diff options
| author | cinap_lenrek <cinap_lenrek@felloff.net> | 2023-04-08 20:30:47 +0000 |
|---|---|---|
| committer | cinap_lenrek <cinap_lenrek@felloff.net> | 2023-04-08 20:30:47 +0000 |
| commit | 60b1a2f82dc96b254d6dec1bfd1c14ca056c21dd (patch) | |
| tree | 1de5c2c26d7f7d0a0def0bbe4c11971a12735730 /sys/src/9/port/alloc.c | |
| parent | bd43bd6f1ae1b1ec7ee6873d9fd6766b049802e9 (diff) | |
kernel: Clear secrets on reboot
The idea is that when we reboot, we zero out
memory written by processes that have the private
flag set (such as factotum and keyfs), and also
clear the secrmem pool, which contains TLS keys
and the state of the random number generator.
This is so the newly booted kernel or firmware
will not find these secret keys in memory.
Diffstat (limited to 'sys/src/9/port/alloc.c')
| -rw-r--r-- | sys/src/9/port/alloc.c | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/sys/src/9/port/alloc.c b/sys/src/9/port/alloc.c index 6c3519fdf..70ea42a15 100644 --- a/sys/src/9/port/alloc.c +++ b/sys/src/9/port/alloc.c @@ -171,7 +171,7 @@ mallocsummary(void) /* non tracing * enum { - Npadlong = 0, + Npadlong = 0, MallocOffset = 0, ReallocOffset = 0, }; @@ -180,7 +180,7 @@ enum { /* tracing */ enum { - Npadlong = 2, + Npadlong = 2, MallocOffset = 0, ReallocOffset = 1 }; @@ -228,12 +228,14 @@ mallocz(ulong size, int clr) void *v; v = poolalloc(mainmem, size+Npadlong*sizeof(ulong)); - if(Npadlong && v != nil){ + if(v == nil) + return nil; + if(Npadlong){ v = (ulong*)v+Npadlong; setmalloctag(v, getcallerpc(&size)); setrealloctag(v, 0); } - if(clr && v != nil) + if(clr) memset(v, 0, size); return v; } @@ -244,13 +246,14 @@ mallocalign(ulong size, ulong align, long offset, ulong span) void *v; v = poolallocalign(mainmem, size+Npadlong*sizeof(ulong), align, offset-Npadlong*sizeof(ulong), span); - if(Npadlong && v != nil){ + if(v == nil) + return nil; + if(Npadlong){ v = (ulong*)v+Npadlong; setmalloctag(v, getcallerpc(&size)); setrealloctag(v, 0); } - if(v) - memset(v, 0, size); + memset(v, 0, size); return v; } @@ -268,10 +271,10 @@ realloc(void *v, ulong size) if(v != nil) v = (ulong*)v-Npadlong; - if(Npadlong !=0 && size != 0) + if(Npadlong && size != 0) size += Npadlong*sizeof(ulong); - - if(nv = poolrealloc(mainmem, v, size)){ + nv = poolrealloc(mainmem, v, size); + if(nv != nil){ nv = (ulong*)nv+Npadlong; setrealloctag(nv, getcallerpc(&v)); if(v == nil) |