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author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-01-04 03:57:57 +0100 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-01-04 03:57:57 +0100 |
commit | 96d4f267e40f9509e8a66e2b39e8b95655617693 (patch) | |
tree | df03d142d405652392707b1b80c284d68d6ea6ab /drivers/char | |
parent | Merge tag 'locks-v4.21-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jl... (diff) | |
download | linux-96d4f267e40f9509e8a66e2b39e8b95655617693.tar.xz linux-96d4f267e40f9509e8a66e2b39e8b95655617693.zip |
Remove 'type' argument from access_ok() function
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.
It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.
A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.
This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.
There were a couple of notable cases:
- csky still had the old "verify_area()" name as an alias.
- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)
- microblaze used the type argument for a debug printout
but other than those oddities this should be a total no-op patch.
I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/char')
-rw-r--r-- | drivers/char/generic_nvram.c | 4 | ||||
-rw-r--r-- | drivers/char/mem.c | 4 | ||||
-rw-r--r-- | drivers/char/nwflash.c | 2 | ||||
-rw-r--r-- | drivers/char/pcmcia/cm4000_cs.c | 4 |
4 files changed, 7 insertions, 7 deletions
diff --git a/drivers/char/generic_nvram.c b/drivers/char/generic_nvram.c index 14e728fbb8a0..ff5394f47587 100644 --- a/drivers/char/generic_nvram.c +++ b/drivers/char/generic_nvram.c @@ -44,7 +44,7 @@ static ssize_t read_nvram(struct file *file, char __user *buf, unsigned int i; char __user *p = buf; - if (!access_ok(VERIFY_WRITE, buf, count)) + if (!access_ok(buf, count)) return -EFAULT; if (*ppos >= nvram_len) return 0; @@ -62,7 +62,7 @@ static ssize_t write_nvram(struct file *file, const char __user *buf, const char __user *p = buf; char c; - if (!access_ok(VERIFY_READ, buf, count)) + if (!access_ok(buf, count)) return -EFAULT; if (*ppos >= nvram_len) return 0; diff --git a/drivers/char/mem.c b/drivers/char/mem.c index 7b4e4de778e4..b08dc50f9f26 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -609,7 +609,7 @@ static ssize_t read_port(struct file *file, char __user *buf, unsigned long i = *ppos; char __user *tmp = buf; - if (!access_ok(VERIFY_WRITE, buf, count)) + if (!access_ok(buf, count)) return -EFAULT; while (count-- > 0 && i < 65536) { if (__put_user(inb(i), tmp) < 0) @@ -627,7 +627,7 @@ static ssize_t write_port(struct file *file, const char __user *buf, unsigned long i = *ppos; const char __user *tmp = buf; - if (!access_ok(VERIFY_READ, buf, count)) + if (!access_ok(buf, count)) return -EFAULT; while (count-- > 0 && i < 65536) { char c; diff --git a/drivers/char/nwflash.c b/drivers/char/nwflash.c index a284ae25e69a..76fb434068d4 100644 --- a/drivers/char/nwflash.c +++ b/drivers/char/nwflash.c @@ -167,7 +167,7 @@ static ssize_t flash_write(struct file *file, const char __user *buf, if (count > gbFlashSize - p) count = gbFlashSize - p; - if (!access_ok(VERIFY_READ, buf, count)) + if (!access_ok(buf, count)) return -EFAULT; /* diff --git a/drivers/char/pcmcia/cm4000_cs.c b/drivers/char/pcmcia/cm4000_cs.c index 809507bf8f1c..7a4eb86aedac 100644 --- a/drivers/char/pcmcia/cm4000_cs.c +++ b/drivers/char/pcmcia/cm4000_cs.c @@ -1445,11 +1445,11 @@ static long cmm_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) _IOC_DIR(cmd), _IOC_READ, _IOC_WRITE, size, cmd); if (_IOC_DIR(cmd) & _IOC_READ) { - if (!access_ok(VERIFY_WRITE, argp, size)) + if (!access_ok(argp, size)) goto out; } if (_IOC_DIR(cmd) & _IOC_WRITE) { - if (!access_ok(VERIFY_READ, argp, size)) + if (!access_ok(argp, size)) goto out; } rc = 0; |