projects / thirdparty / kernel / stable-queue.git / blame
| Commit | Line | Data |
|---|---|---|
| 9659d8ac GKH |
1 | From b0cc58a25d04160d39a80e436847eaa2fbc5aa09 Mon Sep 17 00:00:00 2001 |
| 2 | From: Dan Carpenter <error27@gmail.com> | |
| 3 | Date: Tue, 6 Apr 2010 19:31:26 +0300 | |
| 4 | Subject: ALSA: mixart: range checking proc file | |
| 5 | ||
| 6 | From: Dan Carpenter <error27@gmail.com> | |
| 7 | ||
| 8 | commit b0cc58a25d04160d39a80e436847eaa2fbc5aa09 upstream. | |
| 9 | ||
| 10 | The original code doesn't take into consideration that the value of | |
| 11 | MIXART_BA0_SIZE - pos can be less than zero which would lead to a large | |
| 12 | unsigned value for "count". | |
| 13 | ||
| 14 | Also I moved the check that read size is a multiple of 4 bytes below | |
| 15 | the code that adjusts "count". | |
| 16 | ||
| 17 | Signed-off-by: Dan Carpenter <error27@gmail.com> | |
| 18 | Acked-by: Linus Torvalds <torvalds@linux-foundation.org> | |
| 19 | Signed-off-by: Takashi Iwai <tiwai@suse.de> | |
| 20 | Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> | |
| 21 | ||
| 22 | --- | |
| 23 | sound/pci/mixart/mixart.c | 24 ++++++++++++++---------- | |
| 24 | 1 file changed, 14 insertions(+), 10 deletions(-) | |
| 25 | ||
| 26 | --- a/sound/pci/mixart/mixart.c | |
| 27 | +++ b/sound/pci/mixart/mixart.c | |
| 28 | @@ -1161,13 +1161,15 @@ static long snd_mixart_BA0_read(struct s | |
| 29 | unsigned long count, unsigned long pos) | |
| 30 | { | |
| 31 | struct mixart_mgr *mgr = entry->private_data; | |
| 32 | + unsigned long maxsize; | |
| 33 | ||
| 34 | - count = count & ~3; /* make sure the read size is a multiple of 4 bytes */ | |
| 35 | - if(count <= 0) | |
| 36 | + if (pos >= MIXART_BA0_SIZE) | |
| 37 | return 0; | |
| 38 | - if(pos + count > MIXART_BA0_SIZE) | |
| 39 | - count = (long)(MIXART_BA0_SIZE - pos); | |
| 40 | - if(copy_to_user_fromio(buf, MIXART_MEM( mgr, pos ), count)) | |
| 41 | + maxsize = MIXART_BA0_SIZE - pos; | |
| 42 | + if (count > maxsize) | |
| 43 | + count = maxsize; | |
| 44 | + count = count & ~3; /* make sure the read size is a multiple of 4 bytes */ | |
| 45 | + if (copy_to_user_fromio(buf, MIXART_MEM(mgr, pos), count)) | |
| 46 | return -EFAULT; | |
| 47 | return count; | |
| 48 | } | |
| 49 | @@ -1180,13 +1182,15 @@ static long snd_mixart_BA1_read(struct s | |
| 50 | unsigned long count, unsigned long pos) | |
| 51 | { | |
| 52 | struct mixart_mgr *mgr = entry->private_data; | |
| 53 | + unsigned long maxsize; | |
| 54 | ||
| 55 | - count = count & ~3; /* make sure the read size is a multiple of 4 bytes */ | |
| 56 | - if(count <= 0) | |
| 57 | + if (pos > MIXART_BA1_SIZE) | |
| 58 | return 0; | |
| 59 | - if(pos + count > MIXART_BA1_SIZE) | |
| 60 | - count = (long)(MIXART_BA1_SIZE - pos); | |
| 61 | - if(copy_to_user_fromio(buf, MIXART_REG( mgr, pos ), count)) | |
| 62 | + maxsize = MIXART_BA1_SIZE - pos; | |
| 63 | + if (count > maxsize) | |
| 64 | + count = maxsize; | |
| 65 | + count = count & ~3; /* make sure the read size is a multiple of 4 bytes */ | |
| 66 | + if (copy_to_user_fromio(buf, MIXART_REG(mgr, pos), count)) | |
| 67 | return -EFAULT; | |
| 68 | return count; | |
| 69 | } |