git: 1a80a157cbe8 - main - ptrace: Do not pass a negative resid to proc_rwmem()

From: Mark Johnston <markj_at_FreeBSD.org>
Date: Mon, 31 Mar 2025 09:06:33 UTC
The branch main has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=1a80a157cbe823ba75bb88823dbf1b245fe87c99

commit 1a80a157cbe823ba75bb88823dbf1b245fe87c99
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2025-03-29 08:54:48 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2025-03-31 09:01:09 +0000

    ptrace: Do not pass a negative resid to proc_rwmem()
    
    While here, avoid truncting uio_resid in proc_rwmem().
    
    Reviewed by:    kib
    MFC after:      2 weeks
    Differential Revision:  https://reviews.freebsd.org/D49479
---
 sys/kern/sys_process.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/sys/kern/sys_process.c b/sys/kern/sys_process.c
index c7dd505d97ca..5126f34e3dc3 100644
--- a/sys/kern/sys_process.c
+++ b/sys/kern/sys_process.c
@@ -387,7 +387,7 @@ proc_rwmem(struct proc *p, struct uio *uio)
 		/*
 		 * How many bytes to copy
 		 */
-		len = min(PAGE_SIZE - page_offset, uio->uio_resid);
+		len = MIN(PAGE_SIZE - page_offset, uio->uio_resid);
 
 		/*
 		 * Fault and hold the page on behalf of the process.
@@ -1382,6 +1382,10 @@ kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data)
 
 	case PT_IO:
 		piod = addr;
+		if (piod->piod_len > SSIZE_MAX) {
+			error = EINVAL;
+			goto out;
+		}
 		iov.iov_base = piod->piod_addr;
 		iov.iov_len = piod->piod_len;
 		uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs;