Add arm-specific code to set the system call number.

Fixes rejection of commands due to policy on arm when in intercept mode.
This commit is contained in:
Todd C. Miller
2022-05-12 10:23:27 -06:00
parent 4a7d26c381
commit b99debf92f
2 changed files with 31 additions and 6 deletions

View File

@@ -84,12 +84,12 @@ get_syscallno(struct sudo_ptrace_regs *regs)
}
static inline void
set_syscallno(struct sudo_ptrace_regs *regs, int syscallno)
set_syscallno(pid_t pid, struct sudo_ptrace_regs *regs, int syscallno)
{
if (regs->compat) {
compat_reg_syscall(regs->u.compat) = syscallno;
compat_reg_set_syscall(regs->u.compat, syscallno);
} else {
reg_syscall(regs->u.native) = syscallno;
reg_set_syscall(regs->u.native, syscallno);
}
}
@@ -194,9 +194,9 @@ get_syscallno(struct sudo_ptrace_regs *regs)
}
static inline void
set_syscallno(struct sudo_ptrace_regs *regs, int syscallno)
set_syscallno(pid_t pid, struct sudo_ptrace_regs *regs, int syscallno)
{
reg_syscall(regs->u.native) = syscallno;
reg_set_syscall(regs->u.native, syscallno);
}
static inline unsigned long
@@ -687,7 +687,7 @@ ptrace_fail_syscall(pid_t pid, struct sudo_ptrace_regs *regs, int ecode)
debug_decl(ptrace_fail_syscall, SUDO_DEBUG_EXEC);
/* Cause the syscall to fail by changing its number to -1. */
set_syscallno(regs, -1);
set_syscallno(pid, regs, -1);
if (!ptrace_setregs(pid, regs)) {
sudo_warn(U_("unable to set registers for process %d"), (int)pid);
debug_return_bool(false);

View File

@@ -74,6 +74,13 @@
# define reg_arg2(x) (x).regs[1] /* x1 */
# define reg_arg3(x) (x).regs[2] /* x2 */
# define reg_arg4(x) (x).regs[3] /* x3 */
# define reg_set_syscall(_r, _nr) do { \
struct iovec _iov; \
long syscallno = (_nr); \
_iov.iov_base = &syscallno; \
_iov.iov_len = sizeof(syscallno); \
ptrace(PTRACE_SETREGSET, pid, NT_ARM_SYSTEM_CALL, &_iov); \
} while (0)
#elif defined(__arm__)
/* Note: assumes arm EABI, not OABI */
/* Untested */
@@ -86,6 +93,9 @@
# define reg_arg2(x) (x).ARM_r1
# define reg_arg3(x) (x).ARM_r2
# define reg_arg4(x) (x).ARM_r3
# define reg_set_syscall(_r, _nr) do { \
ptrace(PTRACE_SET_SYSCALL, pid, NULL, _nr); \
} while (0)
#elif defined (__hppa__)
/* Untested (should also support hppa64) */
# define SECCOMP_AUDIT_ARCH AUDIT_ARCH_PARISC
@@ -228,6 +238,9 @@ struct arm_pt_regs {
# define compat_reg_arg2(x) (x).uregs[1] /* r1 */
# define compat_reg_arg3(x) (x).uregs[2] /* r2 */
# define compat_reg_arg4(x) (x).uregs[3] /* r3 */
# define compat_reg_set_syscall(_r, _nr) do { \
ptrace(PTRACE_SET_SYSCALL, pid, NULL, _nr); \
} while (0)
#elif defined(__powerpc64__)
struct ppc_pt_regs {
unsigned int gpr[32];
@@ -263,6 +276,18 @@ struct ppc_pt_regs {
# define compat_reg_set_retval(_r, _v) reg_set_retval(_r, _v)
#endif
/* Set the syscall number the "normal" way by default. */
#ifndef reg_set_syscall
# define reg_set_syscall(_r, _nr) do { \
reg_syscall(_r) = (_nr); \
} while (0)
#endif
#ifndef compat_reg_set_syscall
# define compat_reg_set_syscall(_r, _nr) do { \
compat_reg_syscall(_r) = (_nr); \
} while (0)
#endif
/* Set the syscall return value the "normal" way by default. */
#ifndef reg_set_retval
# define reg_set_retval(_r, _v) do { \