Author: andrew
Date: Tue Oct 13 10:26:15 2020
New Revision: 366665
URL: https://svnweb.freebsd.org/changeset/base/366665
Log:
Fix write only mappings on arm64
When trapping on a wrote access to a buffer the kernel has mapped as write
only we should only pass the VM_PROT_WRITE flag. Previously the call to
vm_fault_trap as the VM_PROT_READ flag was unexpected.
Reported by: manu
Sponsored by: Innovate UK
Modified:
head/sys/arm64/arm64/trap.c
head/tests/sys/vm/mmap_test.c
Modified: head/sys/arm64/arm64/trap.c
==============================================================================
--- head/sys/arm64/arm64/trap.c Tue Oct 13 08:14:33 2020 (r366664)
+++ head/sys/arm64/arm64/trap.c Tue Oct 13 10:26:15 2020 (r366665)
@@ -301,7 +301,7 @@ data_abort(struct thread *td, struct trapframe *frame,
break;
default:
ftype = (esr & ISS_DATA_WnR) == 0 ? VM_PROT_READ :
- VM_PROT_READ | VM_PROT_WRITE;
+ VM_PROT_WRITE;
break;
}
Modified: head/tests/sys/vm/mmap_test.c
==============================================================================
--- head/tests/sys/vm/mmap_test.c Tue Oct 13 08:14:33 2020
(r366664)
+++ head/tests/sys/vm/mmap_test.c Tue Oct 13 10:26:15 2020
(r366665)
@@ -259,6 +259,21 @@ ATF_TC_BODY(mmap__dev_zero_shared, tc)
close(fd);
}
+ATF_TC_WITHOUT_HEAD(mmap__write_only);
+ATF_TC_BODY(mmap__write_only, tc)
+{
+ void *p;
+ int pagesize;
+
+ ATF_REQUIRE((pagesize = getpagesize()) > 0);
+ p = mmap(NULL, pagesize, PROT_WRITE, MAP_ANON, -1, 0);
+ ATF_REQUIRE(p != MAP_FAILED);
+
+ *(volatile uint32_t *)p = 0x12345678;
+
+ munmap(p, pagesize);
+}
+
ATF_TP_ADD_TCS(tp)
{
@@ -266,6 +281,7 @@ ATF_TP_ADD_TCS(tp)
ATF_TP_ADD_TC(tp, mmap__bad_arguments);
ATF_TP_ADD_TC(tp, mmap__dev_zero_private);
ATF_TP_ADD_TC(tp, mmap__dev_zero_shared);
+ ATF_TP_ADD_TC(tp, mmap__write_only);
return (atf_no_error());
}
_______________________________________________
svn-src-head@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/svn-src-head
To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
