The branch main has been updated by kib:
URL:
https://cgit.FreeBSD.org/src/commit/?id=f1ad4340e4adfbe9e64b4e2e9e9b19d87fa84eef
commit f1ad4340e4adfbe9e64b4e2e9e9b19d87fa84eef
Author: Konstantin Belousov <k...@freebsd.org>
AuthorDate: 2025-06-11 08:36:20 +0000
Commit: Konstantin Belousov <k...@freebsd.org>
CommitDate: 2025-06-12 20:32:26 +0000
vm/vm_mmap.c: provide extended errors for most places
Reviewed by: brooks
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D50792
---
sys/vm/vm_mmap.c | 103 +++++++++++++++++++++++++++++++++++++++++++------------
1 file changed, 81 insertions(+), 22 deletions(-)
diff --git a/sys/vm/vm_mmap.c b/sys/vm/vm_mmap.c
index 492233215d4b..8444a8cbf021 100644
--- a/sys/vm/vm_mmap.c
+++ b/sys/vm/vm_mmap.c
@@ -231,35 +231,53 @@ kern_mmap(struct thread *td, const struct mmap_req *mrp)
*/
if (!SV_CURPROC_FLAG(SV_AOUT)) {
if ((len == 0 && p->p_osrel >= P_OSREL_MAP_ANON) ||
- ((flags & MAP_ANON) != 0 && (fd != -1 || pos != 0)))
+ ((flags & MAP_ANON) != 0 && (fd != -1 || pos != 0))) {
+ SET_ERROR2(EINVAL,
+ "offset not zero/fd not -1 for MAP_ANON",
+ fd, pos);
return (EINVAL);
+ }
} else {
if ((flags & MAP_ANON) != 0)
pos = 0;
}
if (flags & MAP_STACK) {
- if ((fd != -1) ||
- ((prot & (PROT_READ | PROT_WRITE)) != (PROT_READ |
PROT_WRITE)))
+ if ((fd != -1) || ((prot & (PROT_READ | PROT_WRITE)) !=
+ (PROT_READ | PROT_WRITE))) {
+ SET_ERROR1(EINVAL, "MAP_STACK with prot < rw", prot);
return (EINVAL);
+ }
flags |= MAP_ANON;
pos = 0;
}
if ((flags & ~(MAP_SHARED | MAP_PRIVATE | MAP_FIXED | MAP_HASSEMAPHORE |
MAP_STACK | MAP_NOSYNC | MAP_ANON | MAP_EXCL | MAP_NOCORE |
- MAP_PREFAULT_READ | MAP_GUARD | MAP_32BIT | MAP_ALIGNMENT_MASK)) !=
0)
+ MAP_PREFAULT_READ | MAP_GUARD | MAP_32BIT |
+ MAP_ALIGNMENT_MASK)) != 0) {
+ SET_ERROR0(EINVAL, "reserved flag set");
return (EINVAL);
- if ((flags & (MAP_EXCL | MAP_FIXED)) == MAP_EXCL)
+ }
+ if ((flags & (MAP_EXCL | MAP_FIXED)) == MAP_EXCL) {
+ SET_ERROR0(EINVAL, "EXCL without FIXED");
return (EINVAL);
- if ((flags & (MAP_SHARED | MAP_PRIVATE)) == (MAP_SHARED | MAP_PRIVATE))
+ }
+ if ((flags & (MAP_SHARED | MAP_PRIVATE)) == (MAP_SHARED |
+ MAP_PRIVATE)) {
+ SET_ERROR0(EINVAL, "both SHARED and PRIVATE set");
return (EINVAL);
+ }
if (prot != PROT_NONE &&
- (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC)) != 0)
+ (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC)) != 0) {
+ SET_ERROR1(EINVAL, "invalid prot", prot);
return (EINVAL);
+ }
if ((flags & MAP_GUARD) != 0 && (prot != PROT_NONE || fd != -1 ||
pos != 0 || (flags & ~(MAP_FIXED | MAP_GUARD | MAP_EXCL |
- MAP_32BIT | MAP_ALIGNMENT_MASK)) != 0))
+ MAP_32BIT | MAP_ALIGNMENT_MASK)) != 0)) {
+ SET_ERROR0(EINVAL, "GUARD with wrong parameters");
return (EINVAL);
+ }
/*
* Align the file position to a page boundary,
@@ -279,8 +297,10 @@ kern_mmap(struct thread *td, const struct mmap_req *mrp)
align = flags & MAP_ALIGNMENT_MASK;
if (align != 0 && align != MAP_ALIGNED_SUPER &&
(align >> MAP_ALIGNMENT_SHIFT >= sizeof(void *) * NBBY ||
- align >> MAP_ALIGNMENT_SHIFT < PAGE_SHIFT))
+ align >> MAP_ALIGNMENT_SHIFT < PAGE_SHIFT)) {
+ SET_ERROR1(EINVAL, "bad alignment", align);
return (EINVAL);
+ }
/*
* Check for illegal addresses. Watch out for address wrap... Note
@@ -293,14 +313,21 @@ kern_mmap(struct thread *td, const struct mmap_req *mrp)
* should be aligned after adjustment by pageoff.
*/
addr -= pageoff;
- if (addr & PAGE_MASK)
+ if ((addr & PAGE_MASK) != 0) {
+ SET_ERROR1(EINVAL, "fixed mapping not aligned", addr);
return (EINVAL);
+ }
/* Address range must be all in user VM space. */
- if (!vm_map_range_valid(&vms->vm_map, addr, addr + size))
+ if (!vm_map_range_valid(&vms->vm_map, addr, addr + size)) {
+ SET_ERROR0(EINVAL, "mapping outside vm_map");
return (EINVAL);
- if (flags & MAP_32BIT && addr + size > MAP_32BIT_MAX_ADDR)
+ }
+ if (flags & MAP_32BIT && addr + size > MAP_32BIT_MAX_ADDR) {
+ SET_ERROR0(EINVAL,
+ "fixed 32bit mapping does not fit into 4G");
return (EINVAL);
+ }
} else if (flags & MAP_32BIT) {
/*
* For MAP_32BIT, override the hint if it is too high and
@@ -367,6 +394,7 @@ kern_mmap(struct thread *td, const struct mmap_req *mrp)
goto done;
if ((flags & (MAP_SHARED | MAP_PRIVATE)) == 0 &&
p->p_osrel >= P_OSREL_MAP_FSTRICT) {
+ SET_ERROR0(EINVAL, "neither SHARED nor PRIVATE req");
error = EINVAL;
goto done;
}
@@ -1296,6 +1324,7 @@ vm_mmap_vnode(struct thread *td, vm_size_t objsize,
vm_pager_update_writecount(obj, 0, objsize);
}
} else {
+ SET_ERROR0(EINVAL, "non-reg file");
error = EINVAL;
goto done;
}
@@ -1379,14 +1408,18 @@ vm_mmap_cdev(struct thread *td, vm_size_t objsize,
vm_prot_t prot,
*flagsp |= MAP_ANON;
return (0);
}
+
/*
* cdevs do not provide private mappings of any kind.
*/
if ((*maxprotp & VM_PROT_WRITE) == 0 &&
(prot & VM_PROT_WRITE) != 0)
return (EACCES);
- if (flags & (MAP_PRIVATE|MAP_COPY))
+ if ((flags & (MAP_PRIVATE | MAP_COPY)) != 0) {
+ SET_ERROR0(EINVAL, "cdev mapping must be shared");
return (EINVAL);
+ }
+
/*
* Force device mappings to be shared.
*/
@@ -1410,8 +1443,10 @@ vm_mmap_cdev(struct thread *td, vm_size_t objsize,
vm_prot_t prot,
return (error);
obj = vm_pager_allocate(OBJT_DEVICE, cdev, objsize, prot, *foff,
td->td_ucred);
- if (obj == NULL)
+ if (obj == NULL) {
+ SET_ERROR0(EINVAL, "cdev driver does not support mmap");
return (EINVAL);
+ }
*objp = obj;
*flagsp = flags;
return (0);
@@ -1428,8 +1463,10 @@ vm_mmap(vm_map_t map, vm_offset_t *addr, vm_size_t size,
vm_prot_t prot,
int error;
boolean_t writecounted;
- if (size == 0)
+ if (size == 0) {
+ SET_ERROR0(EINVAL, "zero-sized req");
return (EINVAL);
+ }
size = round_page(size);
object = NULL;
@@ -1455,6 +1492,7 @@ vm_mmap(vm_map_t map, vm_offset_t *addr, vm_size_t size,
vm_prot_t prot,
handle, &foff, &object, &writecounted);
break;
default:
+ SET_ERROR1(EINVAL, "unsupported backing obj type", handle_type);
error = EINVAL;
break;
}
@@ -1536,21 +1574,32 @@ vm_mmap_object(vm_map_t map, vm_offset_t *addr,
vm_size_t size, vm_prot_t prot,
* callbacks) and other internal mapping requests (such as in
* exec).
*/
- if (foff & PAGE_MASK)
+ if ((foff & PAGE_MASK) != 0) {
+ SET_ERROR1(EINVAL, "offset not page-aligned", foff);
return (EINVAL);
+ }
if ((flags & MAP_FIXED) == 0) {
fitit = true;
*addr = round_page(*addr);
} else {
- if (*addr != trunc_page(*addr))
+ if (*addr != trunc_page(*addr)) {
+ SET_ERROR1(EINVAL,
+ "non-fixed mapping address not aligned", *addr);
return (EINVAL);
+ }
fitit = false;
}
if (flags & MAP_ANON) {
- if (object != NULL || foff != 0)
+ if (object != NULL) {
+ SET_ERROR0(EINVAL, "anon mapping backed by an object");
+ return (EINVAL);
+ }
+ if (foff != 0) {
+ SET_ERROR0(EINVAL, "anon mapping with non-zero offset");
return (EINVAL);
+ }
docow = 0;
} else if (flags & MAP_PREFAULT_READ)
docow = MAP_PREFAULT;
@@ -1569,8 +1618,10 @@ vm_mmap_object(vm_map_t map, vm_offset_t *addr,
vm_size_t size, vm_prot_t prot,
if (writecounted)
docow |= MAP_WRITECOUNT;
if (flags & MAP_STACK) {
- if (object != NULL)
+ if (object != NULL) {
+ SET_ERROR0(EINVAL, "stack mapping backed by an object");
return (EINVAL);
+ }
docow |= MAP_STACK_AREA;
}
if ((flags & MAP_EXCL) != 0)
@@ -1632,16 +1683,24 @@ vm_mmap_object(vm_map_t map, vm_offset_t *addr,
vm_size_t size, vm_prot_t prot,
int
vm_mmap_to_errno(int rv)
{
+ int error;
switch (rv) {
case KERN_SUCCESS:
return (0);
case KERN_INVALID_ADDRESS:
case KERN_NO_SPACE:
- return (ENOMEM);
+ error = ENOMEM;
+ break;
case KERN_PROTECTION_FAILURE:
- return (EACCES);
+ error = EACCES;
+ break;
default:
- return (EINVAL);
+ error = EINVAL;
+ break;
}
+ if ((curthread->td_pflags2 & (TDP2_UEXTERR | TDP2_EXTERR)) ==
+ TDP2_UEXTERR)
+ SET_ERROR1(error, "mach error", rv);
+ return (error);
}
