The simple_str* family of functions perform no error checking in scenarios where the input value overflows the intended output variable. This results in these functions successfully returning even when the output does not match the input string. Or as it was mentioned [1], "...simple_strtol(), simple_strtoll(), simple_strtoul(), and simple_strtoull() functions explicitly ignore overflows, which may lead to unexpected results in callers." Hence, the use of those functions is discouraged. This patch replaces all uses of the simple_strto* series of functions with their safer kstrto* alternatives. Side effects of this patch: - Every string to long or long long conversion using kstrto* is now checked for failure. - kstrto* errors are handled with appropriate `KDB_BADINT` wherever applicable. - A good side effect is that we end up saving a few lines of code since unlike in simple_strto* functions, kstrto functions do not need an additional "end pointer" variable, and the return values of the latter can be directly checked in an "if" statement without the need to define additional `ret` or `err` variables. This, of course, results in cleaner, yet still easy to understand code. [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#simple-strtol-simple-strtoll-simple-strtoul-simple-strtoull
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| @@ -306,8 +306,8 @@ static int kdbgetulenv(const char *match, unsigned long *value) · 305 unmodified lines | |||
| 306 | return KDB_NOTENV; | 306 | return KDB_NOTENV; |
| 307 | if (strlen(ep) == 0) | 307 | if (strlen(ep) == 0) |
| 308 | return KDB_NOENVVALUE; | 308 | return KDB_NOENVVALUE; |
| 309 | 309 | if (kstrtoul(ep, 0, value)) | |
| 310 | *value = simple_strtoul(ep, NULL, 0); | 310 | return KDB_BADINT; |
| 311 | 311 | ||
| 312 | return 0; | 312 | return 0; |
| 313 | } | 313 | } |
| @@ -402,42 +402,23 @@ static void kdb_printenv(void) · 88 unmodified lines | |||
| 402 | */ | 402 | */ |
| 403 | int kdbgetularg(const char *arg, unsigned long *value) | 403 | int kdbgetularg(const char *arg, unsigned long *value) |
| 404 | { | 404 | { |
| 405 | char *endp; | 405 | /* |
| 406 | unsigned long val; | 406 | * If the first fails, also try base 16, for us |
| 407 | 407 | * folks too lazy to type the leading 0x... | |
| 408 | val = simple_strtoul(arg, &endp, 0); | 408 | */ |
| 409 | 409 | if (kstrtoul(arg, 0, value)) { | |
| 410 | if (endp == arg) { | 410 | if (kstrtoul(arg, 16, value)) |
| 411 | /* | ||
| 412 | * Also try base 16, for us folks too lazy to type the | ||
| 413 | * leading 0x... | ||
| 414 | */ | ||
| 415 | val = simple_strtoul(arg, &endp, 16); | ||
| 416 | if (endp == arg) | ||
| 417 | return KDB_BADINT; | 411 | return KDB_BADINT; |
| 418 | } | 412 | } |
| 419 | |||
| 420 | *value = val; | ||
| 421 | |||
| 422 | return 0; | 413 | return 0; |
| 423 | } | 414 | } |
| 424 | 415 | ||
| 425 | int kdbgetu64arg(const char *arg, u64 *value) | 416 | int kdbgetu64arg(const char *arg, u64 *value) |
| 426 | { | 417 | { |
| 427 | char *endp; | 418 | if (kstrtou64(arg, 0, value)) { |
| 428 | u64 val; | 419 | if (kstrtou64(arg, 16, value)) |
| 429 | |||
| 430 | val = simple_strtoull(arg, &endp, 0); | ||
| 431 | |||
| 432 | if (endp == arg) { | ||
| 433 | |||
| 434 | val = simple_strtoull(arg, &endp, 16); | ||
| 435 | if (endp == arg) | ||
| 436 | return KDB_BADINT; | 420 | return KDB_BADINT; |
| 437 | } | 421 | } |
| 438 | |||
| 439 | *value = val; | ||
| 440 | |||
| 441 | return 0; | 422 | return 0; |
| 442 | } | 423 | } |
| 443 | 424 | ||
| @@ -473,10 +454,10 @@ int kdb_set(int argc, const char **argv) · 29 unmodified lines | |||
| 473 | */ | 454 | */ |
| 474 | if (strcmp(argv[1], "KDBDEBUG") == 0) { | 455 | if (strcmp(argv[1], "KDBDEBUG") == 0) { |
| 475 | unsigned int debugflags; | 456 | unsigned int debugflags; |
| 476 | char *cp; | 457 | int ret; |
| 477 | 458 | ||
| 478 | debugflags = simple_strtoul(argv[2], &cp, 0); | 459 | ret = kstrtouint(argv[2], 0, &debugflags); |
| 479 | if (cp == argv[2] || debugflags & ~KDB_DEBUG_FLAG_MASK) { | 460 | if (ret || debugflags & ~KDB_DEBUG_FLAG_MASK) { |
| 480 | kdb_printf("kdb: illegal debug flags '%s'\n", | 461 | kdb_printf("kdb: illegal debug flags '%s'\n", |
| 481 | argv[2]); | 462 | argv[2]); |
| 482 | return 0; | 463 | return 0; |
| @@ -1619,10 +1600,10 @@ static int kdb_md(int argc, const char **argv) · 1136 unmodified lines | |||
| 1619 | if (!argv[0][3]) | 1600 | if (!argv[0][3]) |
| 1620 | valid = 1; | 1601 | valid = 1; |
| 1621 | else if (argv[0][3] == 'c' && argv[0][4]) { | 1602 | else if (argv[0][3] == 'c' && argv[0][4]) { |
| 1622 | char *p; | 1603 | if (kstrtouint(argv[0] + 4, 10, &repeat)) |
| 1623 | repeat = simple_strtoul(argv[0] + 4, &p, 10); | 1604 | return KDB_BADINT; |
| 1624 | mdcount = ((repeat * bytesperword) + 15) / 16; | 1605 | mdcount = ((repeat * bytesperword) + 15) / 16; |
| 1625 | valid = !*p; | 1606 | valid = 1; |
| 1626 | } | 1607 | } |
| 1627 | last_repeat = repeat; | 1608 | last_repeat = repeat; |
| 1628 | } else if (strcmp(argv[0], "md") == 0) | 1609 | } else if (strcmp(argv[0], "md") == 0) |
| @@ -2083,15 +2064,10 @@ static int kdb_dmesg(int argc, const char **argv) · 454 unmodified lines | |||
| 2083 | if (argc > 2) | 2064 | if (argc > 2) |
| 2084 | return KDB_ARGCOUNT; | 2065 | return KDB_ARGCOUNT; |
| 2085 | if (argc) { | 2066 | if (argc) { |
| 2086 | char *cp; | 2067 | if (kstrtoint(argv[1], 0, &lines)) |
| 2087 | lines = simple_strtol(argv[1], &cp, 0); | ||
| 2088 | if (*cp) | ||
| 2089 | lines = 0; | 2068 | lines = 0; |
| 2090 | if (argc > 1) { | 2069 | if (argc > 1 && (kstrtoint(argv[2], 0, &adjust) || adjust < 0)) |
| 2091 | adjust = simple_strtoul(argv[2], &cp, 0); | 2070 | adjust = 0; |
| 2092 | if (*cp || adjust < 0) | ||
| 2093 | adjust = 0; | ||
| 2094 | } | ||
| 2095 | } | 2071 | } |
| 2096 | 2072 | ||
| 2097 | /* disable LOGGING if set */ | 2073 | /* disable LOGGING if set */ |
| @@ -2428,14 +2404,12 @@ static int kdb_help(int argc, const char **argv) · 330 unmodified lines | |||
| 2428 | static int kdb_kill(int argc, const char **argv) | 2404 | static int kdb_kill(int argc, const char **argv) |
| 2429 | { | 2405 | { |
| 2430 | long sig, pid; | 2406 | long sig, pid; |
| 2431 | char *endp; | ||
| 2432 | struct task_struct *p; | 2407 | struct task_struct *p; |
| 2433 | 2408 | ||
| 2434 | if (argc != 2) | 2409 | if (argc != 2) |
| 2435 | return KDB_ARGCOUNT; | 2410 | return KDB_ARGCOUNT; |
| 2436 | 2411 | ||
| 2437 | sig = simple_strtol(argv[1], &endp, 0); | 2412 | if (kstrtol(argv[1], 0, &sig)) |
| 2438 | if (*endp) | ||
| 2439 | return KDB_BADINT; | 2413 | return KDB_BADINT; |
| 2440 | if ((sig >= 0) || !valid_signal(-sig)) { | 2414 | if ((sig >= 0) || !valid_signal(-sig)) { |
| 2441 | kdb_printf("Invalid signal parameter.<-signal>\n"); | 2415 | kdb_printf("Invalid signal parameter.<-signal>\n"); |
| @@ -2443,8 +2417,7 @@ static int kdb_kill(int argc, const char **argv) · 1 unmodified line | |||
| 2443 | } | 2417 | } |
| 2444 | sig = -sig; | 2418 | sig = -sig; |
| 2445 | 2419 | ||
| 2446 | pid = simple_strtol(argv[2], &endp, 0); | 2420 | if (kstrtol(argv[2], 0, &pid)) |
| 2447 | if (*endp) | ||
| 2448 | return KDB_BADINT; | 2421 | return KDB_BADINT; |
| 2449 | if (pid <= 0) { | 2422 | if (pid <= 0) { |
| 2450 | kdb_printf("Process ID must be large than 0.\n"); | 2423 | kdb_printf("Process ID must be large than 0.\n"); |