Hi all, I'm trying to read process memory other than the current process in kernel. I was told to use the proc_rwmem function, however I can't get it working properly. At first, I'm trying to read how many elements the environment variables vector has. To do this I tried this from a linprocfs filler function:
struct iovec iov; struct uio tmp_uio; struct ps_strings *pss; int ret_code; buff = malloc(sizeof(struct ps_strings), M_TEMP, M_WAITOK); memset(buff, 0, sizeof(struct ps_strings)); PROC_LOCK_ASSERT(td->td_proc, MA_NOTOWNED); iov.iov_base = (caddr_t) buff; iov.iov_len = sizeof(struct ps_strings); tmp_uio.uio_iov = &iov; tmp_uio.uio_iovcnt = 1; tmp_uio.uio_offset = (off_t)(p->p_sysent->sv_psstrings); tmp_uio.uio_resid = sizeof(struct ps_strings); tmp_uio.uio_segflg = UIO_USERSPACE; tmp_uio.uio_rw = UIO_READ; tmp_uio.uio_td = td; ret_code = proc_rwmem(td->td_proc, &tmp_uio); if (ret_code == 0) { sbuf_printf(sb, "proc_rwmem successfully executed: %d\n", ret_code); } else { sbuf_printf(sb, "Error in proc_rwmem: %d\n", ret_code); } pss = (struct ps_strings *)(iov.iov_base); sbuf_printf(sb, "ps_nargvstr = %d\nps_nenvstr = %d\n", pss->ps_nargvstr, pss->ps_nenvstr); free(buff, M_TEMP); Considering I left security and error handling aside, what is wrong with the code above? proc_rwmem returns 0 indicating no failure, but when I try to print the result, I get random stuff. I thought maybe the problem is in the uio_offset field, but p->p_sysent->sv_psstrings is a vm_offset_t. Is the offset properly specified? If not, what else could be the problem? Thanks in advance. PS: I posted a similar question at forums.freebsd.org but got no answer, that is why I ask here. _______________________________________________ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "freebsd-hackers-unsubscr...@freebsd.org"