| Message ID | 20220621012811.2683313-5-kpsingh@kernel.org (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | BPF |
| Headers | show |
| Series | Add bpf_getxattr | expand |
Hi KP,
I love your patch! Perhaps something to improve:
[auto build test WARNING on bpf-next/master]
url: https://github.com/intel-lab-lkp/linux/commits/KP-Singh/Add-bpf_getxattr/20220621-093013
base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
config: mips-allyesconfig (https://download.01.org/0day-ci/archive/20220621/202206211053.VsuVPf7q-lkp@intel.com/config)
compiler: mips-linux-gcc (GCC) 11.3.0
reproduce (this is a W=1 build):
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/dd49d2ffb18adceafa98bd517008f59aa9bc910b
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review KP-Singh/Add-bpf_getxattr/20220621-093013
git checkout dd49d2ffb18adceafa98bd517008f59aa9bc910b
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.3.0 make.cross W=1 O=build_dir ARCH=mips SHELL=/bin/bash kernel/
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
>> kernel/trace/bpf_trace.c:1185:25: warning: no previous prototype for 'bpf_getxattr' [-Wmissing-prototypes]
1185 | noinline __weak ssize_t bpf_getxattr(struct dentry *dentry, struct inode *inode,
| ^~~~~~~~~~~~
vim +/bpf_getxattr +1185 kernel/trace/bpf_trace.c
1184
> 1185 noinline __weak ssize_t bpf_getxattr(struct dentry *dentry, struct inode *inode,
1186 const char *name, void *value, int size)
1187 {
1188 return __vfs_getxattr(dentry, inode, name, value, size);
1189 }
1190
Hi KP,
I love your patch! Perhaps something to improve:
[auto build test WARNING on bpf-next/master]
url: https://github.com/intel-lab-lkp/linux/commits/KP-Singh/Add-bpf_getxattr/20220621-093013
base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
config: x86_64-randconfig-a015-20220620 (https://download.01.org/0day-ci/archive/20220621/202206211035.p3LxbVfK-lkp@intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project af6d2a0b6825e71965f3e2701a63c239fa0ad70f)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/dd49d2ffb18adceafa98bd517008f59aa9bc910b
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review KP-Singh/Add-bpf_getxattr/20220621-093013
git checkout dd49d2ffb18adceafa98bd517008f59aa9bc910b
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash kernel/trace/
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
>> kernel/trace/bpf_trace.c:1185:25: warning: no previous prototype for function 'bpf_getxattr' [-Wmissing-prototypes]
noinline __weak ssize_t bpf_getxattr(struct dentry *dentry, struct inode *inode,
^
kernel/trace/bpf_trace.c:1185:17: note: declare 'static' if the function is not intended to be used outside of this translation unit
noinline __weak ssize_t bpf_getxattr(struct dentry *dentry, struct inode *inode,
^
static
1 warning generated.
vim +/bpf_getxattr +1185 kernel/trace/bpf_trace.c
1184
> 1185 noinline __weak ssize_t bpf_getxattr(struct dentry *dentry, struct inode *inode,
1186 const char *name, void *value, int size)
1187 {
1188 return __vfs_getxattr(dentry, inode, name, value, size);
1189 }
1190
On Tue, Jun 21, 2022 at 5:20 AM kernel test robot <lkp@intel.com> wrote: > > Hi KP, > > I love your patch! Perhaps something to improve: > > [auto build test WARNING on bpf-next/master] > > url: https://github.com/intel-lab-lkp/linux/commits/KP-Singh/Add-bpf_getxattr/20220621-093013 > base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master > config: x86_64-randconfig-a015-20220620 (https://download.01.org/0day-ci/archive/20220621/202206211035.p3LxbVfK-lkp@intel.com/config) > compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project af6d2a0b6825e71965f3e2701a63c239fa0ad70f) > reproduce (this is a W=1 build): > 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/dd49d2ffb18adceafa98bd517008f59aa9bc910b > git remote add linux-review https://github.com/intel-lab-lkp/linux > git fetch --no-tags linux-review KP-Singh/Add-bpf_getxattr/20220621-093013 > git checkout dd49d2ffb18adceafa98bd517008f59aa9bc910b > # save the config file > mkdir build_dir && cp config build_dir/.config > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash kernel/trace/ > > If you fix the issue, kindly add following tag where applicable > Reported-by: kernel test robot <lkp@intel.com> > > All warnings (new ones prefixed by >>): > > >> kernel/trace/bpf_trace.c:1185:25: warning: no previous prototype for function 'bpf_getxattr' [-Wmissing-prototypes] > noinline __weak ssize_t bpf_getxattr(struct dentry *dentry, struct inode *inode, > ^ > kernel/trace/bpf_trace.c:1185:17: note: declare 'static' if the function is not intended to be used outside of this translation unit > noinline __weak ssize_t bpf_getxattr(struct dentry *dentry, struct inode *inode, > ^ > static > 1 warning generated. > So it looks like this needs a function prototype. Let's do an initial round of reviews on this series and I can respin with something like: diff --git a/kernel/trace/bpf_trace.h b/kernel/trace/bpf_trace.h index 9acbc11ac7bb..3f62e5d35037 100644 --- a/kernel/trace/bpf_trace.h +++ b/kernel/trace/bpf_trace.h @@ -25,6 +25,11 @@ TRACE_EVENT(bpf_trace_printk, TP_printk("%s", __get_str(bpf_string)) ); +/* Prototypes for kernel functions exposed to tracing and LSM + * programs + */ +ssize_t bpf_getxattr(struct dentry *dentry, struct inode *inode, + const char *name, void *value, int size); #endif /* _TRACE_BPF_TRACE_H */ (or anything else folks suggest) - KP > > vim +/bpf_getxattr +1185 kernel/trace/bpf_trace.c > > 1184 > > 1185 noinline __weak ssize_t bpf_getxattr(struct dentry *dentry, struct inode *inode, > 1186 const char *name, void *value, int size) > 1187 { > 1188 return __vfs_getxattr(dentry, inode, name, value, size); > 1189 } > 1190 > > -- > 0-DAY CI Kernel Test Service > https://01.org/lkp
On Tue, Jun 21, 2022 at 12:48:08PM IST, KP Singh wrote: > On Tue, Jun 21, 2022 at 5:20 AM kernel test robot <lkp@intel.com> wrote: > > > > Hi KP, > > > > I love your patch! Perhaps something to improve: > > > > [auto build test WARNING on bpf-next/master] > > > > url: https://github.com/intel-lab-lkp/linux/commits/KP-Singh/Add-bpf_getxattr/20220621-093013 > > base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master > > config: x86_64-randconfig-a015-20220620 (https://download.01.org/0day-ci/archive/20220621/202206211035.p3LxbVfK-lkp@intel.com/config) > > compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project af6d2a0b6825e71965f3e2701a63c239fa0ad70f) > > reproduce (this is a W=1 build): > > 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/dd49d2ffb18adceafa98bd517008f59aa9bc910b > > git remote add linux-review https://github.com/intel-lab-lkp/linux > > git fetch --no-tags linux-review KP-Singh/Add-bpf_getxattr/20220621-093013 > > git checkout dd49d2ffb18adceafa98bd517008f59aa9bc910b > > # save the config file > > mkdir build_dir && cp config build_dir/.config > > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash kernel/trace/ > > > > If you fix the issue, kindly add following tag where applicable > > Reported-by: kernel test robot <lkp@intel.com> > > > > All warnings (new ones prefixed by >>): > > > > >> kernel/trace/bpf_trace.c:1185:25: warning: no previous prototype for function 'bpf_getxattr' [-Wmissing-prototypes] > > noinline __weak ssize_t bpf_getxattr(struct dentry *dentry, struct inode *inode, > > ^ > > kernel/trace/bpf_trace.c:1185:17: note: declare 'static' if the function is not intended to be used outside of this translation unit > > noinline __weak ssize_t bpf_getxattr(struct dentry *dentry, struct inode *inode, > > ^ > > static > > 1 warning generated. > > > > So it looks like this needs a function prototype. Let's do an initial round > of reviews on this series and I can respin with something like: > > diff --git a/kernel/trace/bpf_trace.h b/kernel/trace/bpf_trace.h > index 9acbc11ac7bb..3f62e5d35037 100644 > --- a/kernel/trace/bpf_trace.h > +++ b/kernel/trace/bpf_trace.h > @@ -25,6 +25,11 @@ TRACE_EVENT(bpf_trace_printk, > TP_printk("%s", __get_str(bpf_string)) > ); > > +/* Prototypes for kernel functions exposed to tracing and LSM > + * programs > + */ > +ssize_t bpf_getxattr(struct dentry *dentry, struct inode *inode, > + const char *name, void *value, int size); > #endif /* _TRACE_BPF_TRACE_H */ > > (or anything else folks suggest) > You can silence this warning using __diag_push, e.g. see kfunc definitions in net/netfilter/nf_conntrack_bpf.c. > - KP > > > > > vim +/bpf_getxattr +1185 kernel/trace/bpf_trace.c > > > > 1184 > > > 1185 noinline __weak ssize_t bpf_getxattr(struct dentry *dentry, struct inode *inode, > > 1186 const char *name, void *value, int size) > > 1187 { > > 1188 return __vfs_getxattr(dentry, inode, name, value, size); > > 1189 } > > 1190 > > > > -- > > 0-DAY CI Kernel Test Service > > https://01.org/lkp -- Kartikeya
On Tue, Jun 21, 2022 at 2:41 PM Kumar Kartikeya Dwivedi <memxor@gmail.com> wrote: > > On Tue, Jun 21, 2022 at 12:48:08PM IST, KP Singh wrote: > > On Tue, Jun 21, 2022 at 5:20 AM kernel test robot <lkp@intel.com> wrote: > > > > > > Hi KP, > > > > > > I love your patch! Perhaps something to improve: > > > > > > [auto build test WARNING on bpf-next/master] [...] > > > > You can silence this warning using __diag_push, e.g. see kfunc definitions in > net/netfilter/nf_conntrack_bpf.c. Thanks, done. > > > - KP > > > > > > > > vim +/bpf_getxattr +1185 kernel/trace/bpf_trace.c > > > > > > 1184 > > > > 1185 noinline __weak ssize_t bpf_getxattr(struct dentry *dentry, struct inode *inode, > > > 1186 const char *name, void *value, int size) > > > 1187 { > > > 1188 return __vfs_getxattr(dentry, inode, name, value, size); > > > 1189 } > > > 1190 > > > > > > -- > > > 0-DAY CI Kernel Test Service > > > https://01.org/lkp > > -- > Kartikeya
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 4be976cf7d63..b5682d55ebde 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -20,6 +20,7 @@ #include <linux/fprobe.h> #include <linux/bsearch.h> #include <linux/sort.h> +#include <linux/xattr.h> #include <net/bpf_sk_storage.h> @@ -1181,6 +1182,41 @@ static const struct bpf_func_proto bpf_get_func_arg_cnt_proto = { .arg1_type = ARG_PTR_TO_CTX, }; +noinline __weak ssize_t bpf_getxattr(struct dentry *dentry, struct inode *inode, + const char *name, void *value, int size) +{ + return __vfs_getxattr(dentry, inode, name, value, size); +} + +BTF_SET_START(bpf_trace_kfunc_ids) +BTF_ID(func, bpf_getxattr) +BTF_SET_END(bpf_trace_kfunc_ids) + +BTF_SET_START(bpf_trace_sleepable_kfunc_ids) +BTF_ID(func, bpf_getxattr) +BTF_SET_END(bpf_trace_sleepable_kfunc_ids) + +static const struct btf_kfunc_id_set bpf_trace_kfunc_set = { + .owner = THIS_MODULE, + .check_set = &bpf_trace_kfunc_ids, + .sleepable_set = &bpf_trace_sleepable_kfunc_ids, +}; + +static int __init bpf_trace_kfunc_init(void) +{ + int ret; + + ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, + &bpf_trace_kfunc_set); + if (!ret) + return ret; + + return register_btf_kfunc_id_set(BPF_PROG_TYPE_LSM, + &bpf_trace_kfunc_set); + +} +late_initcall(bpf_trace_kfunc_init); + static const struct bpf_func_proto * bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) {
LSMs like SELinux store security state in xattrs. bpf_getxattr enables BPF LSM to implement similar functionality. In combination with bpf_local_storage, xattrs can be used to develop more complex security policies. This kfunc wraps around __vfs_getxattr which can sleep and is, therefore, limited to sleepable programs using the newly added sleepable_set for kfuncs. Signed-off-by: KP Singh <kpsingh@kernel.org> --- kernel/trace/bpf_trace.c | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+)