kernel/git/stable/linux.git/drivers/video/fbdev, branch linux-5.12.y

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

2021-07-20T14:02:01+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

2021-07-14T14:59:44+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

2021-05-26T10:59:14+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

2021-05-26T10:59:14+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

2021-05-26T10:59:13+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"

2021-05-26T10:59:11+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"

2021-05-26T10:59:11+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

2021-05-12T06:39:33+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

Merge tag 'hyperv-fixes-signed-20210402' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux

2021-04-03T17:42:20+00:00

Pull Hyper-V fixes from Wei Liu: "One fix from Lu Yunlong for a double free in hvfb_probe" * tag 'hyperv-fixes-signed-20210402' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: video: hyperv_fb: Fix a double free in hvfb_probe

video: hyperv_fb: Fix a double free in hvfb_probe

2021-03-25T13:31:20+00:00

Function hvfb_probe() calls hvfb_getmem(), expecting upon return that info->apertures is either NULL or points to memory that should be freed by framebuffer_release(). But hvfb_getmem() is freeing the memory and leaving the pointer non-NULL, resulting in a double free if an error occurs or later if hvfb_remove() is called. Fix this by removing all kfree(info->apertures) calls in hvfb_getmem(). This will allow framebuffer_release() to free the memory, which follows the pattern of other fbdev drivers. Fixes: 3a6fb6c4255c ("video: hyperv: hyperv_fb: Use physical memory for fb on HyperV Gen 1 VMs.") Signed-off-by: Lv Yunlong Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/20210324103724.4189-1-lyl2019@mail.ustc.edu.cn Signed-off-by: Wei Liu