} } # check for data_race without a comment. if ($line =~ /\bdata_race\s*\(/) { if (!ctx_has_comment($first_line, $linenr)) { WARN("DATA_RACE", "data_race without comment\n" . $herecurr); } } # check of hardware specific defines if ($line =~ m@^.\s*\#\s*if.*\b(__i386__|__powerpc64__|__sun__|__s390x__)\b@ && $realfile !~ m@include/asm-@) { CHK("ARCH_DEFINES", "architecture specific defines should be avoided\n" . $herecurr); } # check that the storage class is not after a type if ($line =~ /\b($Type)\s+($Storage)\b/) { WARN("STORAGE_CLASS", "storage class '$2' should be located before type '$1'\n" . $herecurr); }# Check that the storage class is at the beginning of a declaration if ($line =~ /\b$Storage\b/ && $line !~ /^.\s*$Storage/ && $line =~ /^.\s*(.+?)\$Storage\s/ && $1 !~ /[\,\)]\s*$/) { WARN("STORAGE_CLASS", "storage class should be at the beginning of the declaration\n" . $herecurr); } # check the location of the inline attribute, that it is between# storage class and type. if ($line =~ /\b$Type\s+$Inline\b/ || $line =~ /\b$Inline\s+$Storage\b/) { ERROR("INLINE_LOCATION", "inline keyword should sit between storage class and type\n" . $herecurr); } # Check for __inline__ and __inline, prefer inline if ($realfile !~ m@\binclude/uapi/@ && $line =~ /\b(__inline__|__inline)\b/) { if (WARN("INLINE", "plain inline is preferred over $1\n" . $herecurr) && $fix) { $fixed[$fixlinenr] =~ s/\b(__inline__|__inline)\b/inline/; } } # Check for __attribute__ packed, prefer __packed if ($realfile !~ m@\binclude/uapi/@ && $line =~ /\b__attribute__\s*\(\s*\(.*\bpacked\b/) { WARN("PREFER_PACKED", "__packed is preferred over __attribute__((packed))\n" . $herecurr); } # Check for __attribute__ aligned, prefer __aligned if ($realfile !~ m@\binclude/uapi/@ && $line =~ /\b__attribute__\s*\(\s*\(.*aligned/) { WARN("PREFER_ALIGNED", "__aligned(size) is preferred over __attribute__((aligned(size)))\n" . $herecurr); } # Check for __attribute__ section, prefer __section if ($realfile !~ m@\binclude/uapi/@ && $line =~ /\b__attribute__\s*\(\s*\(.*_*section_*\s*\(\s*("[^"]*")/) { my $old = substr($rawline, $-[1], $+[1] - $-[1]); my $new = substr($old, 1, -1); if (WARN("PREFER_SECTION", "__section($new) is preferred over __attribute__((section($old)))\n" . $herecurr) && $fix) { $fixed[$fixlinenr] =~ s/\b__attribute__\s*\(\s*\(\s*_*section_*\s*\(\s*\Q$old\E\s*\)\s*\)\s*\)/__section($new)/; } } # Check for __attribute__ format(printf, prefer __printf if ($realfile !~ m@\binclude/uapi/@ && $line =~ /\b__attribute__\s*\(\s*\(\s*format\s*\(\s*printf/) { if (WARN("PREFER_PRINTF", "__printf(string-index, first-to-check) is preferred over __attribute__((format(printf, string-index, first-to-check)))\n" . $herecurr) && $fix) { $fixed[$fixlinenr] =~ s/\b__attribute__\s*\(\s*\(\s*format\s*\(\s*printf\s*,\s*(.*)\)\s*\)\s*\)/"__printf(" . trim($1) . ")"/ex; } } # Check for __attribute__ format(scanf, prefer __scanf if ($realfile !~ m@\binclude/uapi/@ && $line =~ /\b__attribute__\s*\(\s*\(\s*format\s*\(\s*scanf\b/) { if (WARN("PREFER_SCANF", "__scanf(string-index, first-to-check) is preferred over __attribute__((format(scanf, string-index, first-to-check)))\n" . $herecurr) && $fix) { $fixed[$fixlinenr] =~ s/\b__attribute__\s*\(\s*\(\s*format\s*\(\s*scanf\s*,\s*(.*)\)\s*\)\s*\)/"__scanf(" . trim($1) . ")"/ex; } } # Check for __attribute__ weak, or __weak declarations (may have link issues) if ($perl_version_ok && $line =~ /(?:$Declare|$DeclareMisordered)\s*$Ident\s*$balanced_parens\s*(?:$Attribute)?\s*;/ && ($line =~ /\b__attribute__\s*\(\s*\(.*\bweak\b/ || $line =~ /\b__weak\b/)) { ERROR("WEAK_DECLARATION", "Using weak declarations can have unintended link defects\n" . $herecurr); } # check for c99 types like uint8_t used outside of uapi/ and tools/ if ($realfile !~ m@\binclude/uapi/@ && $realfile !~ m@\btools/@ && $line =~ /\b($Declare)\s*$Ident\s*[=;,\[]/) { my $type = $1; if ($type =~ /\b($typeC99Typedefs)\b/) { $type = $1; my $kernel_type = 'u'; $kernel_type = 's' if ($type =~ /^_*[si]/); $type =~ /(\d+)/; $kernel_type .= $1; if (CHK("PREFER_KERNEL_TYPES", "Prefer kernel type '$kernel_type' over '$type'\n" . $herecurr) && $fix) { $fixed[$fixlinenr] =~ s/\b$type\b/$kernel_type/; } } } # check for cast of C90 native int or longer types constants if ($line =~ /(\(\s*$C90_int_types\s*\)\s*)($Constant)\b/) { my $cast = $1; my $const = $2; if (WARN("TYPECAST_INT_CONSTANT", "Unnecessary typecast of c90 int constant\n" . $herecurr) && $fix) { my $suffix = ""; my $newconst = $const; $newconst =~ s/${Int_type}$//; $suffix .= 'U' if ($cast =~ /\bunsigned\b/); if ($cast =~ /\blong\s+long\b/) { $suffix .= 'LL'; } elsif ($cast =~ /\blong\b/) { $suffix .= 'L'; } $fixed[$fixlinenr] =~ s/\Q$cast\E$const\b/$newconst$suffix/; } } # check for sizeof(&) if ($line =~ /\bsizeof\s*\(\s*\&/) { WARN("SIZEOF_ADDRESS", "sizeof(& should be avoided\n" . $herecurr); } # check for sizeof without parenthesis if ($line =~ /\bsizeof\s+((?:\*\s*|)$Lval|$Type(?:\s+$Lval|))/) { if (WARN("SIZEOF_PARENTHESIS", "sizeof $1 should be sizeof($1)\n" . $herecurr) && $fix) { $fixed[$fixlinenr] =~ s/\bsizeof\s+((?:\*\s*|)$Lval|$Type(?:\s+$Lval|))/"sizeof(" . trim($1) . ")"/ex; } } # check for struct spinlock declarations if ($line =~ /^.\s*\bstruct\s+spinlock\s+\w+\s*;/) { WARN("USE_SPINLOCK_T", "struct spinlock should be spinlock_t\n" . $herecurr); } # check for seq_printf uses that could be seq_puts if ($sline =~ /\bseq_printf\s*\(.*"\s*\)\s*;\s*$/) { my $fmt = get_quoted_string($line, $rawline); $fmt =~ s/%%//g; if ($fmt !~ /%/) { if (WARN("PREFER_SEQ_PUTS", "Prefer seq_puts to seq_printf\n" . $herecurr) && $fix) { $fixed[$fixlinenr] =~ s/\bseq_printf\b/seq_puts/; } } } # check for vsprintf extension %p<foo> misuses if ($perl_version_ok && defined $stat && $stat =~ /^\+(?![^\{]*\{\s*).*\b(\w+)\s*\(.*$String\s*,/s && $1 !~ /^_*volatile_*$/) { my $stat_real; my $lc = $stat =~ tr@\n@@; $lc = $lc + $linenr; for (my $count = $linenr; $count <= $lc; $count++) { my $specifier; my $extension; my $qualifier; my $bad_specifier = ""; my $fmt = get_quoted_string($lines[$count - 1], raw_line($count, 0)); $fmt =~ s/%%//g; while ($fmt =~ /(\%[\*\d\.]*p(\w)(\w*))/g) { $specifier = $1; $extension = $2; $qualifier = $3; if ($extension !~ /[SsBKRraEehMmIiUDdgVCbGNOxtf]/ || ($extension eq "f" && defined $qualifier && $qualifier !~ /^w/)) { $bad_specifier = $specifier; last; } if ($extension eq "x" && !defined($stat_real)) { if (!defined($stat_real)) { $stat_real = get_stat_real($linenr, $lc); } WARN("VSPRINTF_SPECIFIER_PX", "Using vsprintf specifier '\%px' potentially exposes the kernel memory layout, if you don't really need the address please consider using '\%p'.\n" . "$here\n$stat_real\n"); } } if ($bad_specifier ne "") { my $stat_real = get_stat_real($linenr, $lc); my $ext_type = "Invalid"; my $use = ""; if ($bad_specifier =~ /p[Ff]/) { $use = " - use %pS instead"; $use =~ s/pS/ps/ if ($bad_specifier =~ /pf/); } WARN("VSPRINTF_POINTER_EXTENSION", "$ext_type vsprintf pointer extension '$bad_specifier'$use\n" . "$here\n$stat_real\n"); } } } # Check for misused memsets if ($perl_version_ok && defined $stat && $stat =~ /^\+(?:.*?)\bmemset\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*$FuncArg\s*\)/) { my $ms_addr = $2; my $ms_val = $7; my $ms_size = $12; if ($ms_size =~ /^(0x|)0$/i) { ERROR("MEMSET", "memset to 0's uses 0 as the 2nd argument, not the 3rd\n" . "$here\n$stat\n"); } elsif ($ms_size =~ /^(0x|)1$/i) { WARN("MEMSET", "single byte memset is suspicious. Swapped 2nd/3rd argument?\n" . "$here\n$stat\n"); } } # Check for memcpy(foo, bar, ETH_ALEN) that could be ether_addr_copy(foo, bar)# if ($perl_version_ok &&# defined $stat &&# $stat =~ /^\+(?:.*?)\bmemcpy\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*ETH_ALEN\s*\)/) {# if (WARN("PREFER_ETHER_ADDR_COPY",# "Prefer ether_addr_copy() over memcpy() if the Ethernet addresses are __aligned(2)\n" . "$here\n$stat\n") &&# $fix) {# $fixed[$fixlinenr] =~ s/\bmemcpy\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*ETH_ALEN\s*\)/ether_addr_copy($2, $7)/;# }# } # Check for memcmp(foo, bar, ETH_ALEN) that could be ether_addr_equal*(foo, bar)# if ($perl_version_ok &&# defined $stat &&# $stat =~ /^\+(?:.*?)\bmemcmp\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*ETH_ALEN\s*\)/) {# WARN("PREFER_ETHER_ADDR_EQUAL",# "Prefer ether_addr_equal() or ether_addr_equal_unaligned() over memcmp()\n" . "$here\n$stat\n")# } # check for memset(foo, 0x0, ETH_ALEN) that could be eth_zero_addr# check for memset(foo, 0xFF, ETH_ALEN) that could be eth_broadcast_addr# if ($perl_version_ok &&# defined $stat &&# $stat =~ /^\+(?:.*?)\bmemset\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*ETH_ALEN\s*\)/) {## my $ms_val = $7;## if ($ms_val =~ /^(?:0x|)0+$/i) {# if (WARN("PREFER_ETH_ZERO_ADDR",# "Prefer eth_zero_addr over memset()\n" . "$here\n$stat\n") &&# $fix) {# $fixed[$fixlinenr] =~ s/\bmemset\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*,\s*ETH_ALEN\s*\)/eth_zero_addr($2)/;# }# } elsif ($ms_val =~ /^(?:0xff|255)$/i) {# if (WARN("PREFER_ETH_BROADCAST_ADDR",# "Prefer eth_broadcast_addr() over memset()\n" . "$here\n$stat\n") &&# $fix) {# $fixed[$fixlinenr] =~ s/\bmemset\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*,\s*ETH_ALEN\s*\)/eth_broadcast_addr($2)/;# }# }# } # typecasts on min/max could be min_t/max_t if ($perl_version_ok && defined $stat && $stat =~ /^\+(?:.*?)\b(min|max)\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\)/) { if (defined $2 || defined $7) { my $call = $1; my $cast1 = deparenthesize($2); my $arg1 = $3; my $cast2 = deparenthesize($7); my $arg2 = $8; my $cast; if ($cast1 ne "" && $cast2 ne "" && $cast1 ne $cast2) { $cast = "$cast1 or $cast2"; } elsif ($cast1 ne "") { $cast = $cast1; } else { $cast = $cast2; } WARN("MINMAX", "$call() should probably be ${call}_t($cast, $arg1, $arg2)\n" . "$here\n$stat\n"); } } # check usleep_range arguments if ($perl_version_ok && defined $stat && $stat =~ /^\+(?:.*?)\busleep_range\s*\(\s*($FuncArg)\s*,\s*($FuncArg)\s*\)/) { my $min = $1; my $max = $7; if ($min eq $max) { WARN("USLEEP_RANGE", "usleep_range should not use min == max args; see Documentation/timers/timers-howto.rst\n" . "$here\n$stat\n"); } elsif ($min =~ /^\d+$/ && $max =~ /^\d+$/ && $min > $max) { WARN("USLEEP_RANGE", "usleep_range args reversed, use min then max; see Documentation/timers/timers-howto.rst\n" . "$here\n$stat\n"); } } # check for naked sscanf if ($perl_version_ok && defined $stat && $line =~ /\bsscanf\b/ && ($stat !~ /$Ident\s*=\s*sscanf\s*$balanced_parens/ && $stat !~ /\bsscanf\s*$balanced_parens\s*(?:$Compare)/ && $stat !~ /(?:$Compare)\s*\bsscanf\s*$balanced_parens/)) { my $lc = $stat =~ tr@\n@@; $lc = $lc + $linenr; my $stat_real = get_stat_real($linenr, $lc); WARN("NAKED_SSCANF", "unchecked sscanf return value\n" . "$here\n$stat_real\n"); } # check for simple sscanf that should be kstrto<foo> if ($perl_version_ok && defined $stat && $line =~ /\bsscanf\b/) { my $lc = $stat =~ tr@\n@@; $lc = $lc + $linenr; my $stat_real = get_stat_real($linenr, $lc); if ($stat_real =~ /\bsscanf\b\s*\(\s*$FuncArg\s*,\s*("[^"]+")/) { my $format = $6; my $count = $format =~ tr@%@%@; if ($count == 1 && $format =~ /^"\%(?i:ll[udxi]|[udxi]ll|ll|[hl]h?[udxi]|[udxi][hl]h?|[hl]h?|[udxi])"$/) { WARN("SSCANF_TO_KSTRTO", "Prefer kstrto<type> to single variable sscanf\n" . "$here\n$stat_real\n"); } } } # check for new externs in .h files. if ($realfile =~ /\.h$/ && $line =~ /^\+\s*(extern\s+)$Type\s*$Ident\s*\(/s) { if (CHK("AVOID_EXTERNS", "extern prototypes should be avoided in .h files\n" . $herecurr) && $fix) { $fixed[$fixlinenr] =~ s/(.*)\bextern\b\s*(.*)/$1$2/; } } # check for new externs in .c files. if ($realfile =~ /\.c$/ && defined $stat && $stat =~ /^.\s*(?:extern\s+)?$Type\s+($Ident)(\s*)\(/s) { my $function_name = $1; my $paren_space = $2; my $s = $stat; if (defined $cond) { substr($s, 0, length($cond), ''); } if ($s =~ /^\s*;/) { WARN("AVOID_EXTERNS", "externs should be avoided in .c files\n" . $herecurr); } if ($paren_space =~ /\n/) { WARN("FUNCTION_ARGUMENTS", "arguments for function declarations should follow identifier\n" . $herecurr); } } elsif ($realfile =~ /\.c$/ && defined $stat && $stat =~ /^.\s*extern\s+/) { WARN("AVOID_EXTERNS", "externs should be avoided in .c files\n" . $herecurr); } # check for function declarations that have arguments without identifier names if (defined $stat && $stat =~ /^.\s*(?:extern\s+)?$Type\s*(?:$Ident|\(\s*\*\s*$Ident\s*\))\s*\(\s*([^{]+)\s*\)\s*;/s && $1 ne "void") { my $args = trim($1); while ($args =~ m/\s*($Type\s*(?:$Ident|\(\s*\*\s*$Ident?\s*\)\s*$balanced_parens)?)/g) { my $arg = trim($1); if ($arg =~ /^$Type$/ && $arg !~ /enum\s+$Ident$/) { WARN("FUNCTION_ARGUMENTS", "function definition argument '$arg' should also have an identifier name\n" . $herecurr); } } } # check for function definitions if ($perl_version_ok && defined $stat && $stat =~ /^.\s*(?:$Storage\s+)?$Type\s*($Ident)\s*$balanced_parens\s*{/s) { $context_function = $1; # check for multiline function definition with misplaced open brace my $ok = 0; my $cnt = statement_rawlines($stat); my $herectx = $here . "\n"; for (my $n = 0; $n < $cnt; $n++) { my $rl = raw_line($linenr, $n); $herectx .= $rl . "\n"; $ok = 1 if ($rl =~ /^[ \+]\{/); $ok = 1 if ($rl =~ /\{/ && $n == 0); last if $rl =~ /^[ \+].*\{/; } if (!$ok) { ERROR("OPEN_BRACE", "open brace '{' following function definitions go on the next line\n" . $herectx); } } # checks for new __setup's if ($rawline =~ /\b__setup\("([^"]*)"/) { my $name = $1; if (!grep(/$name/, @setup_docs)) { CHK("UNDOCUMENTED_SETUP", "__setup appears un-documented -- check Documentation/admin-guide/kernel-parameters.txt\n" . $herecurr); } } # check for pointless casting of alloc functions if ($line =~ /\*\s*\)\s*$allocFunctions\b/) { WARN("UNNECESSARY_CASTS", "unnecessary cast may hide bugs, see http://c-faq.com/malloc/mallocnocast.html\n" . $herecurr); } # alloc style# p = alloc(sizeof(struct foo), ...) should be p = alloc(sizeof(*p), ...) if ($perl_version_ok && $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*((?:kv|k|v)[mz]alloc(?:_node)?)\s*\(\s*(sizeof\s*\(\s*struct\s+$Lval\s*\))/) { CHK("ALLOC_SIZEOF_STRUCT", "Prefer $3(sizeof(*$1)...) over $3($4...)\n" . $herecurr); } # check for k[mz]alloc with multiplies that could be kmalloc_array/kcalloc if ($perl_version_ok && defined $stat && $stat =~ /^\+\s*($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)\s*,/) { my $oldfunc = $3; my $a1 = $4; my $a2 = $10; my $newfunc = "kmalloc_array"; $newfunc = "kcalloc" if ($oldfunc eq "kzalloc"); my $r1 = $a1; my $r2 = $a2; if ($a1 =~ /^sizeof\s*\S/) { $r1 = $a2; $r2 = $a1; } if ($r1 !~ /^sizeof\b/ && $r2 =~ /^sizeof\s*\S/ && !($r1 =~ /^$Constant$/ || $r1 =~ /^[A-Z_][A-Z0-9_]*$/)) { my $cnt = statement_rawlines($stat); my $herectx = get_stat_here($linenr, $cnt, $here); if (WARN("ALLOC_WITH_MULTIPLY", "Prefer $newfunc over $oldfunc with multiply\n" . $herectx) && $cnt == 1 && $fix) { $fixed[$fixlinenr] =~ s/\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)/$1 . ' = ' . "$newfunc(" . trim($r1) . ', ' . trim($r2)/e; } } } # check for krealloc arg reuse if ($perl_version_ok && $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*krealloc\s*\(\s*($Lval)\s*,/ && $1 eq $3) { WARN("KREALLOC_ARG_REUSE", "Reusing the krealloc arg is almost always a bug\n" . $herecurr); } # check for alloc argument mismatch if ($line =~ /\b(kcalloc|kmalloc_array)\s*\(\s*sizeof\b/) {Lines 6001–6500 of 6972. Previous lines Load more
} } # check for data_race without a comment. if ($line =~ /\bdata_race\s*\(/) { if (!ctx_has_comment($first_line, $linenr)) { WARN("DATA_RACE", "data_race without comment\n" . $herecurr); } } # check of hardware specific defines if ($line =~ m@^.\s*\#\s*if.*\b(__i386__|__powerpc64__|__sun__|__s390x__)\b@ && $realfile !~ m@include/asm-@) { CHK("ARCH_DEFINES", "architecture specific defines should be avoided\n" . $herecurr); } # check that the storage class is not after a type if ($line =~ /\b($Type)\s+($Storage)\b/) { WARN("STORAGE_CLASS", "storage class '$2' should be located before type '$1'\n" . $herecurr); } # Check that the storage class is at the beginning of a declaration if ($line =~ /\b$Storage\b/ && $line !~ /^.\s*$Storage/ && $line =~ /^.\s*(.+?)\$Storage\s/ && $1 !~ /[\,\)]\s*$/) { WARN("STORAGE_CLASS", "storage class should be at the beginning of the declaration\n" . $herecurr); } # check the location of the inline attribute, that it is between # storage class and type. if ($line =~ /\b$Type\s+$Inline\b/ || $line =~ /\b$Inline\s+$Storage\b/) { ERROR("INLINE_LOCATION", "inline keyword should sit between storage class and type\n" . $herecurr); } # Check for __inline__ and __inline, prefer inline if ($realfile !~ m@\binclude/uapi/@ && $line =~ /\b(__inline__|__inline)\b/) { if (WARN("INLINE", "plain inline is preferred over $1\n" . $herecurr) && $fix) { $fixed[$fixlinenr] =~ s/\b(__inline__|__inline)\b/inline/; } } # Check for __attribute__ packed, prefer __packed if ($realfile !~ m@\binclude/uapi/@ && $line =~ /\b__attribute__\s*\(\s*\(.*\bpacked\b/) { WARN("PREFER_PACKED", "__packed is preferred over __attribute__((packed))\n" . $herecurr); } # Check for __attribute__ aligned, prefer __aligned if ($realfile !~ m@\binclude/uapi/@ && $line =~ /\b__attribute__\s*\(\s*\(.*aligned/) { WARN("PREFER_ALIGNED", "__aligned(size) is preferred over __attribute__((aligned(size)))\n" . $herecurr); } # Check for __attribute__ section, prefer __section if ($realfile !~ m@\binclude/uapi/@ && $line =~ /\b__attribute__\s*\(\s*\(.*_*section_*\s*\(\s*("[^"]*")/) { my $old = substr($rawline, $-[1], $+[1] - $-[1]); my $new = substr($old, 1, -1); if (WARN("PREFER_SECTION", "__section($new) is preferred over __attribute__((section($old)))\n" . $herecurr) && $fix) { $fixed[$fixlinenr] =~ s/\b__attribute__\s*\(\s*\(\s*_*section_*\s*\(\s*\Q$old\E\s*\)\s*\)\s*\)/__section($new)/; } } # Check for __attribute__ format(printf, prefer __printf if ($realfile !~ m@\binclude/uapi/@ && $line =~ /\b__attribute__\s*\(\s*\(\s*format\s*\(\s*printf/) { if (WARN("PREFER_PRINTF", "__printf(string-index, first-to-check) is preferred over __attribute__((format(printf, string-index, first-to-check)))\n" . $herecurr) && $fix) { $fixed[$fixlinenr] =~ s/\b__attribute__\s*\(\s*\(\s*format\s*\(\s*printf\s*,\s*(.*)\)\s*\)\s*\)/"__printf(" . trim($1) . ")"/ex; } } # Check for __attribute__ format(scanf, prefer __scanf if ($realfile !~ m@\binclude/uapi/@ && $line =~ /\b__attribute__\s*\(\s*\(\s*format\s*\(\s*scanf\b/) { if (WARN("PREFER_SCANF", "__scanf(string-index, first-to-check) is preferred over __attribute__((format(scanf, string-index, first-to-check)))\n" . $herecurr) && $fix) { $fixed[$fixlinenr] =~ s/\b__attribute__\s*\(\s*\(\s*format\s*\(\s*scanf\s*,\s*(.*)\)\s*\)\s*\)/"__scanf(" . trim($1) . ")"/ex; } } # Check for __attribute__ weak, or __weak declarations (may have link issues) if ($perl_version_ok && $line =~ /(?:$Declare|$DeclareMisordered)\s*$Ident\s*$balanced_parens\s*(?:$Attribute)?\s*;/ && ($line =~ /\b__attribute__\s*\(\s*\(.*\bweak\b/ || $line =~ /\b__weak\b/)) { ERROR("WEAK_DECLARATION", "Using weak declarations can have unintended link defects\n" . $herecurr); } # check for c99 types like uint8_t used outside of uapi/ and tools/ if ($realfile !~ m@\binclude/uapi/@ && $realfile !~ m@\btools/@ && $line =~ /\b($Declare)\s*$Ident\s*[=;,\[]/) { my $type = $1; if ($type =~ /\b($typeC99Typedefs)\b/) { $type = $1; my $kernel_type = 'u'; $kernel_type = 's' if ($type =~ /^_*[si]/); $type =~ /(\d+)/; $kernel_type .= $1; if (CHK("PREFER_KERNEL_TYPES", "Prefer kernel type '$kernel_type' over '$type'\n" . $herecurr) && $fix) { $fixed[$fixlinenr] =~ s/\b$type\b/$kernel_type/; } } } # check for cast of C90 native int or longer types constants if ($line =~ /(\(\s*$C90_int_types\s*\)\s*)($Constant)\b/) { my $cast = $1; my $const = $2; if (WARN("TYPECAST_INT_CONSTANT", "Unnecessary typecast of c90 int constant\n" . $herecurr) && $fix) { my $suffix = ""; my $newconst = $const; $newconst =~ s/${Int_type}$//; $suffix .= 'U' if ($cast =~ /\bunsigned\b/); if ($cast =~ /\blong\s+long\b/) { $suffix .= 'LL'; } elsif ($cast =~ /\blong\b/) { $suffix .= 'L'; } $fixed[$fixlinenr] =~ s/\Q$cast\E$const\b/$newconst$suffix/; } } # check for sizeof(&) if ($line =~ /\bsizeof\s*\(\s*\&/) { WARN("SIZEOF_ADDRESS", "sizeof(& should be avoided\n" . $herecurr); } # check for sizeof without parenthesis if ($line =~ /\bsizeof\s+((?:\*\s*|)$Lval|$Type(?:\s+$Lval|))/) { if (WARN("SIZEOF_PARENTHESIS", "sizeof $1 should be sizeof($1)\n" . $herecurr) && $fix) { $fixed[$fixlinenr] =~ s/\bsizeof\s+((?:\*\s*|)$Lval|$Type(?:\s+$Lval|))/"sizeof(" . trim($1) . ")"/ex; } } # check for struct spinlock declarations if ($line =~ /^.\s*\bstruct\s+spinlock\s+\w+\s*;/) { WARN("USE_SPINLOCK_T", "struct spinlock should be spinlock_t\n" . $herecurr); } # check for seq_printf uses that could be seq_puts if ($sline =~ /\bseq_printf\s*\(.*"\s*\)\s*;\s*$/) { my $fmt = get_quoted_string($line, $rawline); $fmt =~ s/%%//g; if ($fmt !~ /%/) { if (WARN("PREFER_SEQ_PUTS", "Prefer seq_puts to seq_printf\n" . $herecurr) && $fix) { $fixed[$fixlinenr] =~ s/\bseq_printf\b/seq_puts/; } } } # check for vsprintf extension %p<foo> misuses if ($perl_version_ok && defined $stat && $stat =~ /^\+(?![^\{]*\{\s*).*\b(\w+)\s*\(.*$String\s*,/s && $1 !~ /^_*volatile_*$/) { my $stat_real; my $lc = $stat =~ tr@\n@@; $lc = $lc + $linenr; for (my $count = $linenr; $count <= $lc; $count++) { my $specifier; my $extension; my $qualifier; my $bad_specifier = ""; my $fmt = get_quoted_string($lines[$count - 1], raw_line($count, 0)); $fmt =~ s/%%//g; while ($fmt =~ /(\%[\*\d\.]*p(\w)(\w*))/g) { $specifier = $1; $extension = $2; $qualifier = $3; if ($extension !~ /[SsBKRraEehMmIiUDdgVCbGNOxtf]/ || ($extension eq "f" && defined $qualifier && $qualifier !~ /^w/)) { $bad_specifier = $specifier; last; } if ($extension eq "x" && !defined($stat_real)) { if (!defined($stat_real)) { $stat_real = get_stat_real($linenr, $lc); } WARN("VSPRINTF_SPECIFIER_PX", "Using vsprintf specifier '\%px' potentially exposes the kernel memory layout, if you don't really need the address please consider using '\%p'.\n" . "$here\n$stat_real\n"); } } if ($bad_specifier ne "") { my $stat_real = get_stat_real($linenr, $lc); my $ext_type = "Invalid"; my $use = ""; if ($bad_specifier =~ /p[Ff]/) { $use = " - use %pS instead"; $use =~ s/pS/ps/ if ($bad_specifier =~ /pf/); } WARN("VSPRINTF_POINTER_EXTENSION", "$ext_type vsprintf pointer extension '$bad_specifier'$use\n" . "$here\n$stat_real\n"); } } } # Check for misused memsets if ($perl_version_ok && defined $stat && $stat =~ /^\+(?:.*?)\bmemset\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*$FuncArg\s*\)/) { my $ms_addr = $2; my $ms_val = $7; my $ms_size = $12; if ($ms_size =~ /^(0x|)0$/i) { ERROR("MEMSET", "memset to 0's uses 0 as the 2nd argument, not the 3rd\n" . "$here\n$stat\n"); } elsif ($ms_size =~ /^(0x|)1$/i) { WARN("MEMSET", "single byte memset is suspicious. Swapped 2nd/3rd argument?\n" . "$here\n$stat\n"); } } # Check for memcpy(foo, bar, ETH_ALEN) that could be ether_addr_copy(foo, bar) # if ($perl_version_ok && # defined $stat && # $stat =~ /^\+(?:.*?)\bmemcpy\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*ETH_ALEN\s*\)/) { # if (WARN("PREFER_ETHER_ADDR_COPY", # "Prefer ether_addr_copy() over memcpy() if the Ethernet addresses are __aligned(2)\n" . "$here\n$stat\n") && # $fix) { # $fixed[$fixlinenr] =~ s/\bmemcpy\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*ETH_ALEN\s*\)/ether_addr_copy($2, $7)/; # } # } # Check for memcmp(foo, bar, ETH_ALEN) that could be ether_addr_equal*(foo, bar) # if ($perl_version_ok && # defined $stat && # $stat =~ /^\+(?:.*?)\bmemcmp\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*ETH_ALEN\s*\)/) { # WARN("PREFER_ETHER_ADDR_EQUAL", # "Prefer ether_addr_equal() or ether_addr_equal_unaligned() over memcmp()\n" . "$here\n$stat\n") # } # check for memset(foo, 0x0, ETH_ALEN) that could be eth_zero_addr # check for memset(foo, 0xFF, ETH_ALEN) that could be eth_broadcast_addr # if ($perl_version_ok && # defined $stat && # $stat =~ /^\+(?:.*?)\bmemset\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*ETH_ALEN\s*\)/) { # # my $ms_val = $7; # # if ($ms_val =~ /^(?:0x|)0+$/i) { # if (WARN("PREFER_ETH_ZERO_ADDR", # "Prefer eth_zero_addr over memset()\n" . "$here\n$stat\n") && # $fix) { # $fixed[$fixlinenr] =~ s/\bmemset\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*,\s*ETH_ALEN\s*\)/eth_zero_addr($2)/; # } # } elsif ($ms_val =~ /^(?:0xff|255)$/i) { # if (WARN("PREFER_ETH_BROADCAST_ADDR", # "Prefer eth_broadcast_addr() over memset()\n" . "$here\n$stat\n") && # $fix) { # $fixed[$fixlinenr] =~ s/\bmemset\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*,\s*ETH_ALEN\s*\)/eth_broadcast_addr($2)/; # } # } # } # typecasts on min/max could be min_t/max_t if ($perl_version_ok && defined $stat && $stat =~ /^\+(?:.*?)\b(min|max)\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\)/) { if (defined $2 || defined $7) { my $call = $1; my $cast1 = deparenthesize($2); my $arg1 = $3; my $cast2 = deparenthesize($7); my $arg2 = $8; my $cast; if ($cast1 ne "" && $cast2 ne "" && $cast1 ne $cast2) { $cast = "$cast1 or $cast2"; } elsif ($cast1 ne "") { $cast = $cast1; } else { $cast = $cast2; } WARN("MINMAX", "$call() should probably be ${call}_t($cast, $arg1, $arg2)\n" . "$here\n$stat\n"); } } # check usleep_range arguments if ($perl_version_ok && defined $stat && $stat =~ /^\+(?:.*?)\busleep_range\s*\(\s*($FuncArg)\s*,\s*($FuncArg)\s*\)/) { my $min = $1; my $max = $7; if ($min eq $max) { WARN("USLEEP_RANGE", "usleep_range should not use min == max args; see Documentation/timers/timers-howto.rst\n" . "$here\n$stat\n"); } elsif ($min =~ /^\d+$/ && $max =~ /^\d+$/ && $min > $max) { WARN("USLEEP_RANGE", "usleep_range args reversed, use min then max; see Documentation/timers/timers-howto.rst\n" . "$here\n$stat\n"); } } # check for naked sscanf if ($perl_version_ok && defined $stat && $line =~ /\bsscanf\b/ && ($stat !~ /$Ident\s*=\s*sscanf\s*$balanced_parens/ && $stat !~ /\bsscanf\s*$balanced_parens\s*(?:$Compare)/ && $stat !~ /(?:$Compare)\s*\bsscanf\s*$balanced_parens/)) { my $lc = $stat =~ tr@\n@@; $lc = $lc + $linenr; my $stat_real = get_stat_real($linenr, $lc); WARN("NAKED_SSCANF", "unchecked sscanf return value\n" . "$here\n$stat_real\n"); } # check for simple sscanf that should be kstrto<foo> if ($perl_version_ok && defined $stat && $line =~ /\bsscanf\b/) { my $lc = $stat =~ tr@\n@@; $lc = $lc + $linenr; my $stat_real = get_stat_real($linenr, $lc); if ($stat_real =~ /\bsscanf\b\s*\(\s*$FuncArg\s*,\s*("[^"]+")/) { my $format = $6; my $count = $format =~ tr@%@%@; if ($count == 1 && $format =~ /^"\%(?i:ll[udxi]|[udxi]ll|ll|[hl]h?[udxi]|[udxi][hl]h?|[hl]h?|[udxi])"$/) { WARN("SSCANF_TO_KSTRTO", "Prefer kstrto<type> to single variable sscanf\n" . "$here\n$stat_real\n"); } } } # check for new externs in .h files. if ($realfile =~ /\.h$/ && $line =~ /^\+\s*(extern\s+)$Type\s*$Ident\s*\(/s) { if (CHK("AVOID_EXTERNS", "extern prototypes should be avoided in .h files\n" . $herecurr) && $fix) { $fixed[$fixlinenr] =~ s/(.*)\bextern\b\s*(.*)/$1$2/; } } # check for new externs in .c files. if ($realfile =~ /\.c$/ && defined $stat && $stat =~ /^.\s*(?:extern\s+)?$Type\s+($Ident)(\s*)\(/s) { my $function_name = $1; my $paren_space = $2; my $s = $stat; if (defined $cond) { substr($s, 0, length($cond), ''); } if ($s =~ /^\s*;/) { WARN("AVOID_EXTERNS", "externs should be avoided in .c files\n" . $herecurr); } if ($paren_space =~ /\n/) { WARN("FUNCTION_ARGUMENTS", "arguments for function declarations should follow identifier\n" . $herecurr); } } elsif ($realfile =~ /\.c$/ && defined $stat && $stat =~ /^.\s*extern\s+/) { WARN("AVOID_EXTERNS", "externs should be avoided in .c files\n" . $herecurr); } # check for function declarations that have arguments without identifier names if (defined $stat && $stat =~ /^.\s*(?:extern\s+)?$Type\s*(?:$Ident|\(\s*\*\s*$Ident\s*\))\s*\(\s*([^{]+)\s*\)\s*;/s && $1 ne "void") { my $args = trim($1); while ($args =~ m/\s*($Type\s*(?:$Ident|\(\s*\*\s*$Ident?\s*\)\s*$balanced_parens)?)/g) { my $arg = trim($1); if ($arg =~ /^$Type$/ && $arg !~ /enum\s+$Ident$/) { WARN("FUNCTION_ARGUMENTS", "function definition argument '$arg' should also have an identifier name\n" . $herecurr); } } } # check for function definitions if ($perl_version_ok && defined $stat && $stat =~ /^.\s*(?:$Storage\s+)?$Type\s*($Ident)\s*$balanced_parens\s*{/s) { $context_function = $1; # check for multiline function definition with misplaced open brace my $ok = 0; my $cnt = statement_rawlines($stat); my $herectx = $here . "\n"; for (my $n = 0; $n < $cnt; $n++) { my $rl = raw_line($linenr, $n); $herectx .= $rl . "\n"; $ok = 1 if ($rl =~ /^[ \+]\{/); $ok = 1 if ($rl =~ /\{/ && $n == 0); last if $rl =~ /^[ \+].*\{/; } if (!$ok) { ERROR("OPEN_BRACE", "open brace '{' following function definitions go on the next line\n" . $herectx); } } # checks for new __setup's if ($rawline =~ /\b__setup\("([^"]*)"/) { my $name = $1; if (!grep(/$name/, @setup_docs)) { CHK("UNDOCUMENTED_SETUP", "__setup appears un-documented -- check Documentation/admin-guide/kernel-parameters.txt\n" . $herecurr); } } # check for pointless casting of alloc functions if ($line =~ /\*\s*\)\s*$allocFunctions\b/) { WARN("UNNECESSARY_CASTS", "unnecessary cast may hide bugs, see http://c-faq.com/malloc/mallocnocast.html\n" . $herecurr); } # alloc style # p = alloc(sizeof(struct foo), ...) should be p = alloc(sizeof(*p), ...) if ($perl_version_ok && $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*((?:kv|k|v)[mz]alloc(?:_node)?)\s*\(\s*(sizeof\s*\(\s*struct\s+$Lval\s*\))/) { CHK("ALLOC_SIZEOF_STRUCT", "Prefer $3(sizeof(*$1)...) over $3($4...)\n" . $herecurr); } # check for k[mz]alloc with multiplies that could be kmalloc_array/kcalloc if ($perl_version_ok && defined $stat && $stat =~ /^\+\s*($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)\s*,/) { my $oldfunc = $3; my $a1 = $4; my $a2 = $10; my $newfunc = "kmalloc_array"; $newfunc = "kcalloc" if ($oldfunc eq "kzalloc"); my $r1 = $a1; my $r2 = $a2; if ($a1 =~ /^sizeof\s*\S/) { $r1 = $a2; $r2 = $a1; } if ($r1 !~ /^sizeof\b/ && $r2 =~ /^sizeof\s*\S/ && !($r1 =~ /^$Constant$/ || $r1 =~ /^[A-Z_][A-Z0-9_]*$/)) { my $cnt = statement_rawlines($stat); my $herectx = get_stat_here($linenr, $cnt, $here); if (WARN("ALLOC_WITH_MULTIPLY", "Prefer $newfunc over $oldfunc with multiply\n" . $herectx) && $cnt == 1 && $fix) { $fixed[$fixlinenr] =~ s/\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)/$1 . ' = ' . "$newfunc(" . trim($r1) . ', ' . trim($r2)/e; } } } # check for krealloc arg reuse if ($perl_version_ok && $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*krealloc\s*\(\s*($Lval)\s*,/ && $1 eq $3) { WARN("KREALLOC_ARG_REUSE", "Reusing the krealloc arg is almost always a bug\n" . $herecurr); } # check for alloc argument mismatch if ($line =~ /\b(kcalloc|kmalloc_array)\s*\(\s*sizeof\b/) {