openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

char: hpet: Fix out-of-bounds read bug 

Currently, there is an out-of-bounds read on array hpetp->hp_dev
in the following for loop:

870         for (i = 0; i < hdp->hd_nirqs; i++)
871                 hpetp->hp_dev[i].hd_hdwirq = hdp->hd_irq[i];

This is due to the recent change from one-element array to
flexible-array member in struct hpets:

104 struct hpets {
	...
113         struct hpet_dev hp_dev[];
114 };

This change affected the total size of the dynamic memory
allocation, decreasing it by one time the size of struct hpet_dev.

Fix this by adjusting the allocation size when calling
struct_size().

Fixes: 987f028b86 ("char: hpet: Use flexible-array member")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Eric Biggers <ebiggers@kernel.org>
Link: https://lore.kernel.org/r/20200129022613.GA24281@embeddedor.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Gustavo A. R. Silva 2020-01-28 20:26:13 -06:00 committed by Greg Kroah-Hartman
parent 15d6632496
commit 98c49f1746
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/char/hpet.c
View File

@ -855,7 +855,7 @@ int hpet_alloc(struct hpet_data *hdp)
return 0;
}
hpetp = kzalloc(struct_size(hpetp, hp_dev, hdp->hd_nirqs - 1),
hpetp = kzalloc(struct_size(hpetp, hp_dev, hdp->hd_nirqs),
GFP_KERNEL);
if (!hpetp)