This is a note to let you know that I've just added the patch titled

xhci: fix unsafe memory usage in xhci tracing

to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-testing branch.

The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)

The patch will be merged to the usb-next branch sometime soon, after it passes testing, and the merge window is open.

If you have any questions about this process, please let me know.

From cbf286e8ef8337308c259ff5b9ce2e74d403be5a Mon Sep 17 00:00:00 2001

From: Mathias Nyman mathias.nyman@linux.intel.com Date: Fri, 20 Aug 2021 15:34:58 +0300 Subject: xhci: fix unsafe memory usage in xhci tracing

Removes static char buffer usage in the following decode functions: xhci_decode_trb() xhci_decode_ptortsc()

Caller must provide a buffer to use. In tracing use __get_str() as recommended to pass buffer.

Minor chanes are needed in xhci debugfs code as these functions are also used there. Changes include moving XHCI_MSG_MAX definititon from xhci-trace.h to xhci.h

Cc: stable@vger.kernel.org Signed-off-by: Mathias Nyman mathias.nyman@linux.intel.com Link: https://lore.kernel.org/r/20210820123503.2605901-2-mathias.nyman@linux.intel... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/host/xhci-debugfs.c | 6 ++-- drivers/usb/host/xhci-trace.h | 8 ++--- drivers/usb/host/xhci.h | 52 ++++++++++++++++++--------------- 3 files changed, 36 insertions(+), 30 deletions(-)

diff --git a/drivers/usb/host/xhci-debugfs.c b/drivers/usb/host/xhci-debugfs.c index 2c0fda57869e..85c12f56b17c 100644 --- a/drivers/usb/host/xhci-debugfs.c +++ b/drivers/usb/host/xhci-debugfs.c @@ -198,12 +198,13 @@ static void xhci_ring_dump_segment(struct seq_file *s, int i; dma_addr_t dma; union xhci_trb *trb; + char str[XHCI_MSG_MAX];

for (i = 0; i < TRBS_PER_SEGMENT; i++) { trb = &seg->trbs[i]; dma = seg->dma + i * sizeof(*trb); seq_printf(s, "%pad: %s\n", &dma, - xhci_decode_trb(le32_to_cpu(trb->generic.field[0]), + xhci_decode_trb(str, XHCI_MSG_MAX, le32_to_cpu(trb->generic.field[0]), le32_to_cpu(trb->generic.field[1]), le32_to_cpu(trb->generic.field[2]), le32_to_cpu(trb->generic.field[3]))); @@ -341,9 +342,10 @@ static int xhci_portsc_show(struct seq_file *s, void *unused) { struct xhci_port *port = s->private; u32 portsc; + char str[XHCI_MSG_MAX];

portsc = readl(port->addr); - seq_printf(s, "%s\n", xhci_decode_portsc(portsc)); + seq_printf(s, "%s\n", xhci_decode_portsc(str, portsc));

return 0; } diff --git a/drivers/usb/host/xhci-trace.h b/drivers/usb/host/xhci-trace.h index 627abd236dbe..5e1c50cb7016 100644 --- a/drivers/usb/host/xhci-trace.h +++ b/drivers/usb/host/xhci-trace.h @@ -25,8 +25,6 @@ #include "xhci.h" #include "xhci-dbgcap.h"

-#define XHCI_MSG_MAX 500 - DECLARE_EVENT_CLASS(xhci_log_msg, TP_PROTO(struct va_format *vaf), TP_ARGS(vaf), @@ -122,6 +120,7 @@ DECLARE_EVENT_CLASS(xhci_log_trb, __field(u32, field1) __field(u32, field2) __field(u32, field3) + __dynamic_array(char, str, XHCI_MSG_MAX) ), TP_fast_assign( __entry->type = ring->type; @@ -131,7 +130,7 @@ DECLARE_EVENT_CLASS(xhci_log_trb, __entry->field3 = le32_to_cpu(trb->field[3]); ), TP_printk("%s: %s", xhci_ring_type_string(__entry->type), - xhci_decode_trb(__entry->field0, __entry->field1, + xhci_decode_trb(__get_str(str), XHCI_MSG_MAX, __entry->field0, __entry->field1, __entry->field2, __entry->field3) ) ); @@ -523,6 +522,7 @@ DECLARE_EVENT_CLASS(xhci_log_portsc, TP_STRUCT__entry( __field(u32, portnum) __field(u32, portsc) + __dynamic_array(char, str, XHCI_MSG_MAX) ), TP_fast_assign( __entry->portnum = portnum; @@ -530,7 +530,7 @@ DECLARE_EVENT_CLASS(xhci_log_portsc, ), TP_printk("port-%d: %s", __entry->portnum, - xhci_decode_portsc(__entry->portsc) + xhci_decode_portsc(__get_str(str), __entry->portsc) ) );

diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index 3c7d281672ae..99ae9994f5eb 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -22,6 +22,9 @@ #include "xhci-ext-caps.h" #include "pci-quirks.h"

+/* max buffer size for trace and debug messages */ +#define XHCI_MSG_MAX 500 + /* xHCI PCI Configuration Registers */ #define XHCI_SBRN_OFFSET (0x60)

@@ -2235,15 +2238,14 @@ static inline char *xhci_slot_state_string(u32 state) } }

-static inline const char *xhci_decode_trb(u32 field0, u32 field1, u32 field2, - u32 field3) +static inline const char *xhci_decode_trb(char *str, size_t size, + u32 field0, u32 field1, u32 field2, u32 field3) { - static char str[256]; int type = TRB_FIELD_TO_TYPE(field3);

switch (type) { case TRB_LINK: - sprintf(str, + snprintf(str, size, "LINK %08x%08x intr %d type '%s' flags %c:%c:%c:%c", field1, field0, GET_INTR_TARGET(field2), xhci_trb_type_string(type), @@ -2260,7 +2262,7 @@ static inline const char *xhci_decode_trb(u32 field0, u32 field1, u32 field2, case TRB_HC_EVENT: case TRB_DEV_NOTE: case TRB_MFINDEX_WRAP: - sprintf(str, + snprintf(str, size, "TRB %08x%08x status '%s' len %d slot %d ep %d type '%s' flags %c:%c", field1, field0, xhci_trb_comp_code_string(GET_COMP_CODE(field2)), @@ -2273,7 +2275,8 @@ static inline const char *xhci_decode_trb(u32 field0, u32 field1, u32 field2,

break; case TRB_SETUP: - sprintf(str, "bRequestType %02x bRequest %02x wValue %02x%02x wIndex %02x%02x wLength %d length %d TD size %d intr %d type '%s' flags %c:%c:%c", + snprintf(str, size, + "bRequestType %02x bRequest %02x wValue %02x%02x wIndex %02x%02x wLength %d length %d TD size %d intr %d type '%s' flags %c:%c:%c", field0 & 0xff, (field0 & 0xff00) >> 8, (field0 & 0xff000000) >> 24, @@ -2290,7 +2293,8 @@ static inline const char *xhci_decode_trb(u32 field0, u32 field1, u32 field2, field3 & TRB_CYCLE ? 'C' : 'c'); break; case TRB_DATA: - sprintf(str, "Buffer %08x%08x length %d TD size %d intr %d type '%s' flags %c:%c:%c:%c:%c:%c:%c", + snprintf(str, size, + "Buffer %08x%08x length %d TD size %d intr %d type '%s' flags %c:%c:%c:%c:%c:%c:%c", field1, field0, TRB_LEN(field2), GET_TD_SIZE(field2), GET_INTR_TARGET(field2), xhci_trb_type_string(type), @@ -2303,7 +2307,8 @@ static inline const char *xhci_decode_trb(u32 field0, u32 field1, u32 field2, field3 & TRB_CYCLE ? 'C' : 'c'); break; case TRB_STATUS: - sprintf(str, "Buffer %08x%08x length %d TD size %d intr %d type '%s' flags %c:%c:%c:%c", + snprintf(str, size, + "Buffer %08x%08x length %d TD size %d intr %d type '%s' flags %c:%c:%c:%c", field1, field0, TRB_LEN(field2), GET_TD_SIZE(field2), GET_INTR_TARGET(field2), xhci_trb_type_string(type), @@ -2316,7 +2321,7 @@ static inline const char *xhci_decode_trb(u32 field0, u32 field1, u32 field2, case TRB_ISOC: case TRB_EVENT_DATA: case TRB_TR_NOOP: - sprintf(str, + snprintf(str, size, "Buffer %08x%08x length %d TD size %d intr %d type '%s' flags %c:%c:%c:%c:%c:%c:%c:%c", field1, field0, TRB_LEN(field2), GET_TD_SIZE(field2), GET_INTR_TARGET(field2), @@ -2333,21 +2338,21 @@ static inline const char *xhci_decode_trb(u32 field0, u32 field1, u32 field2,

case TRB_CMD_NOOP: case TRB_ENABLE_SLOT: - sprintf(str, + snprintf(str, size, "%s: flags %c", xhci_trb_type_string(type), field3 & TRB_CYCLE ? 'C' : 'c'); break; case TRB_DISABLE_SLOT: case TRB_NEG_BANDWIDTH: - sprintf(str, + snprintf(str, size, "%s: slot %d flags %c", xhci_trb_type_string(type), TRB_TO_SLOT_ID(field3), field3 & TRB_CYCLE ? 'C' : 'c'); break; case TRB_ADDR_DEV: - sprintf(str, + snprintf(str, size, "%s: ctx %08x%08x slot %d flags %c:%c", xhci_trb_type_string(type), field1, field0, @@ -2356,7 +2361,7 @@ static inline const char *xhci_decode_trb(u32 field0, u32 field1, u32 field2, field3 & TRB_CYCLE ? 'C' : 'c'); break; case TRB_CONFIG_EP: - sprintf(str, + snprintf(str, size, "%s: ctx %08x%08x slot %d flags %c:%c", xhci_trb_type_string(type), field1, field0, @@ -2365,7 +2370,7 @@ static inline const char *xhci_decode_trb(u32 field0, u32 field1, u32 field2, field3 & TRB_CYCLE ? 'C' : 'c'); break; case TRB_EVAL_CONTEXT: - sprintf(str, + snprintf(str, size, "%s: ctx %08x%08x slot %d flags %c", xhci_trb_type_string(type), field1, field0, @@ -2373,7 +2378,7 @@ static inline const char *xhci_decode_trb(u32 field0, u32 field1, u32 field2, field3 & TRB_CYCLE ? 'C' : 'c'); break; case TRB_RESET_EP: - sprintf(str, + snprintf(str, size, "%s: ctx %08x%08x slot %d ep %d flags %c:%c", xhci_trb_type_string(type), field1, field0, @@ -2394,7 +2399,7 @@ static inline const char *xhci_decode_trb(u32 field0, u32 field1, u32 field2, field3 & TRB_CYCLE ? 'C' : 'c'); break; case TRB_SET_DEQ: - sprintf(str, + snprintf(str, size, "%s: deq %08x%08x stream %d slot %d ep %d flags %c", xhci_trb_type_string(type), field1, field0, @@ -2405,14 +2410,14 @@ static inline const char *xhci_decode_trb(u32 field0, u32 field1, u32 field2, field3 & TRB_CYCLE ? 'C' : 'c'); break; case TRB_RESET_DEV: - sprintf(str, + snprintf(str, size, "%s: slot %d flags %c", xhci_trb_type_string(type), TRB_TO_SLOT_ID(field3), field3 & TRB_CYCLE ? 'C' : 'c'); break; case TRB_FORCE_EVENT: - sprintf(str, + snprintf(str, size, "%s: event %08x%08x vf intr %d vf id %d flags %c", xhci_trb_type_string(type), field1, field0, @@ -2421,14 +2426,14 @@ static inline const char *xhci_decode_trb(u32 field0, u32 field1, u32 field2, field3 & TRB_CYCLE ? 'C' : 'c'); break; case TRB_SET_LT: - sprintf(str, + snprintf(str, size, "%s: belt %d flags %c", xhci_trb_type_string(type), TRB_TO_BELT(field3), field3 & TRB_CYCLE ? 'C' : 'c'); break; case TRB_GET_BW: - sprintf(str, + snprintf(str, size, "%s: ctx %08x%08x slot %d speed %d flags %c", xhci_trb_type_string(type), field1, field0, @@ -2437,7 +2442,7 @@ static inline const char *xhci_decode_trb(u32 field0, u32 field1, u32 field2, field3 & TRB_CYCLE ? 'C' : 'c'); break; case TRB_FORCE_HEADER: - sprintf(str, + snprintf(str, size, "%s: info %08x%08x%08x pkt type %d roothub port %d flags %c", xhci_trb_type_string(type), field2, field1, field0 & 0xffffffe0, @@ -2446,7 +2451,7 @@ static inline const char *xhci_decode_trb(u32 field0, u32 field1, u32 field2, field3 & TRB_CYCLE ? 'C' : 'c'); break; default: - sprintf(str, + snprintf(str, size, "type '%s' -> raw %08x %08x %08x %08x", xhci_trb_type_string(type), field0, field1, field2, field3); @@ -2571,9 +2576,8 @@ static inline const char *xhci_portsc_link_state_string(u32 portsc) return "Unknown"; }

-static inline const char *xhci_decode_portsc(u32 portsc) +static inline const char *xhci_decode_portsc(char *str, u32 portsc) { - static char str[256]; int ret;

ret = sprintf(str, "%s %s %s Link:%s PortSpeed:%d ",