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Diffstat (limited to 'docs/program_syntax.md')
| -rw-r--r-- | docs/program_syntax.md | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/docs/program_syntax.md b/docs/program_syntax.md index bf1775c4d..2b1fb3c0d 100644 --- a/docs/program_syntax.md +++ b/docs/program_syntax.md @@ -91,3 +91,25 @@ non-negative, a fault will be injected into the `N`-th occasion. r0 = openat$6lowpan_control(0xffffffffffffff9c, &(0x7f00000000c0), 0x2, 0x0) ioctl$LOOP_SET_FD(r0, 0x4c00, r0) (fail_nth: 5) ``` + +#### Async +Syntax: `async`. + +Instructs `syz-executor` not to wait until the call completes and +to proceed immediately to the next call. + +``` +r0 = openat(0xffffffffffffff9c, &AUTO='./file1\x00', 0x42, 0x1ff) +write(r0, &AUTO="01010101", 0x4) (async) +read(r0, &AUTO=""/4, 0x4) +close(r0) +``` + +When setting `async` flags be aware of the following considerations: +* Such programs should only be executed in threaded mode (i.e. `-threaded` +flag must be passed to `syz-executor`. +* Each `async` call is executed in a separate thread and there's a +limited number of available threads (`kMaxThreads = 16`). +* If an `async` call produces a resource, keep in mind that some other call +might take it as input and `syz-executor` will just pass 0 if the resource- +producing call has not finished by that time. |