/common.c:48 [inline]
 kasan_set_track+0x3d/0x70 mm/kasan/common.c:56
 kasan_set_free_info+0x17/0x30 mm/kasan/generic.c:355
 __kasan_slab_free+0x108/0x140 mm/kasan/common.c:422
 slab_free_hook mm/slub.c:1541 [inline]
 slab_free_freelist_hook+0xd6/0x1a0 mm/slub.c:1574
 slab_free mm/slub.c:3139 [inline]
 kfree+0xca/0x3d0 mm/slub.c:4121
 fb_delete_videomode+0x56a/0x820 drivers/video/fbdev/core/modedb.c:1104
 fb_set_var+0x1f3/0xdb0 drivers/video/fbdev/core/fbmem.c:978
 do_fb_ioctl+0x4d9/0x6e0 drivers/video/fbdev/core/fbmem.c:1108
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:739
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: 13ff178ccd6d ("fbcon: Call fbcon_mode_deleted/new_modelist directly")
Signed-off-by: Zhen Lei 
Cc:  # v5.3+
Signed-off-by: Daniel Vetter 
Link: https://patchwork.freedesktop.org/patch/msgid/20210712085544.2828-1-thunder.leizhen@huawei.com
Signed-off-by: Greg Kroah-Hartman

video: fbdev: imxfb: Fix an error message

2021-07-14T14:53:26+00:00

[ Upstream commit 767d724a160eb1cd00c86fb8c2e21fa1ab3c37ac ]

'ret' is known to be 0 here.
No error code is available, so just remove it from the error message.

Fixes: 72330b0eeefc ("i.MX Framebuffer: Use readl/writel instead of direct pointer deref")
Reviewed-by: Uwe Kleine-König 
Signed-off-by: Christophe JAILLET 
Signed-off-by: Daniel Vetter 
Link: https://patchwork.freedesktop.org/patch/msgid/d7b25026f82659da3c6f7159eea480faa9d738be.1620327302.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Sasha Levin

video: hgafb: correctly handle card detect failure during probe

2021-05-26T10:05:21+00:00

commit 02625c965239b71869326dd0461615f27307ecb3 upstream.

The return value of hga_card_detect() is not properly handled causing
the probe to succeed even though hga_card_detect() failed. Since probe
succeeds, hgafb_open() can be called which will end up operating on an
unmapped hga_vram. This results in an out-of-bounds access as reported
by kernel test robot [1].

To fix this, correctly detect failure of hga_card_detect() by checking
for a non-zero error code.

[1]: https://lore.kernel.org/lkml/20210516150019.GB25903@xsang-OptiPlex-9020/

Fixes: dc13cac4862c ("video: hgafb: fix potential NULL pointer dereference")
Cc: stable 
Reported-by: kernel test robot 
Reviewed-by: Igor Matheus Andrade Torrente 
Signed-off-by: Anirudh Rayabharam 
Signed-off-by: Dan Carpenter 
Link: https://lore.kernel.org/r/20210516192714.25823-1-mail@anirudhrb.com
Signed-off-by: Greg Kroah-Hartman

tty: vt: always invoke vc->vc_sw->con_resize callback

2021-05-26T10:05:20+00:00

commit ffb324e6f874121f7dce5bdae5e05d02baae7269 upstream.

syzbot is reporting OOB write at vga16fb_imageblit() [1], for
resize_screen() from ioctl(VT_RESIZE) returns 0 without checking whether
requested rows/columns fit the amount of memory reserved for the graphical
screen if current mode is KD_GRAPHICS.

----------
  #include 
  #include 
  #include 
  #include 
  #include 
  #include 

  int main(int argc, char *argv[])
  {
        const int fd = open("/dev/char/4:1", O_RDWR);
        struct vt_sizes vt = { 0x4100, 2 };

        ioctl(fd, KDSETMODE, KD_GRAPHICS);
        ioctl(fd, VT_RESIZE, &vt);
        ioctl(fd, KDSETMODE, KD_TEXT);
        return 0;
  }
----------

Allow framebuffer drivers to return -EINVAL, by moving vc->vc_mode !=
KD_GRAPHICS check from resize_screen() to fbcon_resize().

Link: https://syzkaller.appspot.com/bug?extid=1f29e126cf461c4de3b3 [1]
Reported-by: syzbot 
Suggested-by: Linus Torvalds 
Signed-off-by: Tetsuo Handa 
Tested-by: syzbot 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

video: hgafb: fix potential NULL pointer dereference

2021-05-26T10:05:20+00:00

commit dc13cac4862cc68ec74348a80b6942532b7735fa upstream.

The return of ioremap if not checked, and can lead to a NULL to be
assigned to hga_vram. Potentially leading to a NULL pointer
dereference.

The fix adds code to deal with this case in the error label and
changes how the hgafb_probe handles the return of hga_card_detect.

Cc: Ferenc Bakonyi 
Cc: Bartlomiej Zolnierkiewicz 
Cc: stable 
Signed-off-by: Igor Matheus Andrade Torrente 
Link: https://lore.kernel.org/r/20210503115736.2104747-40-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman

Revert "video: imsttfb: fix potential NULL pointer dereferences"

2021-05-26T10:05:18+00:00

commit ed04fe8a0e87d7b5ea17d47f4ac9ec962b24814a upstream.

This reverts commit 1d84353d205a953e2381044953b7fa31c8c9702d.

Because of recent interactions with developers from @umn.edu, all
commits from them have been recently re-reviewed to ensure if they were
correct or not.

Upon review, this commit was found to be incorrect for the reasons
below, so it must be reverted.  It will be fixed up "correctly" in a
later kernel change.

The original commit here, while technically correct, did not fully
handle all of the reported issues that the commit stated it was fixing,
so revert it until it can be "fixed" fully.

Note, ioremap() probably will never fail for old hardware like this, and
if anyone actually used this hardware (a PowerMac era PCI display card),
they would not be using fbdev anymore.

Cc: Kangjie Lu 
Cc: Aditya Pakki 
Cc: Finn Thain 
Cc: Bartlomiej Zolnierkiewicz 
Reviewed-by: Rob Herring 
Fixes: 1d84353d205a ("video: imsttfb: fix potential NULL pointer dereferences")
Cc: stable 
Link: https://lore.kernel.org/r/20210503115736.2104747-67-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman

Revert "video: hgafb: fix potential NULL pointer dereference"

2021-05-26T10:05:18+00:00

commit 58c0cc2d90f1e37c4eb63ae7f164c83830833f78 upstream.

This reverts commit ec7f6aad57ad29e4e66cc2e18e1e1599ddb02542.

Because of recent interactions with developers from @umn.edu, all
commits from them have been recently re-reviewed to ensure if they were
correct or not.

Upon review, this commit was found to be incorrect for the reasons
below, so it must be reverted.  It will be fixed up "correctly" in a
later kernel change.

This patch "looks" correct, but the driver keeps on running and will
fail horribly right afterward if this error condition ever trips.

So points for trying to resolve an issue, but a huge NEGATIVE value for
providing a "fake" fix for the problem as nothing actually got resolved
at all.  I'll go fix this up properly...

Cc: Kangjie Lu 
Cc: Aditya Pakki 
Cc: Ferenc Bakonyi 
Cc: Bartlomiej Zolnierkiewicz 
Fixes: ec7f6aad57ad ("video: hgafb: fix potential NULL pointer dereference")
Cc: stable 
Link: https://lore.kernel.org/r/20210503115736.2104747-39-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman

fbdev: zero-fill colormap in fbcmap.c

2021-05-11T12:04:04+00:00

commit 19ab233989d0f7ab1de19a036e247afa4a0a1e9c upstream.

Use kzalloc() rather than kmalloc() for the dynamically allocated parts
of the colormap in fb_alloc_cmap_gfp, to prevent a leak of random kernel
data to userspace under certain circumstances.

Fixes a KMSAN-found infoleak bug reported by syzbot at:
https://syzkaller.appspot.com/bug?id=741578659feabd108ad9e06696f0c1f2e69c4b6e

Reported-by: syzbot+47fa9c9c648b765305b9@syzkaller.appspotmail.com
Cc: stable 
Reviewed-by: Geert Uytterhoeven 
Signed-off-by: Phillip Potter 
Link: https://lore.kernel.org/r/20210331220719.1499743-1-phil@philpotter.co.uk
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Greg Kroah-Hartman

drivers: video: fbcon: fix NULL dereference in fbcon_cursor()

2021-04-07T12:47:44+00:00

commit 01faae5193d6190b7b3aa93dae43f514e866d652 upstream.

add null-check on function pointer before dereference on ops->cursor

Reported-by: syzbot+b67aaae8d3a927f68d20@syzkaller.appspotmail.com
Cc: stable 
Signed-off-by: Du Cheng 
Link: https://lore.kernel.org/r/20210312081421.452405-1-ducheng2@gmail.com
Signed-off-by: Greg Kroah-Hartman

udlfb: Fix memory leak in dlfb_usb_probe

2021-03-07T11:20:42+00:00

commit 5c0e4110f751934e748a66887c61f8e73805f0f9 upstream.

The dlfb_alloc_urb_list function is called in dlfb_usb_probe function,
after that if an error occurs, the dlfb_free_urb_list function need to
be called.

BUG: memory leak
unreferenced object 0xffff88810adde100 (size 32):
  comm "kworker/1:0", pid 17, jiffies 4294947788 (age 19.520s)
  hex dump (first 32 bytes):
    10 30 c3 0d 81 88 ff ff c0 fa 63 12 81 88 ff ff  .0........c.....
    00 30 c3 0d 81 88 ff ff 80 d1 3a 08 81 88 ff ff  .0........:.....
  backtrace:
    [<0000000019512953>] kmalloc include/linux/slab.h:552 [inline]
    [<0000000019512953>] kzalloc include/linux/slab.h:664 [inline]
    [<0000000019512953>] dlfb_alloc_urb_list drivers/video/fbdev/udlfb.c:1892 [inline]
    [<0000000019512953>] dlfb_usb_probe.cold+0x289/0x988 drivers/video/fbdev/udlfb.c:1704
    [<0000000072160152>] usb_probe_interface+0x177/0x370 drivers/usb/core/driver.c:396
    [<00000000a8d6726f>] really_probe+0x159/0x480 drivers/base/dd.c:554
    [<00000000c3ce4b0e>] driver_probe_device+0x84/0x100 drivers/base/dd.c:738
    [<00000000e942e01c>] __device_attach_driver+0xee/0x110 drivers/base/dd.c:844
    [<00000000de0a5a5c>] bus_for_each_drv+0xb7/0x100 drivers/base/bus.c:431
    [<00000000463fbcb4>] __device_attach+0x122/0x250 drivers/base/dd.c:912
    [<00000000b881a711>] bus_probe_device+0xc6/0xe0 drivers/base/bus.c:491
    [<00000000364bbda5>] device_add+0x5ac/0xc30 drivers/base/core.c:2936
    [<00000000eecca418>] usb_set_configuration+0x9de/0xb90 drivers/usb/core/message.c:2159
    [<00000000edfeca2d>] usb_generic_driver_probe+0x8c/0xc0 drivers/usb/core/generic.c:238
    [<000000001830872b>] usb_probe_device+0x5c/0x140 drivers/usb/core/driver.c:293
    [<00000000a8d6726f>] really_probe+0x159/0x480 drivers/base/dd.c:554
    [<00000000c3ce4b0e>] driver_probe_device+0x84/0x100 drivers/base/dd.c:738
    [<00000000e942e01c>] __device_attach_driver+0xee/0x110 drivers/base/dd.c:844
    [<00000000de0a5a5c>] bus_for_each_drv+0xb7/0x100 drivers/base/bus.c:431

Reported-by: syzbot+c9e365d7f450e8aa615d@syzkaller.appspotmail.com
Signed-off-by: Zqiang 
Signed-off-by: Daniel Vetter 
Link: https://patchwork.freedesktop.org/patch/msgid/20201215063022.16746-1-qiang.zhang@windriver.com
Signed-off-by: Greg Kroah-Hartman