Replace the SYSCTL_USER_TO_KERN_UINT_CONV and SYSCTL_UINT_CONV_CUSTOM macros with functions with the same logic. This makes debugging easier and aligns with the functions preference described in coding-style.rst. Update the only user of this API: pipe.c. Signed-off-by: Joel Granados --- fs/pipe.c | 22 ++++++-- include/linux/sysctl.h | 63 +++------------------- kernel/sysctl.c | 140 +++++++++++++++++++++++++++++++++++++++++++------ 3 files changed, 148 insertions(+), 77 deletions(-) diff --git a/fs/pipe.c b/fs/pipe.c index 9e6a01475815986ea2511868f66f4a8763978578..22647f50b286d3bca024ee4c6de51b100ddc5402 100644 --- a/fs/pipe.c +++ b/fs/pipe.c @@ -1481,10 +1481,24 @@ static struct file_system_type pipe_fs_type = { }; #ifdef CONFIG_SYSCTL -static SYSCTL_USER_TO_KERN_UINT_CONV(_pipe_maxsz, round_pipe_size) -static SYSCTL_UINT_CONV_CUSTOM(_pipe_maxsz, - sysctl_user_to_kern_uint_conv_pipe_maxsz, - sysctl_kern_to_user_uint_conv, true) + +static ulong round_pipe_size_ul(ulong size) +{ + return round_pipe_size(size); +} + +static int u2k_pipe_maxsz(const ulong *u_ptr, uint *k_ptr) +{ + return proc_uint_u2k_conv_uop(u_ptr, k_ptr, round_pipe_size_ul); +} + +static int do_proc_uint_conv_pipe_maxsz(ulong *u_ptr, uint *k_ptr, + int dir, const struct ctl_table *table) +{ + return proc_uint_conv(u_ptr, k_ptr, dir, table, true, + u2k_pipe_maxsz, + proc_uint_k2u_conv); +} static int proc_dopipe_max_size(const struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos) diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h index 0a64212a0ceb8454ae343831739831a092b6e693..d712992789f0f2f3fe4cec10fb14907b7fd61a7e 100644 --- a/include/linux/sysctl.h +++ b/include/linux/sysctl.h @@ -135,45 +135,6 @@ int do_proc_int_conv##name(bool *negp, unsigned long *u_ptr, int *k_ptr,\ return user_to_kern(negp, u_ptr, k_ptr); \ return 0; \ } - -#define SYSCTL_USER_TO_KERN_UINT_CONV(name, u_ptr_op) \ -int sysctl_user_to_kern_uint_conv##name(const unsigned long *u_ptr,\ - unsigned int *k_ptr) \ -{ \ - unsigned long u = u_ptr_op(*u_ptr); \ - if (u > UINT_MAX) \ - return -EINVAL; \ - WRITE_ONCE(*k_ptr, u); \ - return 0; \ -} - -#define SYSCTL_UINT_CONV_CUSTOM(name, user_to_kern, kern_to_user, \ - k_ptr_range_check) \ -int do_proc_uint_conv##name(unsigned long *u_ptr, unsigned int *k_ptr, \ - int dir, const struct ctl_table *tbl) \ -{ \ - if (SYSCTL_KERN_TO_USER(dir)) \ - return kern_to_user(u_ptr, k_ptr); \ - \ - if (k_ptr_range_check) { \ - unsigned int tmp_k; \ - int ret; \ - if (!tbl) \ - return -EINVAL; \ - ret = user_to_kern(u_ptr, &tmp_k); \ - if (ret) \ - return ret; \ - if ((tbl->extra1 && \ - *(unsigned int *)tbl->extra1 > tmp_k) || \ - (tbl->extra2 && \ - *(unsigned int *)tbl->extra2 < tmp_k)) \ - return -ERANGE; \ - WRITE_ONCE(*k_ptr, tmp_k); \ - } else \ - return user_to_kern(u_ptr, k_ptr); \ - return 0; \ -} - #else // CONFIG_PROC_SYSCTL #define SYSCTL_USER_TO_KERN_INT_CONV(name, u_ptr_op) \ int sysctl_user_to_kern_int_conv##name(const bool *negp, \ @@ -199,24 +160,8 @@ int do_proc_int_conv##name(bool *negp, unsigned long *u_ptr, int *k_ptr,\ return -ENOSYS; \ } -#define SYSCTL_USER_TO_KERN_UINT_CONV(name, u_ptr_op) \ -int sysctl_user_to_kern_uint_conv##name(const unsigned long *u_ptr,\ - unsigned int *k_ptr) \ -{ \ - return -ENOSYS; \ -} - -#define SYSCTL_UINT_CONV_CUSTOM(name, user_to_kern, kern_to_user, \ - k_ptr_range_check) \ -int do_proc_uint_conv##name(unsigned long *u_ptr, unsigned int *k_ptr, \ - int dir, const struct ctl_table *tbl) \ -{ \ - return -ENOSYS; \ -} - #endif // CONFIG_PROC_SYSCTL - extern const unsigned long sysctl_long_vals[]; typedef int proc_handler(const struct ctl_table *ctl, int write, void *buffer, @@ -239,6 +184,13 @@ int proc_douintvec_conv(const struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos, int (*conv)(unsigned long *lvalp, unsigned int *valp, int write, const struct ctl_table *table)); +int proc_uint_k2u_conv(ulong *u_ptr, const uint *k_ptr); +int proc_uint_u2k_conv_uop(const ulong *u_ptr, uint *k_ptr, + ulong (*u_ptr_op)(const ulong)); +int proc_uint_conv(ulong *u_ptr, uint *k_ptr, int dir, + const struct ctl_table *tbl, bool k_ptr_range_check, + int (*user_to_kern)(const ulong *u_ptr, uint *k_ptr), + int (*kern_to_user)(ulong *u_ptr, const uint *k_ptr)); int proc_dou8vec_minmax(const struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos); @@ -249,7 +201,6 @@ int proc_doulongvec_minmax_conv(const struct ctl_table *table, int dir, int proc_do_large_bitmap(const struct ctl_table *, int, void *, size_t *, loff_t *); int proc_do_static_key(const struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos); -int sysctl_kern_to_user_uint_conv(unsigned long *u_ptr, const unsigned int *k_ptr); /* * Register a set of sysctl names by calling register_sysctl diff --git a/kernel/sysctl.c b/kernel/sysctl.c index e82716b7c13840cadc3b19a7c9d05b167abebcf6..5901196a52f98cdd5aba4f50899a58d9bd9d10f9 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -354,6 +354,110 @@ static void proc_put_char(void **buf, size_t *size, char c) } } +/** + * proc_uint_u2k_conv_uop - Assign user value to a kernel pointer + * + * @u_ptr: pointer to user space variable + * @k_ptr: pointer to kernel variable + * @u_ptr_op: execute this function before assigning to k_ptr + * + * Uses WRITE_ONCE to assign value to k_ptr. Executes u_ptr_op if + * not NULL. Check that the values are less than UINT_MAX to avoid + * having to support wrap around from userspace. + * + * returns 0 on success. + */ +int proc_uint_u2k_conv_uop(const ulong *u_ptr, uint *k_ptr, + ulong (*u_ptr_op)(const ulong)) +{ + ulong u = u_ptr_op ? u_ptr_op(*u_ptr) : *u_ptr; + + if (u > UINT_MAX) + return -EINVAL; + WRITE_ONCE(*k_ptr, u); + return 0; +} + +/** + * proc_uint_k2u_conv - Assign kernel value to a user space pointer + * + * @u_ptr: pointer to user space variable + * @k_ptr: pointer to kernel variable + * + * Uses READ_ONCE to assign value to u_ptr. + * + * returns 0 on success. + */ +int proc_uint_k2u_conv(ulong *u_ptr, const uint *k_ptr) +{ + uint val = READ_ONCE(*k_ptr); + *u_ptr = (ulong)val; + return 0; +} + +/** + * proc_uint_conv - Change user or kernel pointer based on direction + * + * @u_ptr: pointer to user variable + * @k_ptr: pointer to kernel variable + * @dir: %TRUE if this is a write to the sysctl file + * @tbl: the sysctl table + * @k_ptr_range_check: Check range for k_ptr when %TRUE + * @user_to_kern: Callback used to assign value from user to kernel var + * @kern_to_user: Callback used to assign value from kernel to user var + * + * When direction is kernel to user, then the u_ptr is modified. + * When direction is user to kernel, then the k_ptr is modified. + * + * Returns 0 on success + */ +int proc_uint_conv(ulong *u_ptr, uint *k_ptr, int dir, + const struct ctl_table *tbl, bool k_ptr_range_check, + int (*user_to_kern)(const ulong *u_ptr, uint *k_ptr), + int (*kern_to_user)(ulong *u_ptr, const uint *k_ptr)) +{ + if (SYSCTL_KERN_TO_USER(dir)) + return kern_to_user(u_ptr, k_ptr); + + if (k_ptr_range_check) { + uint tmp_k; + int ret; + + if (!tbl) + return -EINVAL; + ret = user_to_kern(u_ptr, &tmp_k); + if (ret) + return ret; + if ((tbl->extra1 && + *(uint *)tbl->extra1 > tmp_k) || + (tbl->extra2 && + *(uint *)tbl->extra2 < tmp_k)) + return -ERANGE; + WRITE_ONCE(*k_ptr, tmp_k); + } else + return user_to_kern(u_ptr, k_ptr); + return 0; +} + +static int proc_uint_u2k_conv(const ulong *u_ptr, uint *k_ptr) +{ + return proc_uint_u2k_conv_uop(u_ptr, k_ptr, NULL); +} + +static int do_proc_uint_conv(ulong *u_ptr, uint *k_ptr, int dir, + const struct ctl_table *tbl) +{ + return proc_uint_conv(u_ptr, k_ptr, dir, tbl, false, + proc_uint_u2k_conv, proc_uint_k2u_conv); +} + +static int do_proc_uint_conv_minmax(ulong *u_ptr, uint *k_ptr, int dir, + const struct ctl_table *tbl) +{ + return proc_uint_conv(u_ptr, k_ptr, dir, tbl, true, + proc_uint_u2k_conv, proc_uint_k2u_conv); +} + static SYSCTL_USER_TO_KERN_INT_CONV(, SYSCTL_CONV_IDENTITY) static SYSCTL_KERN_TO_USER_INT_CONV(, SYSCTL_CONV_IDENTITY) @@ -362,22 +466,6 @@ static SYSCTL_INT_CONV_CUSTOM(, sysctl_user_to_kern_int_conv, static SYSCTL_INT_CONV_CUSTOM(_minmax, sysctl_user_to_kern_int_conv, sysctl_kern_to_user_int_conv, true) - -static SYSCTL_USER_TO_KERN_UINT_CONV(, SYSCTL_CONV_IDENTITY) - -int sysctl_kern_to_user_uint_conv(unsigned long *u_ptr, - const unsigned int *k_ptr) -{ - unsigned int val = READ_ONCE(*k_ptr); - *u_ptr = (unsigned long)val; - return 0; -} - -static SYSCTL_UINT_CONV_CUSTOM(, sysctl_user_to_kern_uint_conv, - sysctl_kern_to_user_uint_conv, false) -static SYSCTL_UINT_CONV_CUSTOM(_minmax, sysctl_user_to_kern_uint_conv, - sysctl_kern_to_user_uint_conv, true) - static const char proc_wspace_sep[] = { ' ', '\t', '\n' }; static int do_proc_dointvec(const struct ctl_table *table, int dir, @@ -576,7 +664,6 @@ int proc_douintvec_conv(const struct ctl_table *table, int dir, void *buffer, return do_proc_douintvec(table, dir, buffer, lenp, ppos, conv); } - /** * proc_dobool - read/write a bool * @table: the sysctl table @@ -1063,6 +1150,25 @@ int proc_douintvec_conv(const struct ctl_table *table, int write, void *buffer, return -ENOSYS; } +int proc_uint_k2u_conv(ulong *u_ptr, const uint *k_ptr) +{ + return -ENOSYS; +} + +int proc_uint_u2k_conv_uop(const ulong *u_ptr, uint *k_ptr, + ulong (*u_ptr_op)(const ulong)) +{ + return -ENOSYS; +} + +int proc_uint_conv(ulong *u_ptr, uint *k_ptr, int dir, + const struct ctl_table *tbl, bool k_ptr_range_check, + int (*user_to_kern)(const ulong *u_ptr, uint *k_ptr), + int (*kern_to_user)(ulong *u_ptr, const uint *k_ptr)) +{ + return -ENOSYS; +} + int proc_dou8vec_minmax(const struct ctl_table *table, int dir, void *buffer, size_t *lenp, loff_t *ppos) { -- 2.50.1