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charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20261102-work-procfs-drivers-v1-13-a994bd4d3b1a@kernel.org> References: <20261102-work-procfs-drivers-v1-0-a994bd4d3b1a@kernel.org> In-Reply-To: <20261102-work-procfs-drivers-v1-0-a994bd4d3b1a@kernel.org> To: linux-fsdevel@vger.kernel.org Cc: Linus Torvalds , Jann Horn , Josef Bacik , Chris Mason , Jeff Layton , NeilBrown , Eric Dumazet , Thomas Gleixner , Al Viro , Jonathan Corbet , Christoph Hellwig , Greg Kroah-Hartman , Joel Granados , Kees Cook , Jan Kara , Jan Kara , linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-acpi@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-s390@vger.kernel.org, linux-scsi@vger.kernel.org, linux-um@lists.infradead.org, linux-wireless@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org, ntfs3@lists.linux.dev, platform-driver-x86@vger.kernel.org, coreteam@netfilter.org, kexec@lists.infradead.org, linux-pci@vger.kernel.org, linux-sound@vger.kernel.org, netfilter-devel@vger.kernel.org, dri-devel@lists.freedesktop.org, ibm-acpi-devel@lists.sourceforge.net, jfs-discussion@lists.sourceforge.net, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-cifs@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-mm@kvack.org, linux-sh@vger.kernel.org, linux-usb@vger.kernel.org, samba-technical@lists.samba.org, sparclinux@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-doc@vger.kernel.org, linux-serial@vger.kernel.org, linux-atm-general@lists.sourceforge.net, Takashi Iwai , linux-input@vger.kernel.org, linux-raid@vger.kernel.org, linux-ext4@vger.kernel.org, linux-modules@vger.kernel.org, linux-debuggers@vger.kernel.org, "Christian Brauner (Amutable)" , Chuck Lever X-Mailer: b4 0.17-dev X-Developer-Signature: v=1; a=openpgp-sha256; l=2854; i=brauner@kernel.org; h=from:subject:message-id; bh=JvNn9BiAujB73ykVLFuVWE/fT8/HBZYijRncXc4d9K0=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMWS9WG7QvpbRg3P21cqJ8ja/jDbycj3eZxhYsFFhyvyCU 9Jr5m792VHKwiDGxSArpsji0G4SLrecp2KzUaYGzBxWJpAhDFycAjCRezmMDGdFpl5cZz2xV6VK 67ro+4sRqiHvTXWiV/ytnnPXy7w9S4mR4UuS786S182/LwXZn3kWWap7OH/GKcMfobE/OF7euZe 9ihEA X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 Implement ->proc_write_buf() for allow_dio and def_reserved_size so procfs copies in what is written before it pins the entry, and parse the number from that copy. kstrtoul_from_user() looked at the first 66 bytes of whatever was written. Now the whole write is parsed, and anything larger than PAGE_SIZE - 1 bytes fails with -EINVAL from procfs before the capability check. Signed-off-by: Christian Brauner (Amutable) --- drivers/scsi/sg.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index c7386fbe5580..87569e302f26 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -2287,18 +2287,18 @@ sg_get_dev(int dev) #ifdef CONFIG_SCSI_PROC_FS static int sg_proc_seq_show_int(struct seq_file *s, void *v); -static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer, +static ssize_t sg_proc_write_adio(struct file *filp, char *buffer, size_t count, loff_t *off); static const struct proc_ops adio_proc_ops = { .proc_show = sg_proc_seq_show_int, - .proc_write = sg_proc_write_adio, + .proc_write_buf = sg_proc_write_adio, }; static ssize_t sg_proc_write_dressz(struct file *filp, - const char __user *buffer, size_t count, loff_t *off); + char *buffer, size_t count, loff_t *off); static const struct proc_ops dressz_proc_ops = { .proc_show = sg_proc_seq_show_int, - .proc_write = sg_proc_write_dressz, + .proc_write_buf = sg_proc_write_dressz, }; static int sg_proc_seq_show_version(struct seq_file *s, void *v); @@ -2359,7 +2359,7 @@ static int sg_proc_seq_show_int(struct seq_file *s, void *v) } static ssize_t -sg_proc_write_adio(struct file *filp, const char __user *buffer, +sg_proc_write_adio(struct file *filp, char *buffer, size_t count, loff_t *off) { int err; @@ -2367,7 +2367,7 @@ sg_proc_write_adio(struct file *filp, const char __user *buffer, if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) return -EACCES; - err = kstrtoul_from_user(buffer, count, 0, &num); + err = kstrtoul(buffer, 0, &num); if (err) return err; sg_allow_dio = num ? 1 : 0; @@ -2375,7 +2375,7 @@ sg_proc_write_adio(struct file *filp, const char __user *buffer, } static ssize_t -sg_proc_write_dressz(struct file *filp, const char __user *buffer, +sg_proc_write_dressz(struct file *filp, char *buffer, size_t count, loff_t *off) { int err; @@ -2384,7 +2384,7 @@ sg_proc_write_dressz(struct file *filp, const char __user *buffer, if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) return -EACCES; - err = kstrtoul_from_user(buffer, count, 0, &k); + err = kstrtoul(buffer, 0, &k); if (err) return err; if (k <= 1048576) { /* limit "big buff" to 1 MB */ -- 2.53.0