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| author | Takashi Iwai <tiwai@suse.de> | 2018-11-23 15:44:00 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-12-05 19:32:08 +0100 |
| commit | b77c35ef8e38d9c4027f00a333ca139c583f2a18 (patch) | |
| tree | f04ef6f9a038e5949efb71047137359b13a89ff6 /kernel/trace/trace_functions_graph.c | |
| parent | e83c4405ebf02151daea8ce6da3bb74b34efcd6c (diff) | |
ALSA: ac97: Fix incorrect bit shift at AC97-SPSA control write
commit 7194eda1ba0872d917faf3b322540b4f57f11ba5 upstream.
The function snd_ac97_put_spsa() gets the bit shift value from the
associated private_value, but it extracts too much; the current code
extracts 8 bit values in bits 8-15, but this is a combination of two
nibbles (bits 8-11 and bits 12-15) for left and right shifts.
Due to the incorrect bits extraction, the actual shift may go beyond
the 32bit value, as spotted recently by UBSAN check:
UBSAN: Undefined behaviour in sound/pci/ac97/ac97_codec.c:836:7
shift exponent 68 is too large for 32-bit type 'int'
This patch fixes the shift value extraction by masking the properly
with 0x0f instead of 0xff.
Reported-and-tested-by: Meelis Roos <mroos@linux.ee>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel/trace/trace_functions_graph.c')
0 files changed, 0 insertions, 0 deletions