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| author | Theodore Ts'o <tytso@mit.edu> | 2019-02-20 16:06:38 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-06-25 11:48:57 +0200 |
| commit | 915917713de00f0e1c22b9f68375ea1bc1ad4651 (patch) | |
| tree | e65cea2a4324dfcb0ade1f316655c4a49a4c43f5 /include/trace | |
| parent | 83bd6dae1035008709a80c861e857bbbfc5507e6 (diff) | |
| download | linux-stable-915917713de00f0e1c22b9f68375ea1bc1ad4651.tar.gz linux-stable-915917713de00f0e1c22b9f68375ea1bc1ad4651.tar.bz2 linux-stable-915917713de00f0e1c22b9f68375ea1bc1ad4651.zip | |
random: only read from /dev/random after its pool has received 128 bits
commit eb9d1bf079bb438d1a066d72337092935fc770f6 upstream.
Immediately after boot, we allow reads from /dev/random before its
entropy pool has been fully initialized. Fix this so that we don't
allow this until the blocking pool has received 128 bits.
We do this by repurposing the initialized flag in the entropy pool
struct, and use the initialized flag in the blocking pool to indicate
whether it is safe to pull from the blocking pool.
To do this, we needed to rework when we decide to push entropy from the
input pool to the blocking pool, since the initialized flag for the
input pool was used for this purpose. To simplify things, we no
longer use the initialized flag for that purpose, nor do we use the
entropy_total field any more.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/trace')
| -rw-r--r-- | include/trace/events/random.h | 13 |
1 files changed, 5 insertions, 8 deletions
diff --git a/include/trace/events/random.h b/include/trace/events/random.h index 0560dfc33f1c..32c10a515e2d 100644 --- a/include/trace/events/random.h +++ b/include/trace/events/random.h @@ -62,15 +62,14 @@ DEFINE_EVENT(random__mix_pool_bytes, mix_pool_bytes_nolock, TRACE_EVENT(credit_entropy_bits, TP_PROTO(const char *pool_name, int bits, int entropy_count, - int entropy_total, unsigned long IP), + unsigned long IP), - TP_ARGS(pool_name, bits, entropy_count, entropy_total, IP), + TP_ARGS(pool_name, bits, entropy_count, IP), TP_STRUCT__entry( __field( const char *, pool_name ) __field( int, bits ) __field( int, entropy_count ) - __field( int, entropy_total ) __field(unsigned long, IP ) ), @@ -78,14 +77,12 @@ TRACE_EVENT(credit_entropy_bits, __entry->pool_name = pool_name; __entry->bits = bits; __entry->entropy_count = entropy_count; - __entry->entropy_total = entropy_total; __entry->IP = IP; ), - TP_printk("%s pool: bits %d entropy_count %d entropy_total %d " - "caller %pS", __entry->pool_name, __entry->bits, - __entry->entropy_count, __entry->entropy_total, - (void *)__entry->IP) + TP_printk("%s pool: bits %d entropy_count %d caller %pS", + __entry->pool_name, __entry->bits, + __entry->entropy_count, (void *)__entry->IP) ); TRACE_EVENT(push_to_pool, |