diff options
Diffstat (limited to 'gdb/common/linux-ptrace.c')
| -rw-r--r-- | gdb/common/linux-ptrace.c | 105 |
1 files changed, 88 insertions, 17 deletions
diff --git a/gdb/common/linux-ptrace.c b/gdb/common/linux-ptrace.c index fdec5d6291c..ae17786eb7a 100644 --- a/gdb/common/linux-ptrace.c +++ b/gdb/common/linux-ptrace.c @@ -49,7 +49,7 @@ linux_ptrace_attach_warnings (pid_t pid, struct buffer *buffer) (int) pid); } -#ifdef __i386__ +#if defined __i386__ || defined __x86_64__ /* Address of the 'ret' instruction in asm code block below. */ extern void (linux_ptrace_test_ret_to_nx_instr) (void); @@ -60,15 +60,17 @@ extern void (linux_ptrace_test_ret_to_nx_instr) (void); #include <sys/wait.h> #include <stdint.h> -#endif /* __i386__ */ +#endif /* defined __i386__ || defined __x86_64__ */ /* Test broken off-trunk Linux kernel patchset for NX support on i386. It was - removed in Fedora kernel 88fa1f0332d188795ed73d7ac2b1564e11a0b4cd. */ + removed in Fedora kernel 88fa1f0332d188795ed73d7ac2b1564e11a0b4cd. + + Test also x86_64 arch for PaX support. */ static void linux_ptrace_test_ret_to_nx (void) { -#ifdef __i386__ +#if defined __i386__ || defined __x86_64__ pid_t child, got_pid; gdb_byte *return_address, *pc; long l; @@ -101,39 +103,105 @@ linux_ptrace_test_ret_to_nx (void) strerror (errno)); else { +#if defined __i386__ asm volatile ("pushl %0;" ".globl linux_ptrace_test_ret_to_nx_instr;" "linux_ptrace_test_ret_to_nx_instr:" "ret" : : "r" (return_address) : "%esp", "memory"); +#elif defined __x86_64__ + asm volatile ("pushq %0;" + ".globl linux_ptrace_test_ret_to_nx_instr;" + "linux_ptrace_test_ret_to_nx_instr:" + "ret" + : : "r" (return_address) : "%rsp", "memory"); +#else +# error "!__i386__ && !__x86_64__" +#endif gdb_assert_not_reached ("asm block did not terminate"); } _exit (1); } + errno = 0; got_pid = waitpid (child, &status, 0); - gdb_assert (got_pid == child); - gdb_assert (WIFSTOPPED (status)); + if (got_pid != child) + { + warning (_("linux_ptrace_test_ret_to_nx: waitpid returned %ld: %s"), + (long) got_pid, strerror (errno)); + return; + } + + if (WIFSIGNALED (status)) + { + if (WTERMSIG (status) != SIGKILL) + warning (_("linux_ptrace_test_ret_to_nx: WTERMSIG %d is not SIGKILL!"), + (int) WTERMSIG (status)); + else + warning (_("Cannot call inferior functions, Linux kernel PaX " + "protection forbids return to non-executable pages!")); + return; + } + + if (!WIFSTOPPED (status)) + { + warning (_("linux_ptrace_test_ret_to_nx: status %d is not WIFSTOPPED!"), + status); + return; + } /* We may get SIGSEGV due to missing PROT_EXEC of the return_address. */ - gdb_assert (WSTOPSIG (status) == SIGTRAP || WSTOPSIG (status) == SIGSEGV); + if (WSTOPSIG (status) != SIGTRAP && WSTOPSIG (status) != SIGSEGV) + { + warning (_("linux_ptrace_test_ret_to_nx: " + "WSTOPSIG %d is neither SIGTRAP nor SIGSEGV!"), + (int) WSTOPSIG (status)); + return; + } errno = 0; +#if defined __i386__ l = ptrace (PTRACE_PEEKUSER, child, (void *) (uintptr_t) (EIP * 4), NULL); - gdb_assert (errno == 0); +#elif defined __x86_64__ + l = ptrace (PTRACE_PEEKUSER, child, (void *) (uintptr_t) (RIP * 8), NULL); +#else +# error "!__i386__ && !__x86_64__" +#endif + if (errno != 0) + { + warning (_("linux_ptrace_test_ret_to_nx: Cannot PTRACE_PEEKUSER: %s"), + strerror (errno)); + return; + } pc = (void *) (uintptr_t) l; if (ptrace (PTRACE_KILL, child, NULL, NULL) != 0) - warning (_("linux_ptrace_test_ret_to_nx: Cannot PTRACE_KILL: %s"), - strerror (errno)); + { + warning (_("linux_ptrace_test_ret_to_nx: Cannot PTRACE_KILL: %s"), + strerror (errno)); + return; + } else { int kill_status; + errno = 0; got_pid = waitpid (child, &kill_status, 0); - gdb_assert (got_pid == child); - gdb_assert (WIFSIGNALED (kill_status)); + if (got_pid != child) + { + warning (_("linux_ptrace_test_ret_to_nx: " + "PTRACE_KILL waitpid returned %ld: %s"), + (long) got_pid, strerror (errno)); + return; + } + if (!WIFSIGNALED (kill_status)) + { + warning (_("linux_ptrace_test_ret_to_nx: " + "PTRACE_KILL status %d is not WIFSIGNALED!"), + status); + return; + } } /* + 1 is there as x86* stops after the 'int3' instruction. */ @@ -150,11 +218,14 @@ linux_ptrace_test_ret_to_nx (void) return; } - gdb_assert ((void (*) (void)) pc == &linux_ptrace_test_ret_to_nx_instr); - - warning (_("Cannot call inferior functions, you have broken " - "Linux kernel i386 NX (non-executable pages) support!")); -#endif /* __i386__ */ + if ((void (*) (void)) pc != &linux_ptrace_test_ret_to_nx_instr) + warning (_("linux_ptrace_test_ret_to_nx: PC %p is neither near return " + "address %p nor is the return instruction %p!"), + pc, return_address, &linux_ptrace_test_ret_to_nx_instr); + else + warning (_("Cannot call inferior functions, you have broken " + "Linux kernel i386 NX (non-executable pages) support!")); +#endif /* defined __i386__ || defined __x86_64__ */ } /* Display possible problems on this system. Display them only once per GDB |