diff options
Diffstat (limited to 'fs/exec.c')
-rw-r--r-- | fs/exec.c | 28 |
1 files changed, 22 insertions, 6 deletions
@@ -1049,16 +1049,32 @@ EXPORT_SYMBOL(install_exec_creds); | |||
1049 | * - the caller must hold current->cred_exec_mutex to protect against | 1049 | * - the caller must hold current->cred_exec_mutex to protect against |
1050 | * PTRACE_ATTACH | 1050 | * PTRACE_ATTACH |
1051 | */ | 1051 | */ |
1052 | void check_unsafe_exec(struct linux_binprm *bprm) | 1052 | void check_unsafe_exec(struct linux_binprm *bprm, struct files_struct *files) |
1053 | { | 1053 | { |
1054 | struct task_struct *p = current; | 1054 | struct task_struct *p = current, *t; |
1055 | unsigned long flags; | ||
1056 | unsigned n_fs, n_files, n_sighand; | ||
1055 | 1057 | ||
1056 | bprm->unsafe = tracehook_unsafe_exec(p); | 1058 | bprm->unsafe = tracehook_unsafe_exec(p); |
1057 | 1059 | ||
1058 | if (atomic_read(&p->fs->count) > 1 || | 1060 | n_fs = 1; |
1059 | atomic_read(&p->files->count) > 1 || | 1061 | n_files = 1; |
1060 | atomic_read(&p->sighand->count) > 1) | 1062 | n_sighand = 1; |
1063 | lock_task_sighand(p, &flags); | ||
1064 | for (t = next_thread(p); t != p; t = next_thread(t)) { | ||
1065 | if (t->fs == p->fs) | ||
1066 | n_fs++; | ||
1067 | if (t->files == files) | ||
1068 | n_files++; | ||
1069 | n_sighand++; | ||
1070 | } | ||
1071 | |||
1072 | if (atomic_read(&p->fs->count) > n_fs || | ||
1073 | atomic_read(&p->files->count) > n_files || | ||
1074 | atomic_read(&p->sighand->count) > n_sighand) | ||
1061 | bprm->unsafe |= LSM_UNSAFE_SHARE; | 1075 | bprm->unsafe |= LSM_UNSAFE_SHARE; |
1076 | |||
1077 | unlock_task_sighand(p, &flags); | ||
1062 | } | 1078 | } |
1063 | 1079 | ||
1064 | /* | 1080 | /* |
@@ -1273,7 +1289,7 @@ int do_execve(char * filename, | |||
1273 | bprm->cred = prepare_exec_creds(); | 1289 | bprm->cred = prepare_exec_creds(); |
1274 | if (!bprm->cred) | 1290 | if (!bprm->cred) |
1275 | goto out_unlock; | 1291 | goto out_unlock; |
1276 | check_unsafe_exec(bprm); | 1292 | check_unsafe_exec(bprm, displaced); |
1277 | 1293 | ||
1278 | file = open_exec(filename); | 1294 | file = open_exec(filename); |
1279 | retval = PTR_ERR(file); | 1295 | retval = PTR_ERR(file); |