| Message ID | 20220226155851.4176109-1-trix@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/amdgpu: Fix realloc of ptr | expand |
From: trix@redhat.com > Sent: 26 February 2022 15:59 > > From: Tom Rix <trix@redhat.com> > > Clang static analysis reports this error > amdgpu_debugfs.c:1690:9: warning: 1st function call > argument is an uninitialized value > tmp = krealloc_array(tmp, i + 1, > ^~~~~~~~~~~~~~~~~~~~~~~~~~~ > > realloc will free tmp, so tmp can not be garbage. > And the return needs to be checked. Are you sure? A quick check seems to show that krealloc() behaves the same way as libc realloc() and the pointer isn't freed on failure. David > Fixes: 5ce5a584cb82 ("drm/amdgpu: add debugfs for reset registers list") > Signed-off-by: Tom Rix <trix@redhat.com> > --- > drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c > index 9eb9b440bd438..159b97c0b4ebc 100644 > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c > @@ -1676,7 +1676,7 @@ static ssize_t amdgpu_reset_dump_register_list_write(struct file *f, > { > struct amdgpu_device *adev = (struct amdgpu_device *)file_inode(f)->i_private; > char reg_offset[11]; > - uint32_t *tmp; > + uint32_t *tmp = NULL; > int ret, i = 0, len = 0; > > do { > @@ -1688,6 +1688,10 @@ static ssize_t amdgpu_reset_dump_register_list_write(struct file *f, > } > > tmp = krealloc_array(tmp, i + 1, sizeof(uint32_t), GFP_KERNEL); > + if (!tmp) { > + ret = -ENOMEM; > + goto error_free; > + } > if (sscanf(reg_offset, "%X %n", &tmp[i], &ret) != 1) { > ret = -EINVAL; > goto error_free; > -- > 2.26.3 - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
On 2/26/22 2:21 PM, David Laight wrote: > From: trix@redhat.com >> Sent: 26 February 2022 15:59 >> >> From: Tom Rix <trix@redhat.com> >> >> Clang static analysis reports this error >> amdgpu_debugfs.c:1690:9: warning: 1st function call >> argument is an uninitialized value >> tmp = krealloc_array(tmp, i + 1, >> ^~~~~~~~~~~~~~~~~~~~~~~~~~~ >> >> realloc will free tmp, so tmp can not be garbage. >> And the return needs to be checked. > Are you sure? > A quick check seems to show that krealloc() behaves the same > way as libc realloc() and the pointer isn't freed on failure. I suck, I'll respin the patch Thanks Tom > > David > >> Fixes: 5ce5a584cb82 ("drm/amdgpu: add debugfs for reset registers list") >> Signed-off-by: Tom Rix <trix@redhat.com> >> --- >> drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c | 6 +++++- >> 1 file changed, 5 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c >> index 9eb9b440bd438..159b97c0b4ebc 100644 >> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c >> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c >> @@ -1676,7 +1676,7 @@ static ssize_t amdgpu_reset_dump_register_list_write(struct file *f, >> { >> struct amdgpu_device *adev = (struct amdgpu_device *)file_inode(f)->i_private; >> char reg_offset[11]; >> - uint32_t *tmp; >> + uint32_t *tmp = NULL; >> int ret, i = 0, len = 0; >> >> do { >> @@ -1688,6 +1688,10 @@ static ssize_t amdgpu_reset_dump_register_list_write(struct file *f, >> } >> >> tmp = krealloc_array(tmp, i + 1, sizeof(uint32_t), GFP_KERNEL); >> + if (!tmp) { >> + ret = -ENOMEM; >> + goto error_free; >> + } >> if (sscanf(reg_offset, "%X %n", &tmp[i], &ret) != 1) { >> ret = -EINVAL; >> goto error_free; >> -- >> 2.26.3 > - > Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK > Registration No: 1397386 (Wales) >
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c index 9eb9b440bd438..159b97c0b4ebc 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c @@ -1676,7 +1676,7 @@ static ssize_t amdgpu_reset_dump_register_list_write(struct file *f, { struct amdgpu_device *adev = (struct amdgpu_device *)file_inode(f)->i_private; char reg_offset[11]; - uint32_t *tmp; + uint32_t *tmp = NULL; int ret, i = 0, len = 0; do { @@ -1688,6 +1688,10 @@ static ssize_t amdgpu_reset_dump_register_list_write(struct file *f, } tmp = krealloc_array(tmp, i + 1, sizeof(uint32_t), GFP_KERNEL); + if (!tmp) { + ret = -ENOMEM; + goto error_free; + } if (sscanf(reg_offset, "%X %n", &tmp[i], &ret) != 1) { ret = -EINVAL; goto error_free;