strace/linux/mips/get_syscall_args.c
Dmitry V. Levin 25f91fd854 mips o32: do not bail out in get_syscall_args if umoven fails
If the kernel contains commit 84d77d3f06e7e8dea057d10e8ec77ad71f721be3,
both PTRACE_PEEKDATA and process_vm_readv become unavailable when the
process dumpable flag is cleared.  As the first 4 syscall arguments are
still available via registers, do not treat this as get_syscall_args
error.

This condition is triggered and therefore tested by prctl-dumpable test.

* linux/mips/get_syscall_args.c (get_syscall_args) [LINUX_MIPSO32]:
Do not bail out if umoven fails.
2017-08-18 14:30:08 +00:00

33 lines
896 B
C

/* Return -1 on error or 1 on success (never 0!). */
static int
get_syscall_args(struct tcb *tcp)
{
#if defined LINUX_MIPSN64 || defined LINUX_MIPSN32
tcp->u_arg[0] = mips_REG_A0;
tcp->u_arg[1] = mips_REG_A1;
tcp->u_arg[2] = mips_REG_A2;
tcp->u_arg[3] = mips_REG_A3;
tcp->u_arg[4] = mips_REG_A4;
tcp->u_arg[5] = mips_REG_A5;
#elif defined LINUX_MIPSO32
tcp->u_arg[0] = mips_REG_A0;
tcp->u_arg[1] = mips_REG_A1;
tcp->u_arg[2] = mips_REG_A2;
tcp->u_arg[3] = mips_REG_A3;
if (tcp->s_ent->nargs > 4
&& umoven(tcp, mips_REG_SP + 4 * sizeof(tcp->u_arg[0]),
(tcp->s_ent->nargs - 4) * sizeof(tcp->u_arg[0]),
&tcp->u_arg[4]) < 0) {
/*
* Let's proceed with the first 4 arguments
* instead of reporting the failure.
*/
memset(&tcp->u_arg[4], 0,
(tcp->s_ent->nargs - 4) * sizeof(tcp->u_arg[0]));
}
#else
# error unsupported mips abi
#endif
return 1;
}