diff options
| -rw-r--r-- | share/man/man5/core.5 | 16 | ||||
| -rw-r--r-- | sys/kern/kern_exec.c | 7 |
2 files changed, 22 insertions, 1 deletions
diff --git a/share/man/man5/core.5 b/share/man/man5/core.5 index d176548d1570..0af1b2b7e8bf 100644 --- a/share/man/man5/core.5 +++ b/share/man/man5/core.5 @@ -28,7 +28,7 @@ .\" @(#)core.5 8.3 (Berkeley) 12/11/93 .\" $FreeBSD$ .\" -.Dd August 2, 2020 +.Dd October 5, 2021 .Dt CORE 5 .Os .Sh NAME @@ -57,6 +57,20 @@ The maximum size of a core file is limited by the limit. Files which would be larger than the limit are not created. .Pp +With a large limit, a process that had mapped a very large, +and perhaps sparsely populated, virtual memory region, could take +a very long time to create core dumps. +The system ignores all signals sent to a process writing a core file, except +.Dv SIGKILL +which terminates the writing and causes immediate exit of the process. +The behavior of +.Dv SIGKILL +can be disabled by setting tunable +.Xr sysctl 8 +variable +.Va kern.core_dump_can_intr +to zero. +.Pp The name of the file is controlled via the .Xr sysctl 8 variable diff --git a/sys/kern/kern_exec.c b/sys/kern/kern_exec.c index 4b3035cb7e08..7ec405ee6a62 100644 --- a/sys/kern/kern_exec.c +++ b/sys/kern/kern_exec.c @@ -151,6 +151,11 @@ static int map_at_zero = 0; SYSCTL_INT(_security_bsd, OID_AUTO, map_at_zero, CTLFLAG_RWTUN, &map_at_zero, 0, "Permit processes to map an object at virtual address 0."); +static int core_dump_can_intr = 1; +SYSCTL_INT(_kern, OID_AUTO, core_dump_can_intr, CTLFLAG_RWTUN, + &core_dump_can_intr, 0, + "Core dumping interruptible with SIGKILL"); + static int sysctl_kern_ps_strings(SYSCTL_HANDLER_ARGS) { @@ -1943,6 +1948,8 @@ core_output(char *base, size_t len, off_t offset, struct coredump_params *cp, * anonymous memory or truncated files, for example. */ for (runlen = 0; runlen < len; runlen += PAGE_SIZE) { + if (core_dump_can_intr && curproc_sigkilled()) + return (EINTR); error = vm_fault(map, (uintptr_t)base + runlen, VM_PROT_READ, VM_FAULT_NOFILL, NULL); if (runlen == 0) |