Messages in this thread |  | | Date | Thu, 4 Apr 2024 15:22:35 +0200 | | From | Greg KH <> | | Subject | Re: [PATCH v2] usb: typec: tcpm: Correct the PDO counting in pd_set |
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On Tue, Mar 26, 2024 at 11:19:09PM +0800, Kyle Tso wrote: > Off-by-one errors happen because nr_snk_pdo and nr_src_pdo are > incorrectly added one. The index of the loop is equal to the number of > PDOs to be updated when leaving the loop and it doesn't need to be added > one. > > When doing the power negotiation, TCPM relies on the "nr_snk_pdo" as > the size of the local sink PDO array to match the Source capabilities > of the partner port. If the off-by-one overflow occurs, a wrong RDO > might be sent and unexpected power transfer might happen such as over > voltage or over current (than expected). > > "nr_src_pdo" is used to set the Rp level when the port is in Source > role. It is also the array size of the local Source capabilities when > filling up the buffer which will be sent as the Source PDOs (such as > in Power Negotiation). If the off-by-one overflow occurs, a wrong Rp > level might be set and wrong Source PDOs will be sent to the partner > port. This could potentially cause over current or port resets. > > Fixes: cd099cde4ed2 ("usb: typec: tcpm: Support multiple capabilities") > Cc: stable@vger.kernel.org > Signed-off-by: Kyle Tso <kyletso@google.com> > --- > v1 -> v2: > - update the commit message (adding the problems this patch solves) > > drivers/usb/typec/tcpm/tcpm.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-)
This fails to apply to my usb-linus branch :(
Can you rebase and resend?
thanks,
greg k-h
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