kernel/linux.git/drivers/video, branch v4.4.235

fbcon: prevent user font height or width change from causing potential out-of-bounds access

2020-09-03T09:19:26+00:00

commit 39b3cffb8cf3111738ea993e2757ab382253d86a upstream. Add a check to fbcon_resize() to ensure that a possible change to user font height or user font width will not allow a font data out-of-bounds access. NOTE: must use original charcount in calculation as font charcount can change and cannot be used to determine the font data allocated size. Signed-off-by: George Kennedy Cc: stable Reported-by: syzbot+38a3699c7eaf165b97a6@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/1596213192-6635-1-git-send-email-george.kennedy@oracle.com Signed-off-by: Greg Kroah-Hartman

omapfb: dss: Fix max fclk divider for omap36xx

2020-08-26T08:27:10+00:00

There appears to be a timing issue where using a divider of 32 breaks the DSS for OMAP36xx despite the TRM stating 32 is a valid number. Through experimentation, it appears that 31 works. This same fix was issued for kernels 4.5+. However, between kernels 4.4 and 4.5, the directory structure was changed when the dss directory was moved inside the omapfb directory. That broke the patch on kernels older than 4.5, because it didn't permit the patch to apply cleanly for 4.4 and older. A similar patch was applied to the 3.16 kernel already, but not to 4.4. Commit 4b911101a5cd ("drm/omap: fix max fclk divider for omap36xx") is on the 3.16 stable branch with notes from Ben about the path change. Since this was applied for 3.16 already, this patch is for kernels 3.17 through 4.4 only. Fixes: f7018c213502 ("video: move fbdev to drivers/video/fbdev") Cc: #3.17 - 4.4 CC: Signed-off-by: Adam Ford Signed-off-by: Greg Kroah-Hartman

console: newport_con: fix an issue about leak related system resources

2020-08-21T08:53:00+00:00

[ Upstream commit fd4b8243877250c05bb24af7fea5567110c9720b ] A call of the function do_take_over_console() can fail here. The corresponding system resources were not released then. Thus add a call of iounmap() and release_mem_region() together with the check of a failure predicate. and also add release_mem_region() on device removal. Fixes: e86bb8acc0fdc ("[PATCH] VT binding: Make newport_con support binding") Suggested-by: Bartlomiej Zolnierkiewicz Signed-off-by: Dejin Zheng Reviewed-by: Andy Shevchenko Cc: Greg Kroah-Hartman cc: Thomas Gleixner Cc: Andrew Morton Signed-off-by: Bartlomiej Zolnierkiewicz Link: https://patchwork.freedesktop.org/patch/msgid/20200423164251.3349-1-zhengdejin5@gmail.com Signed-off-by: Sasha Levin

video: fbdev: sm712fb: fix an issue about iounmap for a wrong address

2020-08-21T08:53:00+00:00

[ Upstream commit 98bd4f72988646c35569e1e838c0ab80d06c77f6 ] the sfb->fb->screen_base is not save the value get by iounmap() when the chip id is 0x720. so iounmap() for address sfb->fb->screen_base is not right. Fixes: 1461d6672864854 ("staging: sm7xxfb: merge sm712fb with fbdev") Cc: Andy Shevchenko Cc: Sudip Mukherjee Cc: Teddy Wang Cc: Greg Kroah-Hartman Signed-off-by: Dejin Zheng Signed-off-by: Bartlomiej Zolnierkiewicz Link: https://patchwork.freedesktop.org/patch/msgid/20200422160719.27763-1-zhengdejin5@gmail.com Signed-off-by: Sasha Levin

video: fbdev: neofb: fix memory leak in neo_scan_monitor()

2020-08-21T08:52:58+00:00

[ Upstream commit edcb3895a751c762a18d25c8d9846ce9759ed7e1 ] neofb_probe() calls neo_scan_monitor() that can successfully allocate a memory for info->monspecs.modedb and proceed to case 0x03. There it does not free the memory and returns -1. neofb_probe() goes to label err_scan_monitor, thus, it does not free this memory through calling fb_destroy_modedb() as well. We can not go to label err_init_hw since neo_scan_monitor() can fail during memory allocation. So, the patch frees the memory directly for case 0x03. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Evgeny Novikov Cc: Jani Nikula Cc: Mike Rapoport Cc: Daniel Vetter Cc: Andrew Morton Signed-off-by: Bartlomiej Zolnierkiewicz Link: https://patchwork.freedesktop.org/patch/msgid/20200630195451.18675-1-novikov@ispras.ru Signed-off-by: Sasha Levin

vgacon: Fix for missing check in scrollback handling

2020-08-21T08:52:55+00:00

commit ebfdfeeae8c01fcb2b3b74ffaf03876e20835d2d upstream. vgacon_scrollback_update() always leaves enbough room in the scrollback buffer for the next call, but if the console size changed that room might not actually be enough, and so we need to re-check. The check should be in the loop since vgacon_scrollback_cur->tail is updated in the loop and count may be more than 1 when triggered by CSI M, as Jiri's PoC: #include #include #include #include #include #include #include int main(int argc, char** argv) { int fd = open("/dev/tty1", O_RDWR); unsigned short size[3] = {25, 200, 0}; ioctl(fd, 0x5609, size); // VT_RESIZE write(fd, "\e[1;1H", 6); for (int i = 0; i < 30; i++) write(fd, "\e[10M", 5); } It leads to various crashes as vgacon_scrollback_update writes out of the buffer: BUG: unable to handle page fault for address: ffffc900001752a0 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page RIP: 0010:mutex_unlock+0x13/0x30 ... Call Trace: n_tty_write+0x1a0/0x4d0 tty_write+0x1a0/0x2e0 Or to KASAN reports: BUG: KASAN: slab-out-of-bounds in vgacon_scroll+0x57a/0x8ed This fixes CVE-2020-14331. Reported-by: 张云海 Reported-by: Yang Yingliang Reported-by: Kyungtae Kim Fixes: 15bdab959c9b ([PATCH] vgacon: Add support for soft scrollback) Cc: stable@vger.kernel.org Cc: linux-fbdev@vger.kernel.org Cc: Linus Torvalds Cc: Solar Designer Cc: "Srivatsa S. Bhat" Cc: Anthony Liguori Cc: Yang Yingliang Cc: Bartlomiej Zolnierkiewicz Cc: Jiri Slaby Signed-off-by: Yunhai Zhang Link: https://lore.kernel.org/r/9fb43895-ca91-9b07-ebfd-808cf854ca95@nsfocus.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman

fbdev: Detect integer underflow at "struct fbcon_ops"->clear_margins.

2020-08-21T08:52:53+00:00

[ Upstream commit 033724d6864245a11f8e04c066002e6ad22b3fd0 ] syzbot is reporting general protection fault in bitfill_aligned() [1] caused by integer underflow in bit_clear_margins(). The cause of this problem is when and how do_vc_resize() updates vc->vc_{cols,rows}. If vc_do_resize() fails (e.g. kzalloc() fails) when var.xres or var.yres is going to shrink, vc->vc_{cols,rows} will not be updated. This allows bit_clear_margins() to see info->var.xres < (vc->vc_cols * cw) or info->var.yres < (vc->vc_rows * ch). Unexpectedly large rw or bh will try to overrun the __iomem region and causes general protection fault. Also, vc_resize(vc, 0, 0) does not set vc->vc_{cols,rows} = 0 due to new_cols = (cols ? cols : vc->vc_cols); new_rows = (lines ? lines : vc->vc_rows); exception. Since cols and lines are calculated as cols = FBCON_SWAP(ops->rotate, info->var.xres, info->var.yres); rows = FBCON_SWAP(ops->rotate, info->var.yres, info->var.xres); cols /= vc->vc_font.width; rows /= vc->vc_font.height; vc_resize(vc, cols, rows); in fbcon_modechanged(), var.xres < vc->vc_font.width makes cols = 0 and var.yres < vc->vc_font.height makes rows = 0. This means that const int fd = open("/dev/fb0", O_ACCMODE); struct fb_var_screeninfo var = { }; ioctl(fd, FBIOGET_VSCREENINFO, &var); var.xres = var.yres = 1; ioctl(fd, FBIOPUT_VSCREENINFO, &var); easily reproduces integer underflow bug explained above. Of course, callers of vc_resize() are not handling vc_do_resize() failure is bad. But we can't avoid vc_resize(vc, 0, 0) which returns 0. Therefore, as a band-aid workaround, this patch checks integer underflow in "struct fbcon_ops"->clear_margins call, assuming that vc->vc_cols * vc->vc_font.width and vc->vc_rows * vc->vc_font.heigh do not cause integer overflow. [1] https://syzkaller.appspot.com/bug?id=a565882df74fa76f10d3a6fec4be31098dbb37c6 Reported-and-tested-by: syzbot Signed-off-by: Tetsuo Handa Acked-by: Daniel Vetter Cc: stable Link: https://lore.kernel.org/r/20200715015102.3814-1-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

video: fbdev: w100fb: Fix a potential double free.

2020-06-20T08:23:18+00:00

commit 18722d48a6bb9c2e8d046214c0a5fd19d0a7c9f6 upstream. Some memory is vmalloc'ed in the 'w100fb_save_vidmem' function and freed in the 'w100fb_restore_vidmem' function. (these functions are called respectively from the 'suspend' and the 'resume' functions) However, it is also freed in the 'remove' function. In order to avoid a potential double free, set the corresponding pointer to NULL once freed in the 'w100fb_restore_vidmem' function. Fixes: aac51f09d96a ("[PATCH] w100fb: Rewrite for platform independence") Cc: Richard Purdie Cc: Antonino Daplas Cc: Bartlomiej Zolnierkiewicz Cc: # v2.6.14+ Signed-off-by: Christophe JAILLET Signed-off-by: Sam Ravnborg Link: https://patchwork.freedesktop.org/patch/msgid/20200506181902.193290-1-christophe.jaillet@wanadoo.fr Signed-off-by: Greg Kroah-Hartman

x86/cpu: Rename cpu_data.x86_mask to cpu_data.x86_stepping

2020-06-11T07:21:40+00:00

commit b399151cb48db30ad1e0e93dd40d68c6d007b637 upstream. x86_mask is a confusing name which is hard to associate with the processor's stepping. Additionally, correct an indent issue in lib/cpu.c. [ Backport by Mark Gross to simplify the SRBDS backport ] Signed-off-by: Jia Zhang [ Updated it to more recent kernels. ] Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: bp@alien8.de Cc: tony.luck@intel.com Link: http://lkml.kernel.org/r/1514771530-70829-1-git-send-email-qianyue.zj@alibaba-inc.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

fbdev: potential information leak in do_fb_ioctl()

2020-04-24T05:57:25+00:00

commit d3d19d6fc5736a798b118971935ce274f7deaa82 upstream. The "fix" struct has a 2 byte hole after ->ywrapstep and the "fix = info->fix;" assignment doesn't necessarily clear it. It depends on the compiler. The solution is just to replace the assignment with an memcpy(). Fixes: 1f5e31d7e55a ("fbmem: don't call copy_from/to_user() with mutex held") Signed-off-by: Dan Carpenter Cc: Andrew Morton Cc: Arnd Bergmann Cc: "Eric W. Biederman" Cc: Andrea Righi Cc: Daniel Vetter Cc: Sam Ravnborg Cc: Maarten Lankhorst Cc: Daniel Thompson Cc: Peter Rosin Cc: Jani Nikula Cc: Gerd Hoffmann Signed-off-by: Bartlomiej Zolnierkiewicz Link: https://patchwork.freedesktop.org/patch/msgid/20200113100132.ixpaymordi24n3av@kili.mountain Signed-off-by: Greg Kroah-Hartman