diff options
Diffstat (limited to 'run-as')
-rw-r--r-- | run-as/run-as.c | 43 |
1 files changed, 24 insertions, 19 deletions
diff --git a/run-as/run-as.c b/run-as/run-as.c index 3c0ecc4..cc05e63 100644 --- a/run-as/run-as.c +++ b/run-as/run-as.c @@ -36,9 +36,9 @@ /* * WARNING WARNING WARNING WARNING * - * This program runs as set-uid root on Android production devices. - * Be very conservative when modifying it to avoid any serious - * security issue. Keep in mind the following: + * This program runs with CAP_SETUID and CAP_SETGID capabilities on Android + * production devices. Be very conservative when modifying it to avoid any + * serious security issue. Keep in mind the following: * * - This program should only run for the 'root' or 'shell' users * @@ -61,14 +61,19 @@ * * run-as <package-name> <command> <args> * - * The 'run-as' binary is setuid, but will check the following: + * The 'run-as' binary is installed with CAP_SETUID and CAP_SETGID file + * capabilities, but will check the following: * * - that it is invoked from the 'shell' or 'root' user (abort otherwise) * - that '<package-name>' is the name of an installed and debuggable package * - that the package's data directory is well-formed (see package.c) * - * If so, it will cd to the package's data directory, drop to the application's - * user id / group id then run the command there. + * If so, it will drop to the application's user id / group id, cd to the + * package's data directory, then run the command there. + * + * NOTE: In the future it might not be possible to cd to the package's data + * directory under that package's user id / group id, in which case this + * utility will need to be changed accordingly. * * This can be useful for a number of different things on production devices: * @@ -141,19 +146,6 @@ int main(int argc, char **argv) return 1; } - /* then move to it */ - { - int ret; - do { - ret = chdir(info.dataDir); - } while (ret < 0 && errno == EINTR); - - if (ret < 0) { - panic("Could not cd to package's data directory: %s\n", strerror(errno)); - return 1; - } - } - /* Ensure that we change all real/effective/saved IDs at the * same time to avoid nasty surprises. */ @@ -168,6 +160,19 @@ int main(int argc, char **argv) return 1; } + /* cd into the data directory */ + { + int ret; + do { + ret = chdir(info.dataDir); + } while (ret < 0 && errno == EINTR); + + if (ret < 0) { + panic("Could not cd to package's data directory: %s\n", strerror(errno)); + return 1; + } + } + /* User specified command for exec. */ if (argc >= 3 ) { if (execvp(argv[2], argv+2) < 0) { |