On 11/16/2022 3:29 PM, Minsuk Kang wrote:
This patch fixes slab-out-of-bounds reads in brcmfmac that occur in brcmf_construct_chaninfo() and brcmf_enable_bw40_2g() when the count value of channel specifications provided by the device is greater than the length of 'list->element[]', decided by the size of the 'list' allocated with kzalloc(). The patch adds checks that make the functions free the buffer and return -EINVAL if that is the case. Note that the negative return is handled by the caller, brcmf_setup_wiphybands() or brcmf_cfg80211_attach(). Found by a modified version of syzkaller. Crash Report from brcmf_construct_chaninfo(): ================================================================== BUG: KASAN: slab-out-of-bounds in brcmf_setup_wiphybands+0x1238/0x1430 Read of size 4 at addr ffff888115f24600 by task kworker/0:2/1896 CPU: 0 PID: 1896 Comm: kworker/0:2 Tainted: G W O 5.14.0+ #132 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014 Workqueue: usb_hub_wq hub_event
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Reported-by: Dokyung Song <dokyungs@xxxxxxxxxxxx> Reported-by: Jisoo Jang <jisoo.jang@xxxxxxxxxxxx> Reported-by: Minsuk Kang <linuxlovemin@xxxxxxxxxxxx> Reviewed-by: Arend van Spriel <arend.vanspriel@xxxxxxxxxxxx>
My earlier review comment is addressed so I am okay with the patch as is. Regards, Arend
