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-rw-r--r--util/nvmutil/nvmutil.c606
1 files changed, 419 insertions, 187 deletions
diff --git a/util/nvmutil/nvmutil.c b/util/nvmutil/nvmutil.c
index b1d24bdc..35ea6757 100644
--- a/util/nvmutil/nvmutil.c
+++ b/util/nvmutil/nvmutil.c
@@ -163,17 +163,23 @@ also consider:
#include <time.h>
#include <unistd.h>
-typedef unsigned char u8;
+typedef unsigned char u8;
typedef unsigned short ushort;
-typedef unsigned int uint;
+typedef unsigned int uint;
+typedef unsigned long ulong;
/* type asserts */
typedef char static_assert_char_is_8_bits[(CHAR_BIT == 8) ? 1 : -1];
typedef char static_assert_char_is_1[(sizeof(char) == 1) ? 1 : -1];
-typedef char static_assert_uint8_is_1[(sizeof(u8) == 1) ? 1 : -1];
-typedef char static_assert_uint16_is_2[(sizeof(ushort) >= 2) ? 1 : -1];
+typedef char static_assert_u8_is_1[
+ (sizeof(u8) == 1) ? 1 : -1];
+typedef char static_assert_ushort_is_2[
+ (sizeof(ushort) >= 2) ? 1 : -1];
typedef char static_assert_short_is_2[(sizeof(short) >= 2) ? 1 : -1];
-typedef char static_assert_uint32_is_4[(sizeof(uint) >= 4) ? 1 : -1];
+typedef char static_assert_uint_is_4[
+ (sizeof(uint) >= 4) ? 1 : -1];
+typedef char static_assert_ulong_is_4[
+ (sizeof(ulong) >= 4) ? 1 : -1];
typedef char static_assert_int_ge_32[(sizeof(int) >= 4) ? 1 : -1];
typedef char static_assert_twos_complement[
((-1 & 3) == 3) ? 1 : -1
@@ -183,6 +189,9 @@ typedef char static_assert_twos_complement[
* We set _FILE_OFFSET_BITS 64, but we only handle
* files that are 128KB in size at a maximum, so we
* realistically only need 32-bit at a minimum.
+ *
+ * We set 64 anyway, because there's no reason not
+ * to, but some systems may ignore _FILE_OFFSET_BITS
*/
typedef char static_assert_off_t_is_32[(sizeof(off_t) >= 4) ? 1 : -1];
@@ -278,7 +287,7 @@ static void set_mac_nib(size_t mac_str_pos,
static ushort hextonum(char ch_s);
static ushort rhex(void);
static ushort fallback_rand(void);
-static unsigned long entropy_jitter(void);
+static ulong entropy_jitter(void);
static void write_mac_part(size_t partnum);
/*
@@ -323,29 +332,33 @@ static void check_bin(size_t a, const char *a_name);
*/
static void rw_gbe_file_part(size_t p, int rw_type,
const char *rw_type_str);
+static void check_written_part(size_t p);
+static void report_io_err_rw(void);
static u8 *gbe_mem_offset(size_t part, const char *f_op);
static off_t gbe_file_offset(size_t part, const char *f_op);
static off_t gbe_x_offset(size_t part, const char *f_op,
const char *d_type, off_t nsize, off_t ncmp);
-static ssize_t rw_file_exact(int fd, u8 *mem, size_t len,
+static ssize_t rw_gbe_file_exact(int fd, u8 *mem, size_t nrw,
off_t off, int rw_type);
+static ssize_t rw_file_exact(int fd, u8 *mem, size_t len,
+ off_t off, int rw_type, int loop_eagain, int loop_eintr);
static ssize_t rw_file_once(int fd, u8 *mem, size_t len,
- off_t off, int rw_type, size_t rc);
-static ssize_t do_rw(int fd,
- u8 *mem, size_t len, off_t off, int rw_type);
+ off_t off, int rw_type, size_t rc, int loop_eagain,
+ int loop_eintr);
static ssize_t prw(int fd, void *mem, size_t nrw,
- off_t off, int rw_type);
-static off_t lseek_eintr(int fd, off_t off, int whence);
-static int io_args(int fd, void *mem, size_t nrw,
- off_t off, int rw_type);
+ off_t off, int rw_type, int loop_eagain, int loop_eintr);
+static int rw_over_nrw(ssize_t r, size_t nrw);
+static off_t lseek_loop(int fd, off_t off,
+ int whence, int loop_eagain, int loop_eintr);
+static int try_err(int loop_err, int errval);
/*
* Error handling and cleanup
*/
+static int close_files(void);
static void err(int nvm_errval, const char *msg, ...);
-static void close_files(void);
static const char *getnvmprogname(void);
-static void usage(u8 usage_exit);
+static void usage(int usage_exit);
/*
* Sizes in bytes:
@@ -396,8 +409,9 @@ static const char *rname = NULL;
*
* The code will handle this properly.
*/
-static u8 buf[GBE_FILE_SIZE];
-static u8 pad[GBE_PART_SIZE]; /* the file that wouldn't die */
+static u8 real_buf[GBE_FILE_SIZE];
+static u8 pad[GBE_FILE_SIZE]; /* the file that wouldn't die */
+static u8 *buf = real_buf;
static ushort mac_buf[3];
static off_t gbe_file_size;
@@ -592,6 +606,13 @@ typedef char bool_part_invert[(PART_INVERT==1)?1:-1];
static int use_prng = 0;
+static int io_err_gbe = 0;
+static int rw_check_err_read[] = {0, 0};
+static int rw_check_partial_read[] = {0, 0};
+static int rw_check_bad_part[] = {0, 0};
+
+static int post_rw_checksum[] = {0, 0};
+
int
main(int argc, char *argv[])
{
@@ -663,10 +684,29 @@ main(int argc, char *argv[])
run_cmd(cmd_index);
- if (command[cmd_index].flags == O_RDWR)
+ if (command[cmd_index].flags == O_RDWR) {
+
write_gbe_file();
- close_files();
+ /*
+ * We may otherwise read from
+ * cache, so we must sync.
+ */
+ if (fsync(gbe_fd) == -1)
+ err(errno, "%s: fsync (pre-verification)",
+ fname);
+
+ check_written_part(0);
+ check_written_part(1);
+
+ report_io_err_rw();
+
+ if (io_err_gbe)
+ err(EIO, "%s: bad write", fname);
+ }
+
+ if (close_files() == -1)
+ err(EIO, "%s: close", fname);
return EXIT_SUCCESS;
}
@@ -696,19 +736,19 @@ sanitize_command_index(size_t c)
if (command[c].argc < 3)
err(EINVAL, "cmd index %lu: argc below 3, %d",
- (unsigned long)c, command[c].argc);
+ (ulong)c, command[c].argc);
if (command[c].str == NULL)
err(EINVAL, "cmd index %lu: NULL str",
- (unsigned long)c);
+ (ulong)c);
if (*command[c].str == '\0')
err(EINVAL, "cmd index %lu: empty str",
- (unsigned long)c);
+ (ulong)c);
if (xstrxlen(command[c].str, MAX_CMD_LEN + 1) >
MAX_CMD_LEN) {
err(EINVAL, "cmd index %lu: str too long: %s",
- (unsigned long)c, command[c].str);
+ (ulong)c, command[c].str);
}
mod_type = command[c].set_modified;
@@ -736,12 +776,12 @@ sanitize_command_index(size_t c)
break;
default:
err(EINVAL, "Unsupported rw_size: %lu",
- (unsigned long)gbe_rw_size);
+ (ulong)gbe_rw_size);
}
if (gbe_rw_size > GBE_PART_SIZE)
err(EINVAL, "rw_size larger than GbE part: %lu",
- (unsigned long)gbe_rw_size);
+ (ulong)gbe_rw_size);
if (command[c].flags != O_RDONLY &&
command[c].flags != O_RDWR)
@@ -794,13 +834,13 @@ set_cmd_args(int argc, char *argv[])
static size_t
conv_argv_part_num(const char *part_str)
{
- unsigned char ch;
+ u8 ch;
if (part_str[0] == '\0' || part_str[1] != '\0')
err(EINVAL, "Partnum string '%s' wrong length", part_str);
/* char signedness is implementation-defined */
- ch = (unsigned char)part_str[0];
+ ch = (u8)part_str[0];
if (ch < '0' || ch > '1')
err(EINVAL, "Bad part number (%c)", ch);
@@ -824,7 +864,7 @@ xstrxcmp(const char *a, const char *b, size_t maxlen)
for (i = 0; i < maxlen; i++) {
if (a[i] != b[i])
- return (unsigned char)a[i] - (unsigned char)b[i];
+ return (u8)a[i] - (u8)b[i];
if (a[i] == '\0')
return 0;
@@ -852,7 +892,7 @@ open_dev_urandom(void)
/* fallback on VERY VERY VERY old unix */
use_prng = 1;
- srand((unsigned)(time(NULL) ^ getpid()));
+ srand((uint)(time(NULL) ^ getpid()));
}
static void
@@ -970,7 +1010,7 @@ read_checksums(void)
if (num_invalid >= max_invalid) {
if (max_invalid == 1)
err(ECANCELED, "%s: part %lu has a bad checksum",
- fname, (unsigned long)part);
+ fname, (ulong)part);
err(ECANCELED, "%s: No valid checksum found in file",
fname);
}
@@ -1001,7 +1041,7 @@ check_command_num(size_t c)
{
if (!valid_command(c))
err(EINVAL, "Invalid run_cmd arg: %lu",
- (unsigned long)c);
+ (ulong)c);
}
static u8
@@ -1012,7 +1052,7 @@ valid_command(size_t c)
if (c != command[c].chk)
err(EINVAL, "Invalid cmd chk value (%lu) vs arg: %lu",
- (unsigned long)command[c].chk, (unsigned long)c);
+ (ulong)command[c].chk, (ulong)c);
return 1;
}
@@ -1126,14 +1166,14 @@ set_mac_nib(size_t mac_str_pos,
static ushort
hextonum(char ch_s)
{
- unsigned char ch = (unsigned char)ch_s;
+ u8 ch = (u8)ch_s;
- if ((unsigned)(ch - '0') <= 9)
+ if ((uint)(ch - '0') <= 9)
return ch - '0';
ch |= 0x20;
- if ((unsigned)(ch - 'a') <= 5)
+ if ((uint)(ch - 'a') <= 5)
return ch - 'a' + 10;
if (ch == '?' || ch == 'x')
@@ -1152,7 +1192,7 @@ rhex(void)
if (!n) {
n = sizeof(rnum);
- if (rw_file_exact(urandom_fd, rnum, n, 0, IO_READ) == -1)
+ if (rw_file_exact(urandom_fd, rnum, n, 0, IO_READ, 0, 1) == -1)
err(errno, "Randomisation failed");
}
@@ -1163,15 +1203,15 @@ static ushort
fallback_rand(void)
{
struct timeval tv;
- unsigned long mix;
- static unsigned long counter = 0;
+ ulong mix;
+ static ulong counter = 0;
gettimeofday(&tv, NULL);
- mix = (unsigned long)tv.tv_sec
- ^ (unsigned long)tv.tv_usec
- ^ (unsigned long)getpid()
- ^ (unsigned long)&mix
+ mix = (ulong)tv.tv_sec
+ ^ (ulong)tv.tv_usec
+ ^ (ulong)getpid()
+ ^ (ulong)&mix
^ counter++
^ entropy_jitter();
@@ -1179,18 +1219,18 @@ fallback_rand(void)
* Stack addresses can vary between
* calls, thus increasing entropy.
*/
- mix ^= (unsigned long)&mix;
- mix ^= (unsigned long)&tv;
- mix ^= (unsigned long)&counter;
+ mix ^= (ulong)&mix;
+ mix ^= (ulong)&tv;
+ mix ^= (ulong)&counter;
return (ushort)(mix & 0xf);
}
-static unsigned long
+static ulong
entropy_jitter(void)
{
struct timeval a, b;
- unsigned long mix = 0;
+ ulong mix = 0;
long mix_diff;
int i;
@@ -1207,8 +1247,8 @@ entropy_jitter(void)
if (mix_diff < 0)
mix_diff = -mix_diff;
- mix ^= (unsigned long)(mix_diff);
- mix ^= (unsigned long)&mix;
+ mix ^= (ulong)(mix_diff);
+ mix ^= (ulong)&mix;
}
return mix;
@@ -1227,7 +1267,7 @@ write_mac_part(size_t partnum)
set_nvm_word(w, partnum, mac_buf[w]);
printf("Wrote MAC address to part %lu: ",
- (unsigned long)partnum);
+ (ulong)partnum);
print_mac_from_nvm(partnum);
}
@@ -1244,11 +1284,11 @@ cmd_helper_dump(void)
fprintf(stderr,
"BAD checksum %04x in part %lu (expected %04x)\n",
nvm_word(NVM_CHECKSUM_WORD, partnum),
- (unsigned long)partnum,
+ (ulong)partnum,
calculated_checksum(partnum));
printf("MAC (part %lu): ",
- (unsigned long)partnum);
+ (ulong)partnum);
print_mac_from_nvm(partnum);
hexdump(partnum);
}
@@ -1263,8 +1303,8 @@ print_mac_from_nvm(size_t partnum)
for (c = 0; c < 3; c++) {
val16 = nvm_word(c, partnum);
printf("%02x:%02x",
- (unsigned int)(val16 & 0xff),
- (unsigned int)(val16 >> 8));
+ (uint)(val16 & 0xff),
+ (uint)(val16 >> 8));
if (c == 2)
printf("\n");
else
@@ -1280,14 +1320,14 @@ hexdump(size_t partnum)
ushort val16;
for (row = 0; row < 8; row++) {
- printf("%08lx ", (unsigned long)((size_t)row << 4));
+ printf("%08lx ", (ulong)((size_t)row << 4));
for (c = 0; c < 8; c++) {
val16 = nvm_word((row << 3) + c, partnum);
if (c == 4)
printf(" ");
printf(" %02x %02x",
- (unsigned int)(val16 & 0xff),
- (unsigned int)(val16 >> 8));
+ (uint)(val16 & 0xff),
+ (uint)(val16 >> 8));
}
printf("\n");
}
@@ -1320,26 +1360,9 @@ cmd_helper_cat(void)
static void
gbe_cat_buf(u8 *b)
{
- ssize_t rval;
-
- while (1) {
- rval = rw_file_exact(STDOUT_FILENO, b,
- GBE_PART_SIZE, 0, IO_WRITE);
-
- if (rval >= 0) {
- /*
- * A partial write is especially
- * fatal, as it should already be
- * prevented in rw_file_exact().
- */
- if ((size_t)rval != GBE_PART_SIZE)
- err(EIO, "stdout: cat: Partial write");
- break;
- }
-
- if (errno != EAGAIN)
- err(errno, "stdout: cat");
- }
+ if (rw_file_exact(STDOUT_FILENO, b,
+ GBE_PART_SIZE, 0, IO_WRITE, 1, 1) < 0)
+ err(errno, "stdout: cat");
}
static void
@@ -1480,7 +1503,7 @@ check_nvm_bound(size_t c, size_t p)
if (c >= NVM_WORDS)
err(ECANCELED, "check_nvm_bound: out of bounds %lu",
- (unsigned long)c);
+ (ulong)c);
}
static void
@@ -1488,21 +1511,23 @@ check_bin(size_t a, const char *a_name)
{
if (a > 1)
err(EINVAL, "%s must be 0 or 1, but is %lu",
- a_name, (unsigned long)a);
+ a_name, (ulong)a);
}
static void
rw_gbe_file_part(size_t p, int rw_type,
const char *rw_type_str)
{
+ ssize_t r;
size_t gbe_rw_size = command[cmd_index].rw_size;
u8 invert = command[cmd_index].invert;
u8 *mem_offset;
+ off_t file_offset;
if (rw_type < IO_PREAD || rw_type > IO_PWRITE)
err(errno, "%s: %s: part %lu: invalid rw_type, %d",
- fname, rw_type_str, (unsigned long)p, rw_type);
+ fname, rw_type_str, (ulong)p, rw_type);
if (rw_type == IO_PWRITE)
invert = 0;
@@ -1512,12 +1537,116 @@ rw_gbe_file_part(size_t p, int rw_type,
* E.g. read from p0 (file) to p1 (mem).
*/
mem_offset = gbe_mem_offset(p ^ invert, rw_type_str);
+ file_offset = (off_t)gbe_file_offset(p, rw_type_str);
- if (rw_file_exact(gbe_fd, mem_offset,
- gbe_rw_size, gbe_file_offset(p, rw_type_str),
- rw_type) == -1)
+ r = rw_gbe_file_exact(gbe_fd, mem_offset,
+ gbe_rw_size, file_offset, rw_type);
+
+ if (r == -1)
err(errno, "%s: %s: part %lu",
- fname, rw_type_str, (unsigned long)p);
+ fname, rw_type_str, (ulong)p);
+
+ if ((size_t)r != gbe_rw_size)
+ err(EIO, "%s: partial %s: part %lu",
+ fname, rw_type_str, (ulong)p);
+}
+
+static void
+check_written_part(size_t p)
+{
+ ssize_t r;
+ size_t gbe_rw_size;
+ u8 *mem_offset;
+ off_t file_offset;
+ u8 *buf_restore;
+
+ if (!part_modified[p])
+ return;
+
+ gbe_rw_size = command[cmd_index].rw_size;
+
+ /* invert not needed for pwrite */
+ mem_offset = gbe_mem_offset(p, "pwrite");
+ file_offset = (off_t)gbe_file_offset(p, "pwrite");
+
+ memset(pad, 0xff, sizeof(pad));
+
+ r = rw_gbe_file_exact(gbe_fd, pad,
+ gbe_rw_size, file_offset, IO_PREAD);
+
+ if (r == -1)
+ rw_check_err_read[p] = io_err_gbe = 1;
+ else if ((size_t)r != gbe_rw_size)
+ rw_check_partial_read[p] = io_err_gbe = 1;
+ else if (memcmp(mem_offset, pad, gbe_rw_size) != 0)
+ rw_check_bad_part[p] = io_err_gbe = 1;
+
+ if (rw_check_err_read[p] ||
+ rw_check_partial_read[p])
+ return;
+
+ /*
+ * We only load one part on-file, into memory but
+ * always at offset zero, for post-write checks.
+ * That's why we hardcode good_checksum(0).
+ */
+ buf_restore = buf;
+ buf = pad;
+ post_rw_checksum[p] = good_checksum(0);
+ buf = buf_restore;
+}
+
+static void
+report_io_err_rw(void)
+{
+ size_t p;
+
+ if (!io_err_gbe)
+ return;
+
+ for (p = 0; p < 2; p++) {
+ if (!part_modified[p])
+ continue;
+
+ if (rw_check_err_read[p])
+ fprintf(stderr,
+ "%s: pread: p%lu (post-verification)\n",
+ fname, (ulong)p);
+ if (rw_check_partial_read[p])
+ fprintf(stderr,
+ "%s: partial pread: p%lu (post-verification)\n",
+ fname, (ulong)p);
+ if (rw_check_bad_part[p])
+ fprintf(stderr,
+ "%s: pwrite: corrupt write on p%lu\n",
+ fname, (ulong)p);
+
+ if (rw_check_err_read[p] ||
+ rw_check_partial_read[p]) {
+ fprintf(stderr,
+ "%s: p%lu: skipped checksum verification "
+ "(because read failed)\n",
+ fname, (ulong)p);
+
+ continue;
+ }
+
+ fprintf(stderr, "%s: ", fname);
+
+ if (post_rw_checksum[p])
+ fprintf(stderr, "GOOD");
+ else
+ fprintf(stderr, "BAD");
+
+ fprintf(stderr, " checksum in p%lu on-disk.\n",
+ (ulong)p);
+
+ if (post_rw_checksum[p]) {
+ fprintf(stderr,
+ " This does NOT mean it's safe. it may be\n"
+ " salvageable if you use the cat feature.\n");
+ }
+ }
}
/*
@@ -1571,6 +1700,34 @@ gbe_x_offset(size_t p, const char *f_op, const char *d_type,
return off;
}
+static ssize_t
+rw_gbe_file_exact(int fd, u8 *mem, size_t nrw,
+ off_t off, int rw_type)
+{
+ if (mem == NULL)
+ goto err_rw_gbe_file_exact;
+
+ if (mem != (void *)pad
+ && mem != (void *)rnum
+ && (mem < buf || mem >= (buf + GBE_FILE_SIZE)))
+ goto err_rw_gbe_file_exact;
+
+ if (off < 0 || off >= gbe_file_size)
+ goto err_rw_gbe_file_exact;
+
+ if (nrw > (size_t)(gbe_file_size - off))
+ goto err_rw_gbe_file_exact;
+
+ if (nrw > GBE_PART_SIZE)
+ goto err_rw_gbe_file_exact;
+
+ return rw_file_exact(fd, mem, nrw, off, rw_type, 0, 1);
+
+err_rw_gbe_file_exact:
+ errno = EIO;
+ return -1;
+}
+
/*
* Read or write the exact contents of a file,
* along with a buffer, (if applicable) offset,
@@ -1590,19 +1747,25 @@ gbe_x_offset(size_t p, const char *f_op, const char *d_type,
*/
static ssize_t
rw_file_exact(int fd, u8 *mem, size_t nrw,
- off_t off, int rw_type)
+ off_t off, int rw_type, int loop_eagain,
+ int loop_eintr)
{
ssize_t rv;
size_t rc;
- if (io_args(fd, mem, nrw, off, rw_type) == -1) {
- errno = EIO;
- return -1;
- }
-
for (rc = 0, rv = 0; rc < nrw; ) {
- if ((rv = rw_file_once(fd, mem, nrw, off, rw_type, rc)) <= 0)
+ if ((rv = rw_file_once(fd, mem, nrw, off, rw_type, rc,
+ loop_eagain, loop_eintr)) < 0)
+ return -1;
+
+ /* rw_file_once never returns
+ zero, but it's still logically
+ incorrect not to handle it here */
+
+ if (rv == 0) {
+ errno = EIO;
return -1;
+ }
rc += (size_t)rv;
}
@@ -1611,31 +1774,38 @@ rw_file_exact(int fd, u8 *mem, size_t nrw,
}
/*
- * May not return all requested bytes (len).
+ * Helper function for rw_file_exact, that
+ * also does extra error handling pertaining
+ * to GbE file offsets.
+ *
+ * May not return all requested bytes (nrw).
* Use rw_file_exact for guaranteed length.
+ *
+ * This function will never return zero.
+ * It will only return below (error),
+ * or above (success). On error, -1 is
+ * returned and errno is set accordingly.
*/
static ssize_t
rw_file_once(int fd, u8 *mem, size_t nrw,
- off_t off, int rw_type, size_t rc)
+ off_t off, int rw_type, size_t rc,
+ int loop_eagain, int loop_eintr)
{
ssize_t rv;
size_t retries_on_zero = 0;
size_t max_retries = 10;
- if (io_args(fd, mem, nrw, off, rw_type) == -1)
+ if (mem == NULL)
goto err_rw_file_once;
read_again:
- rv = do_rw(fd, mem + rc, nrw - rc, off + rc, rw_type);
-
- if (rv < 0 && errno == EINTR)
- goto read_again;
+ rv = prw(fd, mem + rc, nrw - rc, off + rc, rw_type,
+ loop_eagain, loop_eintr);
if (rv < 0)
return -1;
- if ((size_t)rv > SSIZE_MAX /* theoretical buggy libc */
- || (size_t)rv > (nrw - rc))/* don't overflow */
+ if ((size_t)rv > (nrw - rc))/* don't overflow */
goto err_rw_file_once;
if (rv != 0)
@@ -1649,28 +1819,9 @@ err_rw_file_once:
return -1;
}
-static ssize_t
-do_rw(int fd, u8 *mem,
- size_t nrw, off_t off, int rw_type)
-{
- if (io_args(fd, mem, nrw, off, rw_type) == -1)
- goto err_do_rw;
-
- if (rw_type == IO_READ)
- return read(fd, mem, nrw);
-
- if (rw_type == IO_WRITE)
- return write(fd, mem, nrw);
-
- if (rw_type == IO_PREAD || rw_type == IO_PWRITE)
- return prw(fd, mem, nrw, off, rw_type);
-
-err_do_rw:
- errno = EIO;
- return -1;
-}
-
/*
+ * prw() - portable read-write
+ *
* This implements a portable analog of pwrite()
* and pread() - note that this version is not
* thread-safe (race conditions are possible on
@@ -1678,25 +1829,64 @@ err_do_rw:
*
* This limitation is acceptable, since nvmutil is
* single-threaded. Portability is the main goal.
+ *
+ * A fallback is provided for regular read/write.
+ * rw_type can be IO_READ, IO_WRITE, IO_PREAD
+ * or IO_PWRITE
+ *
+ * loop_eagain does a retry loop on EAGAIN if set
+ * loop_eintr does a retry loop on EINTR if set
+ *
+ * Unlike the bare syscalls, prw() does security
+ * checks e.g. checks NULL strings, checks bounds,
+ * also mitigates a few theoretical libc bugs.
+ * It is designed for extremely safe single-threaded
+ * I/O on applications that need it.
*/
+
static ssize_t
prw(int fd, void *mem, size_t nrw,
- off_t off, int rw_type)
+ off_t off, int rw_type,
+ int loop_eagain, int loop_eintr)
{
off_t off_orig;
ssize_t r;
int saved_errno;
- int prw_type;
int flags;
+ int positional_rw;
- if (io_args(fd, mem, nrw, off, rw_type) == -1)
+ if (mem == NULL)
goto err_prw;
- prw_type = rw_type ^ IO_PREAD;
-
- if ((unsigned int)prw_type > IO_WRITE)
+ if (fd < 0
+ || off < 0
+ || !nrw /* prevent zero read request */
+ || nrw > (size_t)SSIZE_MAX /* prevent overflow */
+ || (uint)rw_type > IO_PWRITE)
goto err_prw;
+ r = -1;
+
+ if (rw_type >= IO_PREAD)
+ positional_rw = 1; /* pread/pwrite */
+ else
+ positional_rw = 0; /* read/write */
+
+try_rw_again:
+
+ if (!positional_rw) {
+ if (rw_type == IO_WRITE)
+ r = write(fd, mem, nrw);
+ else if (rw_type == IO_READ)
+ r = read(fd, mem, nrw);
+
+ if (r == -1 && (errno == try_err(loop_eintr, EINTR)
+ || errno == try_err(loop_eagain, EAGAIN)))
+ goto try_rw_again;
+
+ return rw_over_nrw(r, nrw);
+ }
+
flags = fcntl(fd, F_GETFL);
if (flags == -1)
return -1;
@@ -1710,89 +1900,147 @@ prw(int fd, void *mem, size_t nrw,
if (flags & O_APPEND)
goto err_prw;
- if ((off_orig = lseek_eintr(fd, (off_t)0, SEEK_CUR)) == (off_t)-1)
- return -1;
-
- if (lseek_eintr(fd, off, SEEK_SET) == (off_t)-1)
- return -1;
+ if ((off_orig = lseek_loop(fd, (off_t)0, SEEK_CUR,
+ loop_eagain, loop_eintr)) == (off_t)-1)
+ r = -1;
+ else if (lseek_loop(fd, off, SEEK_SET,
+ loop_eagain, loop_eintr) == (off_t)-1)
+ r = -1;
do {
- r = do_rw(fd, mem, nrw, off, prw_type);
- } while (r < 0 && errno == EINTR);
+ if (rw_type == IO_PREAD)
+ r = read(fd, mem, nrw);
+ else if (rw_type == IO_PWRITE)
+ r = write(fd, mem, nrw);
- saved_errno = errno;
- if (lseek_eintr(fd, off_orig, SEEK_SET) == (off_t)-1) {
- if (r < 0)
- errno = saved_errno;
+ r = rw_over_nrw(r, nrw);
+ } while (r == -1 &&
+ (errno == try_err(loop_eintr, EINTR)
+ || errno == try_err(loop_eagain, EAGAIN)));
+ saved_errno = errno;
+ if (lseek_loop(fd, off_orig, SEEK_SET,
+ loop_eagain, loop_eintr) == (off_t)-1) {
+ errno = saved_errno;
return -1;
}
errno = saved_errno;
- return r;
+ return rw_over_nrw(r, nrw);
err_prw:
errno = EIO;
return -1;
}
+/*
+ * POSIX can say whatever it wants.
+ * specification != implementation
+ */
static int
-io_args(int fd, void *mem, size_t nrw,
- off_t off, int rw_type)
+rw_over_nrw(ssize_t r, size_t nrw)
{
- if (mem == NULL)
- goto err_io_args;
-
- if (mem != (void *)pad
- && mem != (void *)rnum
- && (mem < (void *)buf || mem >= (void *)(buf + GBE_FILE_SIZE)))
- goto err_io_args;
-
- if (off < 0 || off >= gbe_file_size)
- goto err_io_args;
+ if (r == -1)
+ return r;
- if (nrw > (size_t)(gbe_file_size - off))
- goto err_io_args;
+ if ((size_t)r > SSIZE_MAX) {
+ /*
+ * Theoretical buggy libc
+ * check. Extremely academic.
+ *
+ * Specifications never
+ * allow this return value
+ * to exceed SSIZE_MAX, but
+ * spec != implementation
+ *
+ * Check this after using
+ * [p]read() or [p]write()
+ */
+ goto err_rw_over_nrw;
+ }
- if (nrw > GBE_PART_SIZE)
- goto err_io_args;
+ /*
+ * Theoretical buggy libc:
+ * Should never return a number of
+ * bytes above the requested length.
+ */
+ if ((size_t)r > nrw)
+ goto err_rw_over_nrw;
- if (fd < 0
- || !nrw /* prevent zero read request */
- || nrw > (size_t)SSIZE_MAX /* prevent overflow */
- || (unsigned int)rw_type > IO_PWRITE)
- goto err_io_args;
+ return r;
- return 0;
+err_rw_over_nrw:
-err_io_args:
errno = EIO;
return -1;
}
static off_t
-lseek_eintr(int fd, off_t off, int whence)
+lseek_loop(int fd, off_t off, int whence,
+ int loop_eagain, int loop_eintr)
{
- off_t old;
+ off_t old = -1;
do {
old = lseek(fd, off, whence);
- } while (old == (off_t)-1 && errno == EINTR);
+ } while (old == (off_t)-1 && (
+ errno == try_err(loop_eintr, EINTR) ||
+ errno == try_err(loop_eagain, EAGAIN)));
return old;
}
+static int
+try_err(int loop_err, int errval)
+{
+ if (loop_err)
+ return errval;
+
+ /* errno is never negative,
+ so functions checking it
+ can use it accordingly */
+ return -1;
+}
+
+static int
+close_files(void)
+{
+ int close_err_gbe = 0;
+ int close_err_rand = 0;
+ int saved_errno = errno;
+
+ if (gbe_fd > -1) {
+ if (close(gbe_fd) == -1)
+ close_err_gbe = errno;
+ gbe_fd = -1;
+ }
+
+ if (urandom_fd > -1) {
+ if (close(urandom_fd) == -1)
+ close_err_rand = errno;
+ urandom_fd = -1;
+ }
+
+ if (saved_errno)
+ errno = saved_errno;
+
+ if (close_err_gbe || close_err_rand)
+ return -1;
+
+ return 0;
+}
+
static void
err(int nvm_errval, const char *msg, ...)
{
va_list args;
- if (nvm_errval >= 0) {
- close_files();
- errno = nvm_errval;
- }
if (errno <= 0)
errno = ECANCELED;
+ if (!errno)
+ errno = nvm_errval;
+
+ (void)close_files();
fprintf(stderr, "%s: ", getnvmprogname());
@@ -1806,22 +2054,6 @@ err(int nvm_errval, const char *msg, ...)
exit(EXIT_FAILURE);
}
-static void
-close_files(void)
-{
- if (gbe_fd > -1) {
- if (close(gbe_fd) == -1)
- err(-1, "%s: close failed", fname);
- gbe_fd = -1;
- }
-
- if (urandom_fd > -1) {
- if (close(urandom_fd) == -1)
- err(-1, "%s: close failed", rname);
- urandom_fd = -1;
- }
-}
-
static const char *
getnvmprogname(void)
{
@@ -1839,7 +2071,7 @@ getnvmprogname(void)
}
static void
-usage(u8 usage_exit)
+usage(int usage_exit)
{
const char *util = getnvmprogname();