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author | Dan Rosenberg <drosenberg@vsecurity.com> | 2011-03-23 10:53:41 -0400 |
---|---|---|
committer | Takashi Iwai <tiwai@suse.de> | 2011-03-23 22:47:46 +0100 |
commit | b769f49463711205d57286e64cf535ed4daf59e9 (patch) | |
tree | 1c674fdbed533434d2ba9b7b1b3646243160e55c /sound/oss/sequencer.c | |
parent | ce24f58a1187ca3058d72c3f897e3b574209ab20 (diff) | |
download | op-kernel-dev-b769f49463711205d57286e64cf535ed4daf59e9.zip op-kernel-dev-b769f49463711205d57286e64cf535ed4daf59e9.tar.gz |
sound/oss: remove offset from load_patch callbacks
Was: [PATCH] sound/oss/midi_synth: prevent underflow, use of
uninitialized value, and signedness issue
The offset passed to midi_synth_load_patch() can be essentially
arbitrary. If it's greater than the header length, this will result in
a copy_from_user(dst, src, negative_val). While this will just return
-EFAULT on x86, on other architectures this may cause memory corruption.
Additionally, the length field of the sysex_info structure may not be
initialized prior to its use. Finally, a signed comparison may result
in an unintentionally large loop.
On suggestion by Takashi Iwai, version two removes the offset argument
from the load_patch callbacks entirely, which also resolves similar
issues in opl3. Compile tested only.
v3 adjusts comments and hopefully gets copy offsets right.
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/oss/sequencer.c')
-rw-r--r-- | sound/oss/sequencer.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/sound/oss/sequencer.c b/sound/oss/sequencer.c index 5ea1098..30bcfe4 100644 --- a/sound/oss/sequencer.c +++ b/sound/oss/sequencer.c @@ -241,7 +241,7 @@ int sequencer_write(int dev, struct file *file, const char __user *buf, int coun return -ENXIO; fmt = (*(short *) &event_rec[0]) & 0xffff; - err = synth_devs[dev]->load_patch(dev, fmt, buf, p + 4, c, 0); + err = synth_devs[dev]->load_patch(dev, fmt, buf + p, c, 0); if (err < 0) return err; |