diff options
| -rw-r--r-- | libsandbox/trace.c | 14 | ||||
| -rw-r--r-- | localdecls.h | 4 | ||||
| -rw-r--r-- | tests/Makefile.am | 3 | ||||
| -rwxr-xr-x | tests/script-13.sh | 5 | ||||
| -rw-r--r-- | tests/script.at | 1 | ||||
| -rw-r--r-- | tests/tests.h | 4 | ||||
| -rw-r--r-- | tests/trace-memory_static_tst.c | 62 |
7 files changed, 92 insertions, 1 deletions
diff --git a/libsandbox/trace.c b/libsandbox/trace.c index 99ef8cd..f9194fe 100644 --- a/libsandbox/trace.c +++ b/libsandbox/trace.c @@ -59,6 +59,11 @@ static long _do_ptrace(enum __ptrace_request request, const char *srequest, void } sched_yield(); goto try_again; + } else if (errno == EIO || errno == EFAULT) { + /* This comes up when the child itself tries to use a bad pointer. + * That's not something the sandbox should abort on. #560396 + */ + return ret; } else if (!errno) if (request == PTRACE_PEEKDATA || request == PTRACE_PEEKTEXT || @@ -140,7 +145,16 @@ static char *do_peekstr(unsigned long lptr) while (1) { a = lptr & (sizeof(long) - 1); lptr -= a; + errno = 0; s.val = do_peekdata(lptr); + if (unlikely(errno)) { + if (errno == EIO || errno == EFAULT) { + ret[0] = '\0'; + return ret; + } + sb_ebort("ISE:do_peekstr:do_peekdata(%#lx) failed: %s\n", + lptr, strerror(errno)); + } for (i = a; i < sizeof(long); ++i) { ret[l++] = s.x[i]; if (!s.x[i]) diff --git a/localdecls.h b/localdecls.h index 0e11fea..ecc5856 100644 --- a/localdecls.h +++ b/localdecls.h @@ -102,6 +102,10 @@ typedef struct user_regs_struct trace_regs; #ifndef offsetof #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER) #endif +#define ALIGN_DOWN(base, size) ((base) & -(size)) +#define ALIGN_UP(base, size) ALIGN_DOWN((base) + (size) - 1, (size)) +#define PTR_ALIGN_DOWN(base, size) ((__typeof__(base))ALIGN_DOWN((uintptr_t)(base), (size))) +#define PTR_ALIGN_UP(base, size) ((__typeof__(base))ALIGN_UP((uintptr_t)(base), (size))) /* If the system is old and does not support *at funcs, then define * it ourself. Shouldn't matter based on how we use it. diff --git a/tests/Makefile.am b/tests/Makefile.am index 0f0c249..3627344 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -76,7 +76,8 @@ check_PROGRAMS = \ pipe-fork_static_tst \ sb_printf_tst \ sigsuspend-zsh_tst \ - sigsuspend-zsh_static_tst + sigsuspend-zsh_static_tst \ + trace-memory_static_tst dist_check_SCRIPTS = \ $(wildcard $(srcdir)/*-[0-9]*.sh) \ diff --git a/tests/script-13.sh b/tests/script-13.sh new file mode 100755 index 0000000..24a0e3b --- /dev/null +++ b/tests/script-13.sh @@ -0,0 +1,5 @@ +#!/bin/sh +# make sure poking remote addresses works even when they're bad/unaligned #560396 +[ "${at_xfail}" = "yes" ] && exit 77 # see script-0 + +trace-memory_static_tst diff --git a/tests/script.at b/tests/script.at index f07a8f1..58a5077 100644 --- a/tests/script.at +++ b/tests/script.at @@ -10,3 +10,4 @@ SB_CHECK(9, [wait errpipe... done OK!]) SB_CHECK(10) SB_CHECK(11) SB_CHECK(12) +SB_CHECK(13) diff --git a/tests/tests.h b/tests/tests.h index 72c678c..51dc68a 100644 --- a/tests/tests.h +++ b/tests/tests.h @@ -1,5 +1,9 @@ #include "headers.h" +/* Make sure assert() works in tests. */ +#undef NDEBUG +#include <assert.h> + #define _msg(std, fmt, args...) fprintf(std, "%s:%s():%i: " fmt "\n", __FILE__, __func__, __LINE__, ##args) #define _stderr_msg(fmt, args...) _msg(stderr, fmt, ##args) #define _stderr_pmsg(fmt, args...) _msg(stderr, fmt ": %s", ##args, strerror(errno)) diff --git a/tests/trace-memory_static_tst.c b/tests/trace-memory_static_tst.c new file mode 100644 index 0000000..14c6477 --- /dev/null +++ b/tests/trace-memory_static_tst.c @@ -0,0 +1,62 @@ +/* + * Make sure the process_vm_readv func can work with strings with different + * alignments and lengths. + * + * https://bugs.gentoo.org/560396 + */ + +/* We want to make some bad calls. */ +#undef _FORTIFY_SOURCES + +#include "tests.h" + +/* Make sure the buffer spans multiple pages. */ +#define SIZE 0x1000 +/* Make sure the buffer has plenty of slack space before/after. */ +static char buf[SIZE * 8]; + +/* The smaller the span, the # of calls goes up: O(N*N*2+N). */ +#define COUNT 0x20 +#define STRIDE (SIZE / COUNT) + +/* Some hacks to defeat gcc warnings so we can use bad pointers. */ +volatile uintptr_t offset = 0; +#define non_const_ptr(ptr) ((void *)((uintptr_t)(ptr) + offset)) + +#define check_ptr(addr) \ +({ \ + printf(" open(%p)\n", addr); \ + ret = open(non_const_ptr(addr), O_RDONLY); \ + assert(ret == -1 && errno == EFAULT); \ +}) + +int main(int argc, char *argv[]) +{ + int ret; + char *path = PTR_ALIGN_UP((char *)buf, SIZE); + size_t start, end; + + setbuf(stdout, NULL); + + printf("some bad pointers\n"); + check_ptr(NULL); + check_ptr((void *)-1); + + printf("lots of good pointers\n"); + printf(" buf = %p\n", buf); + printf(" path = %p\n", path); + + for (start = 0; start < SIZE * 2 + STRIDE; start += STRIDE) { + char *p = path + start; + for (end = start + STRIDE; end < SIZE * 2 + STRIDE; end += STRIDE) { + size_t len = end - start; + printf(" open(%p -> %p [+%#zx])\n", p, p + len, len); + memset(p, 'a', len); + path[end] = '\0'; + ret = open(p, O_RDONLY); + assert(ret == -1 && (errno == ENOENT || errno == ENAMETOOLONG)); + } + } + + return 0; +} |