| Message ID | 1457333940-13076-1-git-send-email-shawn.lin@rock-chips.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Mar 7, 2016 at 1:59 PM, Shawn Lin <shawn.lin@rock-chips.com> wrote: > We should return -EINVAL if cmd is not MMC_IOC_CMD or MMC_IOC_MULTI_CMD, > otherwise blkdev_roset will return -EPERM. > > Android-adb calls make_block_device_writable with ioctl(BLKROSET), which > will return error, make remount failed: > remount of /system failed; > couldn't make block device writable: Operation not permitted > > openat(AT_FDCWD, "/dev/block/platform/ff420000.dwmmc/by-name/system", O_RDONLY) = 3 > ioctl(3, BLKROSET, 0) = -1 EPERM (Operation not permitted) > > Fixes: a5f5774c55a2 ("mmc: block: Add new ioctl to send multi commands") > Cc: stable@vger.kernel.org > Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> Ulf, We're hitting this as well, and Shawn's patch seems to fix it for me. Tested-by: John Stultz <john.stultz@linaro.org> Thanks Shawn! -john -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 07/03/16 06:59, Shawn Lin wrote: > We should return -EINVAL if cmd is not MMC_IOC_CMD or MMC_IOC_MULTI_CMD, > otherwise blkdev_roset will return -EPERM. > > Android-adb calls make_block_device_writable with ioctl(BLKROSET), which > will return error, make remount failed: > remount of /system failed; > couldn't make block device writable: Operation not permitted I think you should elaborate here why the behaviour between -EINVAL and -EPERM is different as they are both errors. In other words, add your comment about how the ADB code is checking for a supported command. > openat(AT_FDCWD, "/dev/block/platform/ff420000.dwmmc/by-name/system", O_RDONLY) = 3 > ioctl(3, BLKROSET, 0) = -1 EPERM (Operation not permitted) > > Fixes: a5f5774c55a2 ("mmc: block: Add new ioctl to send multi commands") > Cc: stable@vger.kernel.org > Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> > --- > > drivers/mmc/card/block.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c > index 47bc87d..170f099 100644 > --- a/drivers/mmc/card/block.c > +++ b/drivers/mmc/card/block.c > @@ -688,6 +688,9 @@ cmd_err: > static int mmc_blk_ioctl(struct block_device *bdev, fmode_t mode, > unsigned int cmd, unsigned long arg) > { > + if (cmd != MMC_IOC_CMD && cmd != MMC_IOC_MULTI_CMD) > + return -EINVAL; > + > /* > * The caller must have CAP_SYS_RAWIO, and must be calling this on the > * whole block device, not on a partition. This prevents overspray The change is fine with me, but I agree with Seshagiri's comment that instead of the above, move the following test to the mmc_blk_ioctl_cmd and mmc_blk_ioctl_multi_cmd functions: if ((!capable(CAP_SYS_RAWIO)) || (bdev != bdev->bd_contains)) return -EPERM; There is a case statement that then would return -EINVAL if the command is not supported. If you look at V3 of the patch "mmc: block: Add new ioctl to send multi commands" [0] this is how we had it and only in V4 (the final version) did we move it. Cheers Jon [0] http://marc.info/?l=linux-mmc&m=144224289716299&w=2 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 2016/3/9 18:50, Jon Hunter wrote: > > On 07/03/16 06:59, Shawn Lin wrote: >> We should return -EINVAL if cmd is not MMC_IOC_CMD or MMC_IOC_MULTI_CMD, >> otherwise blkdev_roset will return -EPERM. >> >> Android-adb calls make_block_device_writable with ioctl(BLKROSET), which >> will return error, make remount failed: >> remount of /system failed; >> couldn't make block device writable: Operation not permitted > > I think you should elaborate here why the behaviour between -EINVAL and > -EPERM is different as they are both errors. In other words, add your > comment about how the ADB code is checking for a supported command. yep. So if need to send v2 after comment from Ulf, I will add more into commit-msg. > >> openat(AT_FDCWD, "/dev/block/platform/ff420000.dwmmc/by-name/system", O_RDONLY) = 3 >> ioctl(3, BLKROSET, 0) = -1 EPERM (Operation not permitted) >> >> Fixes: a5f5774c55a2 ("mmc: block: Add new ioctl to send multi commands") >> Cc: stable@vger.kernel.org >> Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> >> --- >> >> drivers/mmc/card/block.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c >> index 47bc87d..170f099 100644 >> --- a/drivers/mmc/card/block.c >> +++ b/drivers/mmc/card/block.c >> @@ -688,6 +688,9 @@ cmd_err: >> static int mmc_blk_ioctl(struct block_device *bdev, fmode_t mode, >> unsigned int cmd, unsigned long arg) >> { >> + if (cmd != MMC_IOC_CMD && cmd != MMC_IOC_MULTI_CMD) >> + return -EINVAL; >> + >> /* >> * The caller must have CAP_SYS_RAWIO, and must be calling this on the >> * whole block device, not on a partition. This prevents overspray > > The change is fine with me, but I agree with Seshagiri's comment that > instead of the above, move the following test to the mmc_blk_ioctl_cmd > and mmc_blk_ioctl_multi_cmd functions: > > if ((!capable(CAP_SYS_RAWIO)) || (bdev != bdev->bd_contains)) > return -EPERM; > right, and both are ok to me :). Adding this check for mmc_blk_ioctl_cmd and mmc_blk_ioctl_multi_cmd respectively may also looks like we produce two some code sections that do the same thing. I think it depends on how Ulf want the solution to be? Let's wait for Ulf' comment. > There is a case statement that then would return -EINVAL if the command > is not supported. > > If you look at V3 of the patch "mmc: block: Add new ioctl to send multi > commands" [0] this is how we had it and only in V4 (the final version) > did we move it. yes, I read V3 and V4 both to see how the patch was going. Thanks for sharing it. > > Cheers > Jon > > [0] http://marc.info/?l=linux-mmc&m=144224289716299&w=2 > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 9 March 2016 at 14:51, Shawn Lin <shawn.lin@kernel-upstream.org> wrote: > On 2016/3/9 18:50, Jon Hunter wrote: >> >> >> On 07/03/16 06:59, Shawn Lin wrote: >>> >>> We should return -EINVAL if cmd is not MMC_IOC_CMD or MMC_IOC_MULTI_CMD, >>> otherwise blkdev_roset will return -EPERM. >>> >>> Android-adb calls make_block_device_writable with ioctl(BLKROSET), which >>> will return error, make remount failed: >>> remount of /system failed; >>> couldn't make block device writable: Operation not permitted >> >> >> I think you should elaborate here why the behaviour between -EINVAL and >> -EPERM is different as they are both errors. In other words, add your >> comment about how the ADB code is checking for a supported command. > > > yep. So if need to send v2 after comment from Ulf, I will add more into > commit-msg. > > >> >>> openat(AT_FDCWD, "/dev/block/platform/ff420000.dwmmc/by-name/system", >>> O_RDONLY) = 3 >>> ioctl(3, BLKROSET, 0) = -1 EPERM (Operation not permitted) >>> >>> Fixes: a5f5774c55a2 ("mmc: block: Add new ioctl to send multi commands") >>> Cc: stable@vger.kernel.org >>> Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> >>> --- >>> >>> drivers/mmc/card/block.c | 3 +++ >>> 1 file changed, 3 insertions(+) >>> >>> diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c >>> index 47bc87d..170f099 100644 >>> --- a/drivers/mmc/card/block.c >>> +++ b/drivers/mmc/card/block.c >>> @@ -688,6 +688,9 @@ cmd_err: >>> static int mmc_blk_ioctl(struct block_device *bdev, fmode_t mode, >>> unsigned int cmd, unsigned long arg) >>> { >>> + if (cmd != MMC_IOC_CMD && cmd != MMC_IOC_MULTI_CMD) >>> + return -EINVAL; >>> + >>> /* >>> * The caller must have CAP_SYS_RAWIO, and must be calling this >>> on the >>> * whole block device, not on a partition. This prevents >>> overspray >> >> >> The change is fine with me, but I agree with Seshagiri's comment that >> instead of the above, move the following test to the mmc_blk_ioctl_cmd >> and mmc_blk_ioctl_multi_cmd functions: >> >> if ((!capable(CAP_SYS_RAWIO)) || (bdev != bdev->bd_contains)) >> return -EPERM; >> > > right, and both are ok to me :). > Adding this check for mmc_blk_ioctl_cmd and mmc_blk_ioctl_multi_cmd > respectively may also looks like we produce two some code sections that do > the same thing. > > I think it depends on how Ulf want the solution to be? Let's wait for > Ulf' comment. > I believe I prefer Jon/Seshagiri suggestions for this. It makes the code a bit more readable. Please send a v2 addressing their comments. Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c index 47bc87d..170f099 100644 --- a/drivers/mmc/card/block.c +++ b/drivers/mmc/card/block.c @@ -688,6 +688,9 @@ cmd_err: static int mmc_blk_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg) { + if (cmd != MMC_IOC_CMD && cmd != MMC_IOC_MULTI_CMD) + return -EINVAL; + /* * The caller must have CAP_SYS_RAWIO, and must be calling this on the * whole block device, not on a partition. This prevents overspray
We should return -EINVAL if cmd is not MMC_IOC_CMD or MMC_IOC_MULTI_CMD, otherwise blkdev_roset will return -EPERM. Android-adb calls make_block_device_writable with ioctl(BLKROSET), which will return error, make remount failed: remount of /system failed; couldn't make block device writable: Operation not permitted openat(AT_FDCWD, "/dev/block/platform/ff420000.dwmmc/by-name/system", O_RDONLY) = 3 ioctl(3, BLKROSET, 0) = -1 EPERM (Operation not permitted) Fixes: a5f5774c55a2 ("mmc: block: Add new ioctl to send multi commands") Cc: stable@vger.kernel.org Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> --- drivers/mmc/card/block.c | 3 +++ 1 file changed, 3 insertions(+)