From afe2dab4f6d32d5650aaba42f2c7ec9c0622f4dd Mon Sep 17 00:00:00 2001 From: Nathaniel McCallum Date: Wed, 18 Nov 2009 20:11:23 -0500 Subject: USB: add hex/bcd detection to usb modalias generation The current code to generate usb modaliases from usb_device_id assumes that the device's bcdDevice descriptor will actually be in BCD format. While this should be a sane assumption, some devices don't follow spec and just use plain old hex. This causes drivers for these devices to generate invalid modalias lines which will never actually match for the hardware. The following patch adds hex support for bcdDevice in file2alias.c by detecting when a driver uses a hex formatted bcdDevice_(lo|hi) and adjusts the output to hex format accordingly. Drivers for devices which have bcdDevice conforming to BCD will have no change in modalias output. Drivers for devices which don't conform (i.e. ibmcam) should now generate valid modaliases. EXAMPLE OUTPUT (ibmcam; space added to highlight change) Old: usb:v0545p800D d030[10-9] dc*dsc*dp*ic*isc*ip* New: usb:v0545p800D d030a dc*dsc*dp*ic*isc*ip* Signed-off-by: Nathaniel McCallum Signed-off-by: Greg Kroah-Hartman --- scripts/mod/file2alias.c | 48 ++++++++++++++++++++++++++++++++++++------------ 1 file changed, 36 insertions(+), 12 deletions(-) (limited to 'scripts/mod/file2alias.c') diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c index 62a9025cdcc..e31f03aaf29 100644 --- a/scripts/mod/file2alias.c +++ b/scripts/mod/file2alias.c @@ -104,7 +104,7 @@ static void device_id_check(const char *modname, const char *device_id, static void do_usb_entry(struct usb_device_id *id, unsigned int bcdDevice_initial, int bcdDevice_initial_digits, unsigned char range_lo, unsigned char range_hi, - struct module *mod) + unsigned char max, struct module *mod) { char alias[500]; strcpy(alias, "usb:"); @@ -118,9 +118,22 @@ static void do_usb_entry(struct usb_device_id *id, sprintf(alias + strlen(alias), "%0*X", bcdDevice_initial_digits, bcdDevice_initial); if (range_lo == range_hi) - sprintf(alias + strlen(alias), "%u", range_lo); - else if (range_lo > 0 || range_hi < 9) - sprintf(alias + strlen(alias), "[%u-%u]", range_lo, range_hi); + sprintf(alias + strlen(alias), "%X", range_lo); + else if (range_lo > 0 || range_hi < max) { + if (range_lo > 0x9 || range_hi < 0xA) + sprintf(alias + strlen(alias), + "[%X-%X]", + range_lo, + range_hi); + else { + sprintf(alias + strlen(alias), + range_lo < 0x9 ? "[%X-9" : "[%X", + range_lo); + sprintf(alias + strlen(alias), + range_hi > 0xA ? "a-%X]" : "%X]", + range_lo); + } + } if (bcdDevice_initial_digits < (sizeof(id->bcdDevice_lo) * 2 - 1)) strcat(alias, "*"); @@ -150,7 +163,7 @@ static void do_usb_entry(struct usb_device_id *id, static void do_usb_entry_multi(struct usb_device_id *id, struct module *mod) { unsigned int devlo, devhi; - unsigned char chi, clo; + unsigned char chi, clo, max; int ndigits; id->match_flags = TO_NATIVE(id->match_flags); @@ -162,6 +175,17 @@ static void do_usb_entry_multi(struct usb_device_id *id, struct module *mod) devhi = id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI ? TO_NATIVE(id->bcdDevice_hi) : ~0x0U; + /* Figure out if this entry is in bcd or hex format */ + max = 0x9; /* Default to decimal format */ + for (ndigits = 0 ; ndigits < sizeof(id->bcdDevice_lo) * 2 ; ndigits++) { + clo = (devlo >> (ndigits << 2)) & 0xf; + chi = ((devhi > 0x9999 ? 0x9999 : devhi) >> (ndigits << 2)) & 0xf; + if (clo > max || chi > max) { + max = 0xf; + break; + } + } + /* * Some modules (visor) have empty slots as placeholder for * run-time specification that results in catch-all alias @@ -173,21 +197,21 @@ static void do_usb_entry_multi(struct usb_device_id *id, struct module *mod) for (ndigits = sizeof(id->bcdDevice_lo) * 2 - 1; devlo <= devhi; ndigits--) { clo = devlo & 0xf; chi = devhi & 0xf; - if (chi > 9) /* it's bcd not hex */ - chi = 9; + if (chi > max) /* If we are in bcd mode, truncate if necessary */ + chi = max; devlo >>= 4; devhi >>= 4; if (devlo == devhi || !ndigits) { - do_usb_entry(id, devlo, ndigits, clo, chi, mod); + do_usb_entry(id, devlo, ndigits, clo, chi, max, mod); break; } - if (clo > 0) - do_usb_entry(id, devlo++, ndigits, clo, 9, mod); + if (clo > 0x0) + do_usb_entry(id, devlo++, ndigits, clo, max, max, mod); - if (chi < 9) - do_usb_entry(id, devhi--, ndigits, 0, chi, mod); + if (chi < max) + do_usb_entry(id, devhi--, ndigits, 0x0, chi, max, mod); } } -- cgit v1.2.3-70-g09d2 From 55f49f26821f379c451deb9fd6de8e59afb9b37e Mon Sep 17 00:00:00 2001 From: Nathaniel McCallum Date: Wed, 18 Nov 2009 20:15:28 -0500 Subject: USB: handle bcd incrementation in usb modalias generation This patch fixes a bug when incrementing/decrementing on a BCD formatted integer (i.e. 0x09++ should be 0x10 not 0x0A). It just adds a function for incrementing/decrementing BCD integers by converting to decimal, doing the increment/decrement and then converting back to BCD. Signed-off-by: Nathaniel McCallum Signed-off-by: Greg Kroah-Hartman --- scripts/mod/file2alias.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 47 insertions(+), 2 deletions(-) (limited to 'scripts/mod/file2alias.c') diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c index e31f03aaf29..6f426afbc52 100644 --- a/scripts/mod/file2alias.c +++ b/scripts/mod/file2alias.c @@ -160,6 +160,45 @@ static void do_usb_entry(struct usb_device_id *id, "MODULE_ALIAS(\"%s\");\n", alias); } +/* Handles increment/decrement of BCD formatted integers */ +/* Returns the previous value, so it works like i++ or i-- */ +static unsigned int incbcd(unsigned int *bcd, + int inc, + unsigned char max, + size_t chars) +{ + unsigned int init = *bcd, i, j; + unsigned long long c, dec = 0; + + /* If bcd is not in BCD format, just increment */ + if (max > 0x9) { + *bcd += inc; + return init; + } + + /* Convert BCD to Decimal */ + for (i=0 ; i < chars ; i++) { + c = (*bcd >> (i << 2)) & 0xf; + c = c > 9 ? 9 : c; /* force to bcd just in case */ + for (j=0 ; j < i ; j++) + c = c * 10; + dec += c; + } + + /* Do our increment/decrement */ + dec += inc; + *bcd = 0; + + /* Convert back to BCD */ + for (i=0 ; i < chars ; i++) { + for (c=1,j=0 ; j < i ; j++) + c = c * 10; + c = (dec / c) % 10; + *bcd += c << (i << 2); + } + return init; +} + static void do_usb_entry_multi(struct usb_device_id *id, struct module *mod) { unsigned int devlo, devhi; @@ -208,10 +247,16 @@ static void do_usb_entry_multi(struct usb_device_id *id, struct module *mod) } if (clo > 0x0) - do_usb_entry(id, devlo++, ndigits, clo, max, max, mod); + do_usb_entry(id, + incbcd(&devlo, 1, max, + sizeof(id->bcdDevice_lo) * 2), + ndigits, clo, max, max, mod); if (chi < max) - do_usb_entry(id, devhi--, ndigits, 0x0, chi, max, mod); + do_usb_entry(id, + incbcd(&devhi, -1, max, + sizeof(id->bcdDevice_lo) * 2), + ndigits, 0x0, chi, max, mod); } } -- cgit v1.2.3-70-g09d2 From 3a5dd791abef032fe57fc652c0232913c696e59b Mon Sep 17 00:00:00 2001 From: Mike Frysinger Date: Sun, 17 Jan 2010 08:27:34 +1030 Subject: modpost: fix segfault in sym_is() with prefixed arches The sym_is() compares a symbol in an attempt to automatically skip symbol prefixes. It does this first by searching the real symbol with the normal unprefixed symbol. But then it uses the length of the original symbol to check the end of the substring instead of the length of the symbol it is looking for. On non-prefixed arches, this is effectively the same thing, so there is no problem. On prefixed-arches, since this is exceeds by just one byte, a crash is rare and it is usually a NUL byte anyways. But every once in a blue moon, you get the right page alignment and it segfaults. For example, on the Blackfin arch, sym_is() will be called with the real symbol "___mod_usb_device_table" as "symbol" when looking for the normal symbol "__mod_usb_device_table" as "name". The substring will thus return one byte into "symbol" and store it into "match". But then "match" will be indexed with the length of "symbol" instead of "name" and so we will exceed the storage. i.e. the code ends up doing: char foo[] = "abc"; return foo[strlen(foo)+1] == '\0'; Signed-off-by: Mike Frysinger Signed-off-by: Rusty Russell Signed-off-by: Linus Torvalds --- scripts/mod/file2alias.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/mod/file2alias.c') diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c index 6f426afbc52..220213e603d 100644 --- a/scripts/mod/file2alias.c +++ b/scripts/mod/file2alias.c @@ -804,7 +804,7 @@ static inline int sym_is(const char *symbol, const char *name) match = strstr(symbol, name); if (!match) return 0; - return match[strlen(symbol)] == '\0'; + return match[strlen(name)] == '\0'; } static void do_table(void *symval, unsigned long size, -- cgit v1.2.3-70-g09d2