diff options
| -rw-r--r-- | ChangeLog.txt | 4 | ||||
| -rw-r--r-- | ports/linux/pseudo_wrappers.c | 17 |
2 files changed, 12 insertions, 9 deletions
diff --git a/ChangeLog.txt b/ChangeLog.txt index f984820..41aeb9f 100644 --- a/ChangeLog.txt +++ b/ChangeLog.txt @@ -4,6 +4,10 @@ whether an error occurred, even if no call has returned a status indicating an error, and this is completely wrong but we can't fix them all. + * (seebs) check for wrapper initialization in syscall wrapper, + because what if it was the *first* call someone made. (Thanks + to Joshua Watt <jpewhacker@gmail.com> for diagnosing this + before I got a chance.) 2018-03-30: * (seebs) fix path stuff more thoroughly. diff --git a/ports/linux/pseudo_wrappers.c b/ports/linux/pseudo_wrappers.c index 229b1d9..6a76632 100644 --- a/ports/linux/pseudo_wrappers.c +++ b/ports/linux/pseudo_wrappers.c @@ -52,14 +52,13 @@ int pseudo_capset(cap_user_header_t hdrp, const cap_user_data_t datap) { long syscall(long number, ...) { - /* In a fit of optimism, I imagine that if we didn't get at least 7 - * arguments, reading past the ones we did get will read into this - * space and maybe not clash with or overlap with any later-declared - * values. This isn't really a guarantee, and is probably just - * superstition. - */ - unsigned long long padding[7]; - (void) padding; + long rc = -1; + + if (!pseudo_check_wrappers() || !real_syscall) { + /* rc was initialized to the "failure" value */ + pseudo_enosys("syscall"); + return rc; + } #ifdef SYS_renameat2 /* concerns exist about trying to parse arguments because syscall(2) @@ -78,7 +77,7 @@ syscall(long number, ...) { * guess about the number of args; the docs discuss calling conventions * up to 7, so let's try that? */ - void *res = __builtin_apply((void (*)()) real_syscall, __builtin_apply_args(), sizeof(long long) * 7); + void *res = __builtin_apply((void (*)()) real_syscall, __builtin_apply_args(), sizeof(long) * 7); __builtin_return(res); } |