mremap
Implemented in Antinomie 0.7.0 · Syscall list
Synopsis
Section titled “Synopsis”long mremap(unsigned long addr, unsigned long old_len, unsigned long new_len, unsigned long flags, unsigned long new_addr);| Number (x86-64) | 25 |
| ABI | common |
| Kernel entry point | sys_mremap |
This is the raw kernel prototype from the pinned Linux 6.12.94 schema, not the libc wrapper.
Description
Section titled “Description”Resizes or moves an existing memory mapping.
Arguments
Section titled “Arguments”| Name | Type | Meaning |
|---|---|---|
addr (arg0) |
unsigned long |
Memory or socket address, depending on the call. |
old_len (arg1) |
unsigned long |
Current size of the mapping. |
new_len (arg2) |
unsigned long |
Requested new size of the mapping. |
flags (arg3) |
unsigned long |
Option flags that change the behavior of the call. |
new_addr (arg4) |
unsigned long |
Requested new address. |
Return value
Section titled “Return value”On success: the new address of the mapping.
In an Antinomie trace the Return column and the ret filter field show the raw kernel return value. On failure that is the negative errno, for example -2 for ENOENT, not the -1 plus errno that the libc wrapper gives. syscall.errno holds the positive errno and syscall.success is false.
Common errors
Section titled “Common errors”| Raw return | Name | Meaning |
|---|---|---|
-14 |
EFAULT |
A pointer argument points outside the accessible address space. |
-22 |
EINVAL |
An argument is invalid. |
-12 |
ENOMEM |
The kernel is out of memory. |
Man page
Section titled “Man page”Captured by Antinomie
Section titled “Captured by Antinomie”Coverage mark: Implemented. All arguments are plain values, recorded as the raw argument words at entry. There is no pointee to copy and no known gap.
Every call is recorded as an Entry record (the six argument words and the pointees copied at entry) and an Exit record (the return value and the pointees copied at exit).
Arguments
Section titled “Arguments”| Argument | When | How | Recorded field key | Condition |
|---|---|---|---|---|
addr (arg0) |
Entry | raw scalar word | args.0, args.addr |
|
old_len (arg1) |
Entry | raw scalar word | args.1, args.old_len |
|
new_len (arg2) |
Entry | raw scalar word | args.2, args.new_len |
|
flags (arg3) |
Entry | raw scalar word; Syscall Trace also decodes it into flag names (mremap group), listing unknown bits separately |
args.3, args.flags |
|
new_addr (arg4) |
Entry | raw scalar word | args.4, args.new_addr |
Filter fields
Section titled “Filter fields”- Result:
ret,syscall.errno,syscall.success,syscall.duration_ns. - Argument words:
args.addr(arg0),args.old_len(arg1),args.new_len(arg2),args.flags(arg3),args.new_addr(arg4);args.0toargs.5by position.
See Syscall Trace filter for the full syntax.
For what the capture statuses mean, see Capture statuses. For what is never recorded, see Known gaps.