drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dspp.c:31 dpu_setup_dspp_pcc() warn: variable dereferenced before check 'ctx' (see line 29)

From: Dan Carpenter
Date: Mon Mar 01 2021 - 02:01:46 EST


tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: fe07bfda2fb9cdef8a4d4008a409bb02f35f1bd8
commit: 4259ff7ae509ed880b3a7bb685972c3a3bf4b74b drm/msm/dpu: add support for pcc color block in dpu driver
config: arm64-randconfig-m031-20210301 (attached as .config)
compiler: aarch64-linux-gcc (GCC) 9.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

smatch warnings:
drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dspp.c:31 dpu_setup_dspp_pcc() warn: variable dereferenced before check 'ctx' (see line 29)

vim +/ctx +31 drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dspp.c

4259ff7ae509ed Kalyan Thota 2020-03-24 28
4259ff7ae509ed Kalyan Thota 2020-03-24 @29 u32 base = ctx->cap->sblk->pcc.base;
^^^^^
Dereference

4259ff7ae509ed Kalyan Thota 2020-03-24 30
4259ff7ae509ed Kalyan Thota 2020-03-24 @31 if (!ctx || !base) {
^^^^
Checked too late

4259ff7ae509ed Kalyan Thota 2020-03-24 32 DRM_ERROR("invalid ctx %pK pcc base 0x%x\n", ctx, base);
4259ff7ae509ed Kalyan Thota 2020-03-24 33 return;
4259ff7ae509ed Kalyan Thota 2020-03-24 34 }

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Attachment: .config.gz
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