lkml.org 
[lkml]   [2021]   [Mar]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] zero-fill colormap in drivers/video/fbdev/core/fbcmap.c
Date
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
Signed-off-by: Phillip Potter <phil@philpotter.co.uk>
---
drivers/video/fbdev/core/fbcmap.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/video/fbdev/core/fbcmap.c b/drivers/video/fbdev/core/fbcmap.c
index 757d5c3f620b..ff09e57f3c38 100644
--- a/drivers/video/fbdev/core/fbcmap.c
+++ b/drivers/video/fbdev/core/fbcmap.c
@@ -101,17 +101,17 @@ int fb_alloc_cmap_gfp(struct fb_cmap *cmap, int len, int transp, gfp_t flags)
if (!len)
return 0;

- cmap->red = kmalloc(size, flags);
+ cmap->red = kzalloc(size, flags);
if (!cmap->red)
goto fail;
- cmap->green = kmalloc(size, flags);
+ cmap->green = kzalloc(size, flags);
if (!cmap->green)
goto fail;
- cmap->blue = kmalloc(size, flags);
+ cmap->blue = kzalloc(size, flags);
if (!cmap->blue)
goto fail;
if (transp) {
- cmap->transp = kmalloc(size, flags);
+ cmap->transp = kzalloc(size, flags);
if (!cmap->transp)
goto fail;
} else {
--
2.30.2
\
 
 \ /
  Last update: 2021-04-01 00:09    [W:0.075 / U:1.492 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site