From: trix@redhat.com
To: thomas@winischhofer.net, b.zolnierkie@samsung.com, akpm@osdl.org
Cc: dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org,
linux-kernel@vger.kernel.org, Tom Rix <trix@redhat.com>
Subject: [PATCH] video: fbdev: sis: fix null ptr dereference
Date: Wed, 5 Aug 2020 07:52:08 -0700 [thread overview]
Message-ID: <20200805145208.17727-1-trix@redhat.com> (raw)
From: Tom Rix <trix@redhat.com>
Clang static analysis reports this representative error
init.c:2501:18: warning: Array access (from variable 'queuedata') results
in a null pointer dereference
templ |= ((queuedata[i] & 0xc0) << 3);
This is the problem block of code
if(ModeNo > 0x13) {
...
if(SiS_Pr->ChipType == SIS_730) {
queuedata = &FQBQData730[0];
} else {
queuedata = &FQBQData[0];
}
} else {
}
queuedata is not set in the else block
Reviewing the old code, the arrays FQBQData730 and FQBQData were
used directly.
So hoist the setting of queuedata out of the if-else block.
Fixes: 544393fe584d ("[PATCH] sisfb update")
Signed-off-by: Tom Rix <trix@redhat.com>
---
drivers/video/fbdev/sis/init.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/drivers/video/fbdev/sis/init.c b/drivers/video/fbdev/sis/init.c
index dfe3eb769638..fde27feae5d0 100644
--- a/drivers/video/fbdev/sis/init.c
+++ b/drivers/video/fbdev/sis/init.c
@@ -2428,6 +2428,11 @@ SiS_SetCRT1FIFO_630(struct SiS_Private *SiS_Pr, unsigned short ModeNo,
i = 0;
+ if (SiS_Pr->ChipType == SIS_730)
+ queuedata = &FQBQData730[0];
+ else
+ queuedata = &FQBQData[0];
+
if(ModeNo > 0x13) {
/* Get VCLK */
@@ -2445,12 +2450,6 @@ SiS_SetCRT1FIFO_630(struct SiS_Private *SiS_Pr, unsigned short ModeNo,
/* Get half colordepth */
colorth = colortharray[(SiS_Pr->SiS_ModeType - ModeEGA)];
- if(SiS_Pr->ChipType == SIS_730) {
- queuedata = &FQBQData730[0];
- } else {
- queuedata = &FQBQData[0];
- }
-
do {
templ = SiS_CalcDelay2(SiS_Pr, queuedata[i]) * VCLK * colorth;
--
2.18.1
next reply other threads:[~2020-08-05 17:12 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20200805145226eucas1p1e0e6d9fa3c05f7e247365f0db17cbe38@eucas1p1.samsung.com>
2020-08-05 14:52 ` trix [this message]
2020-09-08 11:37 ` [PATCH] video: fbdev: sis: fix null ptr dereference Bartlomiej Zolnierkiewicz
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