diff options
| -rw-r--r-- | include/sysemu/seccomp.h | 3 | ||||
| -rw-r--r-- | qemu-options.hx | 12 | ||||
| -rw-r--r-- | qemu-seccomp.c | 19 | ||||
| -rw-r--r-- | vl.c | 24 |
4 files changed, 53 insertions, 5 deletions
diff --git a/include/sysemu/seccomp.h b/include/sysemu/seccomp.h index 23b9c3c789..215138a372 100644 --- a/include/sysemu/seccomp.h +++ b/include/sysemu/seccomp.h @@ -16,8 +16,9 @@ #define QEMU_SECCOMP_H #define QEMU_SECCOMP_SET_DEFAULT (1 << 0) +#define QEMU_SECCOMP_SET_OBSOLETE (1 << 1) #include <seccomp.h> -int seccomp_start(void); +int seccomp_start(uint32_t seccomp_opts); #endif diff --git a/qemu-options.hx b/qemu-options.hx index 9f6e2adfff..72150c6b84 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -4017,13 +4017,21 @@ Old param mode (ARM only). ETEXI DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \ - "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n", + "-sandbox on[,obsolete=allow|deny]\n" \ + " Enable seccomp mode 2 system call filter (default 'off').\n" \ + " use 'obsolete' to allow obsolete system calls that are provided\n" \ + " by the kernel, but typically no longer used by modern\n" \ + " C library implementations.\n", QEMU_ARCH_ALL) STEXI -@item -sandbox @var{arg} +@item -sandbox @var{arg}[,obsolete=@var{string}] @findex -sandbox Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will disable it. The default is 'off'. +@table @option +@item obsolete=@var{string} +Enable Obsolete system calls +@end table ETEXI DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig, diff --git a/qemu-seccomp.c b/qemu-seccomp.c index f66613fc71..8a5fbd2ff1 100644 --- a/qemu-seccomp.c +++ b/qemu-seccomp.c @@ -55,9 +55,22 @@ static const struct QemuSeccompSyscall blacklist[] = { { SCMP_SYS(tuxcall), QEMU_SECCOMP_SET_DEFAULT }, { SCMP_SYS(ulimit), QEMU_SECCOMP_SET_DEFAULT }, { SCMP_SYS(vserver), QEMU_SECCOMP_SET_DEFAULT }, + /* obsolete */ + { SCMP_SYS(readdir), QEMU_SECCOMP_SET_OBSOLETE }, + { SCMP_SYS(_sysctl), QEMU_SECCOMP_SET_OBSOLETE }, + { SCMP_SYS(bdflush), QEMU_SECCOMP_SET_OBSOLETE }, + { SCMP_SYS(create_module), QEMU_SECCOMP_SET_OBSOLETE }, + { SCMP_SYS(get_kernel_syms), QEMU_SECCOMP_SET_OBSOLETE }, + { SCMP_SYS(query_module), QEMU_SECCOMP_SET_OBSOLETE }, + { SCMP_SYS(sgetmask), QEMU_SECCOMP_SET_OBSOLETE }, + { SCMP_SYS(ssetmask), QEMU_SECCOMP_SET_OBSOLETE }, + { SCMP_SYS(sysfs), QEMU_SECCOMP_SET_OBSOLETE }, + { SCMP_SYS(uselib), QEMU_SECCOMP_SET_OBSOLETE }, + { SCMP_SYS(ustat), QEMU_SECCOMP_SET_OBSOLETE }, }; -int seccomp_start(void) + +int seccomp_start(uint32_t seccomp_opts) { int rc = 0; unsigned int i = 0; @@ -70,6 +83,10 @@ int seccomp_start(void) } for (i = 0; i < ARRAY_SIZE(blacklist); i++) { + if (!(seccomp_opts & blacklist[i].set)) { + continue; + } + rc = seccomp_rule_add(ctx, SCMP_ACT_KILL, blacklist[i].num, 0); if (rc < 0) { goto seccomp_return; @@ -271,6 +271,10 @@ static QemuOptsList qemu_sandbox_opts = { .name = "enable", .type = QEMU_OPT_BOOL, }, + { + .name = "obsolete", + .type = QEMU_OPT_STRING, + }, { /* end of list */ } }, }; @@ -1034,7 +1038,25 @@ static int parse_sandbox(void *opaque, QemuOpts *opts, Error **errp) { if (qemu_opt_get_bool(opts, "enable", false)) { #ifdef CONFIG_SECCOMP - if (seccomp_start() < 0) { + uint32_t seccomp_opts = QEMU_SECCOMP_SET_DEFAULT + | QEMU_SECCOMP_SET_OBSOLETE; + const char *value = NULL; + + value = qemu_opt_get(opts, "obsolete"); + if (value) { + if (g_str_equal(value, "allow")) { + seccomp_opts &= ~QEMU_SECCOMP_SET_OBSOLETE; + } else if (g_str_equal(value, "deny")) { + /* this is the default option, this if is here + * to provide a little bit of consistency for + * the command line */ + } else { + error_report("invalid argument for obsolete"); + return -1; + } + } + + if (seccomp_start(seccomp_opts) < 0) { error_report("failed to install seccomp syscall filter " "in the kernel"); return -1; |