[PATCH 02/44] perf augmented_raw_syscalls: Copy strings from all syscalls with 1st or 2nd string arg

Arnaldo Carvalho de Melo
2019-04-02T16:06:14Z

From: Arnaldo Carvalho de Melo <acme@redhat.com>

Gets the augmented_raw_syscalls a bit more useful as-is, add a comment
stating that the intent is to have all this in a map populated by
userspace via the 'syscalls' BPF map, that right now has only a flag
stating if the syscall is filtered or not.

With it:

# grep -B1 augmented_raw ~/.perfconfig
[trace]
add_events = /home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.o
#
# perf trace -e string
weechat/6001 stat("/etc/localtime", 0x7ffe22c23d10) = 0
gnome-shell/1943 openat(AT_FDCWD, "/proc/self/stat", O_RDONLY) = 81
weechat/6001 stat("/etc/localtime", 0x7ffe22c23d10) = 0
gmain/2475 inotify_add_watch(20<anon_inode:inotify>, "/home/acme/.config/firewall", 16789454) = -1 ENOENT (No such file or directory)
gmain/2391 inotify_add_watch(3<anon_inode:inotify>, "", 16789454) = -1 ENOENT (No such file or directory)
gmain/2391 inotify_add_watch(3<anon_inode:inotify>, "/var/cache/app-info/yaml", 16789454) = -1 ENOENT (No such file or directory)
gmain/2391 inotify_add_watch(3<anon_inode:inotify>, "/var/lib/app-info/xmls", 16789454) = -1 ENOENT (No such file or directory)
gmain/2391 inotify_add_watch(3<anon_inode:inotify>, "/var/lib/app-info/yaml", 16789454) = -1 ENOENT (No such file or directory)
gmain/2391 inotify_add_watch(3<anon_inode:inotify>, "/usr/share/app-info/yaml", 16789454) = -1 ENOENT (No such file or directory)
gmain/2391 inotify_add_watch(3<anon_inode:inotify>, "/usr/local/share/app-info/xmls", 16789454) = -1 ENOENT (No such file or directory)
gmain/2391 inotify_add_watch(3<anon_inode:inotify>, "/usr/local/share/app-info/yaml", 16789454) = -1 ENOENT (No such file or directory)
gmain/2391 inotify_add_watch(3<anon_inode:inotify>, "/home/acme/.local/share/app-info/yaml", 16789454) = -1 ENOENT (No such file or directory)
gmain/1121 inotify_add_watch(12<anon_inode:inotify>, "/etc/NetworkManager/VPN", 16789454) = -1 ENOENT (No such file or directory)
weechat/6001 stat("/etc/localtime", 0x7ffe22c23d10) = 0
gmain/2050 inotify_add_watch(8<anon_inode:inotify>, "/home/acme/~", 16789454) = -1 ENOENT (No such file or directory)
gmain/2521 inotify_add_watch(6<anon_inode:inotify>, "/var/lib/fwupd/remotes.d/lvfs-testing", 16789454) = -1 ENOENT (No such file or directory)
weechat/6001 stat("/etc/localtime", 0x7ffe22c23d10) = 0
DOM Worker/22714 ... [continued]: openat()) = 257
FS Broker 3982/3990 openat(AT_FDCWD, "/dev/urandom", O_RDONLY|O_CLOEXEC|O_NOCTTY) = 187
DOMCacheThread/16652 mkdir("/home/acme/.mozilla/firefox/ina67tev.default/storage/default/https+++web.whatsapp.com/cache/morgue/192", S_IRUGO|S_IXUGO|S_IWUSR) = -1 EEXIST (File exists)
^C#

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-a1hxffoy8t43e0wq6bzhp23u@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
.../examples/bpf/augmented_raw_syscalls.c | 150 +++++++++++++++++-
1 file changed, 147 insertions(+), 3 deletions(-)

diff --git a/tools/perf/examples/bpf/augmented_raw_syscalls.c b/tools/perf/examples/bpf/augmented_raw_syscalls.c
index f9b2161e1ca4..9f8b31ad7a49 100644
--- a/tools/perf/examples/bpf/augmented_raw_syscalls.c
+++ b/tools/perf/examples/bpf/augmented_raw_syscalls.c
@@ -44,9 +44,78 @@ struct augmented_filename {
char value[256];
};

-#define SYS_OPEN 2
-#define SYS_ACCESS 21
-#define SYS_OPENAT 257
+/* syscalls where the first arg is a string */
+#define SYS_OPEN 2
+#define SYS_STAT 4
+#define SYS_LSTAT 6
+#define SYS_ACCESS 21
+#define SYS_EXECVE 59
+#define SYS_TRUNCATE 76
+#define SYS_CHDIR 80
+#define SYS_RENAME 82
+#define SYS_MKDIR 83
+#define SYS_RMDIR 84
+#define SYS_CREAT 85
+#define SYS_LINK 86
+#define SYS_UNLINK 87
+#define SYS_SYMLINK 88
+#define SYS_READLINK 89
+#define SYS_CHMOD 90
+#define SYS_CHOWN 92
+#define SYS_LCHOWN 94
+#define SYS_MKNOD 133
+#define SYS_STATFS 137
+#define SYS_PIVOT_ROOT 155
+#define SYS_CHROOT 161
+#define SYS_ACCT 163
+#define SYS_SWAPON 167
+#define SYS_SWAPOFF 168
+#define SYS_DELETE_MODULE 176
+#define SYS_SETXATTR 188
+#define SYS_LSETXATTR 189
+#define SYS_GETXATTR 191
+#define SYS_LGETXATTR 192
+#define SYS_LISTXATTR 194
+#define SYS_LLISTXATTR 195
+#define SYS_REMOVEXATTR 197
+#define SYS_LREMOVEXATTR 198
+#define SYS_MQ_OPEN 240
+#define SYS_MQ_UNLINK 241
+#define SYS_ADD_KEY 248
+#define SYS_REQUEST_KEY 249
+#define SYS_SYMLINKAT 266
+#define SYS_MEMFD_CREATE 319
+
+/* syscalls where the first arg is a string */
+
+#define SYS_PWRITE64 18
+#define SYS_EXECVE 59
+#define SYS_RENAME 82
+#define SYS_QUOTACTL 179
+#define SYS_FSETXATTR 190
+#define SYS_FGETXATTR 193
+#define SYS_FREMOVEXATTR 199
+#define SYS_MQ_TIMEDSEND 242
+#define SYS_REQUEST_KEY 249
+#define SYS_INOTIFY_ADD_WATCH 254
+#define SYS_OPENAT 257
+#define SYS_MKDIRAT 258
+#define SYS_MKNODAT 259
+#define SYS_FCHOWNAT 260
+#define SYS_FUTIMESAT 261
+#define SYS_NEWFSTATAT 262
+#define SYS_UNLINKAT 263
+#define SYS_RENAMEAT 264
+#define SYS_LINKAT 265
+#define SYS_READLINKAT 267
+#define SYS_FCHMODAT 268
+#define SYS_FACCESSAT 269
+#define SYS_UTIMENSAT 280
+#define SYS_NAME_TO_HANDLE_AT 303
+#define SYS_FINIT_MODULE 313
+#define SYS_RENAMEAT2 316
+#define SYS_EXECVEAT 322
+#define SYS_STATX 332

pid_filter(pids_filtered);

@@ -109,11 +178,86 @@ int sys_enter(struct syscall_enter_args *args)
*
* after the ctx memory access to prevent their down stream merging.
*/
+ /*
+ * This table of what args are strings will be provided by userspace,
+ * in the syscalls map, i.e. we will already have to do the lookup to
+ * see if this specific syscall is filtered, so we can as well get more
+ * info about what syscall args are strings or pointers, and how many
+ * bytes to copy, per arg, etc.
+ *
+ * For now hard code it, till we have all the basic mechanisms in place
+ * to automate everything and make the kernel part be completely driven
+ * by information obtained in userspace for each kernel version and
+ * processor architecture, making the kernel part the same no matter what
+ * kernel version or processor architecture it runs on.
+ */
switch (augmented_args.args.syscall_nr) {
+ case SYS_ACCT:
+ case SYS_ADD_KEY:
+ case SYS_CHDIR:
+ case SYS_CHMOD:
+ case SYS_CHOWN:
+ case SYS_CHROOT:
+ case SYS_CREAT:
+ case SYS_DELETE_MODULE:
+ case SYS_EXECVE:
+ case SYS_GETXATTR:
+ case SYS_LCHOWN:
+ case SYS_LGETXATTR:
+ case SYS_LINK:
+ case SYS_LISTXATTR:
+ case SYS_LLISTXATTR:
+ case SYS_LREMOVEXATTR:
+ case SYS_LSETXATTR:
+ case SYS_LSTAT:
+ case SYS_MEMFD_CREATE:
+ case SYS_MKDIR:
+ case SYS_MKNOD:
+ case SYS_MQ_OPEN:
+ case SYS_MQ_UNLINK:
+ case SYS_PIVOT_ROOT:
+ case SYS_READLINK:
+ case SYS_REMOVEXATTR:
+ case SYS_RENAME:
+ case SYS_REQUEST_KEY:
+ case SYS_RMDIR:
+ case SYS_SETXATTR:
+ case SYS_STAT:
+ case SYS_STATFS:
+ case SYS_SWAPOFF:
+ case SYS_SWAPON:
+ case SYS_SYMLINK:
+ case SYS_SYMLINKAT:
+ case SYS_TRUNCATE:
+ case SYS_UNLINK:
case SYS_ACCESS:
case SYS_OPEN: filename_arg = (const void *)args->args[0];
__asm__ __volatile__("": : :"memory");
break;
+ case SYS_EXECVEAT:
+ case SYS_FACCESSAT:
+ case SYS_FCHMODAT:
+ case SYS_FCHOWNAT:
+ case SYS_FGETXATTR:
+ case SYS_FINIT_MODULE:
+ case SYS_FREMOVEXATTR:
+ case SYS_FSETXATTR:
+ case SYS_FUTIMESAT:
+ case SYS_INOTIFY_ADD_WATCH:
+ case SYS_LINKAT:
+ case SYS_MKDIRAT:
+ case SYS_MKNODAT:
+ case SYS_MQ_TIMEDSEND:
+ case SYS_NAME_TO_HANDLE_AT:
+ case SYS_NEWFSTATAT:
+ case SYS_PWRITE64:
+ case SYS_QUOTACTL:
+ case SYS_READLINKAT:
+ case SYS_RENAMEAT:
+ case SYS_RENAMEAT2:
+ case SYS_STATX:
+ case SYS_UNLINKAT:
+ case SYS_UTIMENSAT:
case SYS_OPENAT: filename_arg = (const void *)args->args[1];
break;
}
--
2.20.1