Userspace can race to free the gobj(robj converted from), robj should not be accessed again after drm_gem_object_put, otherwith it will result in use-after-free.
Signed-off-by: Min Li lm0963hack@gmail.com --- drivers/gpu/drm/radeon/radeon_gem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/radeon/radeon_gem.c b/drivers/gpu/drm/radeon/radeon_gem.c index bdc5af23f005..450c7cbdd28a 100644 --- a/drivers/gpu/drm/radeon/radeon_gem.c +++ b/drivers/gpu/drm/radeon/radeon_gem.c @@ -478,7 +478,7 @@ int radeon_gem_set_domain_ioctl(struct drm_device *dev, void *data,
drm_gem_object_put(gobj); up_read(&rdev->exclusive_lock); - r = radeon_gem_handle_lockup(robj->rdev, r); + r = radeon_gem_handle_lockup(rdev, r); return r; }
Hi Min,
kernel test robot noticed the following build warnings:
[auto build test WARNING on drm-misc/drm-misc-next] [also build test WARNING on linus/master v6.4-rc3 next-20230525] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Min-Li/drm-radeon-fix-race-co... base: git://anongit.freedesktop.org/drm/drm-misc drm-misc-next patch link: https://lore.kernel.org/r/20230526123753.16160-1-lm0963hack%40gmail.com patch subject: [PATCH] drm/radeon: fix race condition UAF in radeon_gem_set_domain_ioctl config: mips-allyesconfig (https://download.01.org/0day-ci/archive/20230527/202305271806.VvOClWyB-lkp@i...) compiler: mips-linux-gcc (GCC) 12.1.0 reproduce (this is a W=1 build): mkdir -p ~/bin wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # https://github.com/intel-lab-lkp/linux/commit/66fb975494d21e80b90235b7d8bf09... git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Min-Li/drm-radeon-fix-race-condition-UAF-in-radeon_gem_set_domain_ioctl/20230527-155623 git checkout 66fb975494d21e80b90235b7d8bf0953990c5c89 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 ~/bin/make.cross W=1 O=build_dir ARCH=mips olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 ~/bin/make.cross W=1 O=build_dir ARCH=mips SHELL=/bin/bash drivers/gpu/
If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot lkp@intel.com | Closes: https://lore.kernel.org/oe-kbuild-all/202305271806.VvOClWyB-lkp@intel.com/
All warnings (new ones prefixed by >>):
drivers/gpu/drm/radeon/radeon_gem.c: In function 'radeon_gem_set_domain_ioctl':
drivers/gpu/drm/radeon/radeon_gem.c:462:27: warning: variable 'robj' set but not used [-Wunused-but-set-variable]
462 | struct radeon_bo *robj; | ^~~~
vim +/robj +462 drivers/gpu/drm/radeon/radeon_gem.c
f72a113a71ab08 Christian König 2014-08-07 453 771fe6b912fca5 Jerome Glisse 2009-06-05 454 int radeon_gem_set_domain_ioctl(struct drm_device *dev, void *data, 771fe6b912fca5 Jerome Glisse 2009-06-05 455 struct drm_file *filp) 771fe6b912fca5 Jerome Glisse 2009-06-05 456 { 771fe6b912fca5 Jerome Glisse 2009-06-05 457 /* transition the BO to a domain - 771fe6b912fca5 Jerome Glisse 2009-06-05 458 * just validate the BO into a certain domain */ dee53e7fb3ee01 Jerome Glisse 2012-07-02 459 struct radeon_device *rdev = dev->dev_private; 771fe6b912fca5 Jerome Glisse 2009-06-05 460 struct drm_radeon_gem_set_domain *args = data; 771fe6b912fca5 Jerome Glisse 2009-06-05 461 struct drm_gem_object *gobj; 4c7886791264f0 Jerome Glisse 2009-11-20 @462 struct radeon_bo *robj; 771fe6b912fca5 Jerome Glisse 2009-06-05 463 int r; 771fe6b912fca5 Jerome Glisse 2009-06-05 464 771fe6b912fca5 Jerome Glisse 2009-06-05 465 /* for now if someone requests domain CPU - 771fe6b912fca5 Jerome Glisse 2009-06-05 466 * just make sure the buffer is finished with */ dee53e7fb3ee01 Jerome Glisse 2012-07-02 467 down_read(&rdev->exclusive_lock); 771fe6b912fca5 Jerome Glisse 2009-06-05 468 771fe6b912fca5 Jerome Glisse 2009-06-05 469 /* just do a BO wait for now */ a8ad0bd84f9860 Chris Wilson 2016-05-09 470 gobj = drm_gem_object_lookup(filp, args->handle); 771fe6b912fca5 Jerome Glisse 2009-06-05 471 if (gobj == NULL) { dee53e7fb3ee01 Jerome Glisse 2012-07-02 472 up_read(&rdev->exclusive_lock); bf79cb914dbfe8 Chris Wilson 2010-08-04 473 return -ENOENT; 771fe6b912fca5 Jerome Glisse 2009-06-05 474 } 7e4d15d90afe46 Daniel Vetter 2011-02-18 475 robj = gem_to_radeon_bo(gobj); 771fe6b912fca5 Jerome Glisse 2009-06-05 476 771fe6b912fca5 Jerome Glisse 2009-06-05 477 r = radeon_gem_set_domain(gobj, args->read_domains, args->write_domain); 771fe6b912fca5 Jerome Glisse 2009-06-05 478 f11fb66ae92193 Emil Velikov 2020-05-15 479 drm_gem_object_put(gobj); dee53e7fb3ee01 Jerome Glisse 2012-07-02 480 up_read(&rdev->exclusive_lock); 66fb975494d21e Min Li 2023-05-26 481 r = radeon_gem_handle_lockup(rdev, r); 771fe6b912fca5 Jerome Glisse 2009-06-05 482 return r; 771fe6b912fca5 Jerome Glisse 2009-06-05 483 } 771fe6b912fca5 Jerome Glisse 2009-06-05 484
Hi Min,
kernel test robot noticed the following build warnings:
[auto build test WARNING on drm-misc/drm-misc-next] [also build test WARNING on linus/master v6.4-rc3 next-20230525] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Min-Li/drm-radeon-fix-race-co... base: git://anongit.freedesktop.org/drm/drm-misc drm-misc-next patch link: https://lore.kernel.org/r/20230526123753.16160-1-lm0963hack%40gmail.com patch subject: [PATCH] drm/radeon: fix race condition UAF in radeon_gem_set_domain_ioctl config: riscv-randconfig-r042-20230526 (https://download.01.org/0day-ci/archive/20230527/202305272311.JHzuoUJZ-lkp@i...) compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project 4faf3aaf28226a4e950c103a14f6fc1d1fdabb1b) reproduce (this is a W=1 build): mkdir -p ~/bin wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install riscv cross compiling tool for clang build # apt-get install binutils-riscv64-linux-gnu # https://github.com/intel-lab-lkp/linux/commit/66fb975494d21e80b90235b7d8bf09... git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Min-Li/drm-radeon-fix-race-condition-UAF-in-radeon_gem_set_domain_ioctl/20230527-155623 git checkout 66fb975494d21e80b90235b7d8bf0953990c5c89 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang ~/bin/make.cross W=1 O=build_dir ARCH=riscv olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang ~/bin/make.cross W=1 O=build_dir ARCH=riscv SHELL=/bin/bash drivers/gpu/drm/radeon/
If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot lkp@intel.com | Closes: https://lore.kernel.org/oe-kbuild-all/202305272311.JHzuoUJZ-lkp@intel.com/
All warnings (new ones prefixed by >>):
drivers/gpu/drm/radeon/radeon_gem.c:462:20: warning: variable 'robj' set but not used [-Wunused-but-set-variable]
struct radeon_bo *robj; ^ 1 warning generated.
vim +/robj +462 drivers/gpu/drm/radeon/radeon_gem.c
f72a113a71ab08 Christian König 2014-08-07 453 771fe6b912fca5 Jerome Glisse 2009-06-05 454 int radeon_gem_set_domain_ioctl(struct drm_device *dev, void *data, 771fe6b912fca5 Jerome Glisse 2009-06-05 455 struct drm_file *filp) 771fe6b912fca5 Jerome Glisse 2009-06-05 456 { 771fe6b912fca5 Jerome Glisse 2009-06-05 457 /* transition the BO to a domain - 771fe6b912fca5 Jerome Glisse 2009-06-05 458 * just validate the BO into a certain domain */ dee53e7fb3ee01 Jerome Glisse 2012-07-02 459 struct radeon_device *rdev = dev->dev_private; 771fe6b912fca5 Jerome Glisse 2009-06-05 460 struct drm_radeon_gem_set_domain *args = data; 771fe6b912fca5 Jerome Glisse 2009-06-05 461 struct drm_gem_object *gobj; 4c7886791264f0 Jerome Glisse 2009-11-20 @462 struct radeon_bo *robj; 771fe6b912fca5 Jerome Glisse 2009-06-05 463 int r; 771fe6b912fca5 Jerome Glisse 2009-06-05 464 771fe6b912fca5 Jerome Glisse 2009-06-05 465 /* for now if someone requests domain CPU - 771fe6b912fca5 Jerome Glisse 2009-06-05 466 * just make sure the buffer is finished with */ dee53e7fb3ee01 Jerome Glisse 2012-07-02 467 down_read(&rdev->exclusive_lock); 771fe6b912fca5 Jerome Glisse 2009-06-05 468 771fe6b912fca5 Jerome Glisse 2009-06-05 469 /* just do a BO wait for now */ a8ad0bd84f9860 Chris Wilson 2016-05-09 470 gobj = drm_gem_object_lookup(filp, args->handle); 771fe6b912fca5 Jerome Glisse 2009-06-05 471 if (gobj == NULL) { dee53e7fb3ee01 Jerome Glisse 2012-07-02 472 up_read(&rdev->exclusive_lock); bf79cb914dbfe8 Chris Wilson 2010-08-04 473 return -ENOENT; 771fe6b912fca5 Jerome Glisse 2009-06-05 474 } 7e4d15d90afe46 Daniel Vetter 2011-02-18 475 robj = gem_to_radeon_bo(gobj); 771fe6b912fca5 Jerome Glisse 2009-06-05 476 771fe6b912fca5 Jerome Glisse 2009-06-05 477 r = radeon_gem_set_domain(gobj, args->read_domains, args->write_domain); 771fe6b912fca5 Jerome Glisse 2009-06-05 478 f11fb66ae92193 Emil Velikov 2020-05-15 479 drm_gem_object_put(gobj); dee53e7fb3ee01 Jerome Glisse 2012-07-02 480 up_read(&rdev->exclusive_lock); 66fb975494d21e Min Li 2023-05-26 481 r = radeon_gem_handle_lockup(rdev, r); 771fe6b912fca5 Jerome Glisse 2009-06-05 482 return r; 771fe6b912fca5 Jerome Glisse 2009-06-05 483 } 771fe6b912fca5 Jerome Glisse 2009-06-05 484
Am 26.05.23 um 14:37 schrieb Min Li:
Userspace can race to free the gobj(robj converted from), robj should not be accessed again after drm_gem_object_put, otherwith it will result in use-after-free.
Signed-off-by: Min Li lm0963hack@gmail.com
drivers/gpu/drm/radeon/radeon_gem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/radeon/radeon_gem.c b/drivers/gpu/drm/radeon/radeon_gem.c index bdc5af23f005..450c7cbdd28a 100644 --- a/drivers/gpu/drm/radeon/radeon_gem.c +++ b/drivers/gpu/drm/radeon/radeon_gem.c @@ -478,7 +478,7 @@ int radeon_gem_set_domain_ioctl(struct drm_device *dev, void *data, drm_gem_object_put(gobj); up_read(&rdev->exclusive_lock);
- r = radeon_gem_handle_lockup(robj->rdev, r);
- r = radeon_gem_handle_lockup(rdev, r);
This also makes the robj unused which the kernel test robot also complained about.
Please remove that local variable and re-submit.
Apart from that the patch looks good to me, Christian.
return r; }
linaro-mm-sig@lists.linaro.org
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Christian König -
kernel test robot -
Min Li