New function that rejects unsupported map types and flags.
In 4b840f96 we should not have accepted MAP_SHARED_VALIDATE
without actually validating the rest of the flags.
Fixes: 4b840f96 ("linux-user: Populate more bits in mmap_flags_tbl")
Reviewed-by: Alex Bennée <alex.ben...@linaro.org>
Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
---
linux-user/syscall.c | 90 +++++++++++++++++++++++++++++++++++---------
1 file changed, 73 insertions(+), 17 deletions(-)
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index a15bce2be2..34deff0723 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -5985,10 +5985,6 @@ static const StructEntry struct_termios_def = {
#endif
static const bitmask_transtbl mmap_flags_tbl[] = {
- { TARGET_MAP_TYPE, TARGET_MAP_SHARED, MAP_TYPE, MAP_SHARED },
- { TARGET_MAP_TYPE, TARGET_MAP_PRIVATE, MAP_TYPE, MAP_PRIVATE },
- { TARGET_MAP_TYPE, TARGET_MAP_SHARED_VALIDATE,
- MAP_TYPE, MAP_SHARED_VALIDATE },
{ TARGET_MAP_FIXED, TARGET_MAP_FIXED, MAP_FIXED, MAP_FIXED },
{ TARGET_MAP_ANONYMOUS, TARGET_MAP_ANONYMOUS,
MAP_ANONYMOUS, MAP_ANONYMOUS },
@@ -6006,7 +6002,6 @@ static const bitmask_transtbl mmap_flags_tbl[] = {
Recognize it for the target insofar as we do not want to pass
it through to the host. */
{ TARGET_MAP_STACK, TARGET_MAP_STACK, 0, 0 },
- { TARGET_MAP_SYNC, TARGET_MAP_SYNC, MAP_SYNC, MAP_SYNC },
{ TARGET_MAP_NONBLOCK, TARGET_MAP_NONBLOCK, MAP_NONBLOCK, MAP_NONBLOCK },
{ TARGET_MAP_POPULATE, TARGET_MAP_POPULATE, MAP_POPULATE, MAP_POPULATE },
{ TARGET_MAP_FIXED_NOREPLACE, TARGET_MAP_FIXED_NOREPLACE,
@@ -6016,6 +6011,75 @@ static const bitmask_transtbl mmap_flags_tbl[] = {
{ 0, 0, 0, 0 }
};
+/*
+ * Arrange for legacy / undefined architecture specific flags to be
+ * ignored by mmap handling code.
+ */
+#ifndef TARGET_MAP_32BIT
+#define TARGET_MAP_32BIT 0
+#endif
+#ifndef TARGET_MAP_HUGE_2MB
+#define TARGET_MAP_HUGE_2MB 0
+#endif
+#ifndef TARGET_MAP_HUGE_1GB
+#define TARGET_MAP_HUGE_1GB 0
+#endif
+
+static abi_long do_mmap(abi_ulong addr, abi_ulong len, int prot,
+ int target_flags, int fd, off_t offset)
+{
+ /*
+ * The historical set of flags that all mmap types implicitly support.
+ */
+ enum {
+ TARGET_LEGACY_MAP_MASK = TARGET_MAP_SHARED
+ | TARGET_MAP_PRIVATE
+ | TARGET_MAP_FIXED
+ | TARGET_MAP_ANONYMOUS
+ | TARGET_MAP_DENYWRITE
+ | TARGET_MAP_EXECUTABLE
+ | TARGET_MAP_UNINITIALIZED
+ | TARGET_MAP_GROWSDOWN
+ | TARGET_MAP_LOCKED
+ | TARGET_MAP_NORESERVE
+ | TARGET_MAP_POPULATE
+ | TARGET_MAP_NONBLOCK
+ | TARGET_MAP_STACK
+ | TARGET_MAP_HUGETLB
+ | TARGET_MAP_32BIT
+ | TARGET_MAP_HUGE_2MB
+ | TARGET_MAP_HUGE_1GB
+ };
+ int host_flags;
+
+ switch (target_flags & TARGET_MAP_TYPE) {
+ case TARGET_MAP_PRIVATE:
+ host_flags = MAP_PRIVATE;
+ break;
+ case TARGET_MAP_SHARED:
+ host_flags = MAP_SHARED;
+ break;
+ case TARGET_MAP_SHARED_VALIDATE:
+ /*
+ * MAP_SYNC is only supported for MAP_SHARED_VALIDATE, and is
+ * therefore omitted from mmap_flags_tbl and TARGET_LEGACY_MAP_MASK.
+ */
+ if (target_flags & ~(TARGET_LEGACY_MAP_MASK | TARGET_MAP_SYNC)) {
+ return -TARGET_EOPNOTSUPP;
+ }
+ host_flags = MAP_SHARED_VALIDATE;
+ if (target_flags & TARGET_MAP_SYNC) {
+ host_flags |= MAP_SYNC;
+ }
+ break;
+ default:
+ return -TARGET_EINVAL;
+ }
+ host_flags |= target_to_host_bitmask(target_flags, mmap_flags_tbl);
+
+ return get_errno(target_mmap(addr, len, prot, host_flags, fd, offset));
+}
+
/*
* NOTE: TARGET_ABI32 is defined for TARGET_I386 (but not for TARGET_X86_64)
* TARGET_I386 is defined if TARGET_X86_64 is defined
@@ -10536,28 +10600,20 @@ static abi_long do_syscall1(CPUArchState *cpu_env,
int num, abi_long arg1,
v5 = tswapal(v[4]);
v6 = tswapal(v[5]);
unlock_user(v, arg1, 0);
- ret = get_errno(target_mmap(v1, v2, v3,
- target_to_host_bitmask(v4,
mmap_flags_tbl),
- v5, v6));
+ return do_mmap(v1, v2, v3, v4, v5, v6);
}
#else
/* mmap pointers are always untagged */
- ret = get_errno(target_mmap(arg1, arg2, arg3,
- target_to_host_bitmask(arg4,
mmap_flags_tbl),
- arg5,
- arg6));
+ return do_mmap(arg1, arg2, arg3, arg4, arg5, arg6);
#endif
- return ret;
#endif
#ifdef TARGET_NR_mmap2
case TARGET_NR_mmap2:
#ifndef MMAP_SHIFT
#define MMAP_SHIFT 12
#endif
- ret = target_mmap(arg1, arg2, arg3,
- target_to_host_bitmask(arg4, mmap_flags_tbl),
- arg5, (off_t)(abi_ulong)arg6 << MMAP_SHIFT);
- return get_errno(ret);
+ return do_mmap(arg1, arg2, arg3, arg4, arg5,
+ (off_t)(abi_ulong)arg6 << MMAP_SHIFT);
#endif
case TARGET_NR_munmap:
arg1 = cpu_untagged_addr(cpu, arg1);
--
2.34.1
