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 the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: xhci-fix-unsafe-memory-usage-in-xhci-tracing.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From cbf286e8ef8337308c259ff5b9ce2e74d403be5a Mon Sep 17 00:00:00 2001 From: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> Date: Fri, 20 Aug 2021 15:34:58 +0300 Subject: xhci: fix unsafe memory usage in xhci tracing From: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> commit cbf286e8ef8337308c259ff5b9ce2e74d403be5a upstream. 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@xxxxxxxxxxxxxxx> Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20210820123503.2605901-2-mathias.nyman@xxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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(-) --- a/drivers/usb/host/xhci-debugfs.c +++ b/drivers/usb/host/xhci-debugfs.c @@ -198,12 +198,13 @@ static void xhci_ring_dump_segment(struc 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]))); @@ -345,9 +346,10 @@ static int xhci_portsc_show(struct seq_f { 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; } --- 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) ) ); @@ -526,6 +525,7 @@ 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; @@ -533,7 +533,7 @@ 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) ) ); --- 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) @@ -2223,15 +2226,14 @@ static inline char *xhci_slot_state_stri } } -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), @@ -2248,7 +2250,7 @@ static inline const char *xhci_decode_tr 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)), @@ -2261,7 +2263,8 @@ static inline const char *xhci_decode_tr 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, @@ -2278,7 +2281,8 @@ static inline const char *xhci_decode_tr 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), @@ -2291,7 +2295,8 @@ static inline const char *xhci_decode_tr 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), @@ -2304,7 +2309,7 @@ static inline const char *xhci_decode_tr 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), @@ -2321,21 +2326,21 @@ static inline const char *xhci_decode_tr 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, @@ -2344,7 +2349,7 @@ static inline const char *xhci_decode_tr 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, @@ -2353,7 +2358,7 @@ static inline const char *xhci_decode_tr 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, @@ -2361,7 +2366,7 @@ static inline const char *xhci_decode_tr 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, @@ -2382,7 +2387,7 @@ static inline const char *xhci_decode_tr 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, @@ -2393,14 +2398,14 @@ static inline const char *xhci_decode_tr 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, @@ -2409,14 +2414,14 @@ static inline const char *xhci_decode_tr 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, @@ -2425,7 +2430,7 @@ static inline const char *xhci_decode_tr 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, @@ -2434,7 +2439,7 @@ static inline const char *xhci_decode_tr 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); @@ -2557,9 +2562,8 @@ static inline const char *xhci_portsc_li 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 ", Patches currently in stable-queue which might be from mathias.nyman@xxxxxxxxxxxxxxx are queue-5.10/xhci-fix-unsafe-memory-usage-in-xhci-tracing.patch queue-5.10/xhci-fix-even-more-unsafe-memory-usage-in-xhci-tracing.patch