Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
sysctl: Add optional range checking to SYSCTL_UINT_CONV_CUSTOM
Add k_ptr_range_check parameter to SYSCTL_UINT_CONV_CUSTOM macro to
enable range validation using table->extra1/extra2. Replace
do_proc_douintvec_minmax_conv with do_proc_uint_conv_minmax generated
by the updated macro.
Signed-off-by: Joel Granados <joel.granados@kernel.org>
+32
-37
+32
-37
kernel/sysctl.c
+32
-37
kernel/sysctl.c
···
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sysctl_user_to_kern_int_conv_ms,
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sysctl_kern_to_user_int_conv_ms, true)
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#define SYSCTL_UINT_CONV_CUSTOM(name, user_to_kern, kern_to_user) \
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int do_proc_uint_conv##name(unsigned long *u_ptr, unsigned int *k_ptr, \
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int dir, const struct ctl_table *tbl) \
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{ \
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if (SYSCTL_USER_TO_KERN(dir)) \
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return user_to_kern(u_ptr, k_ptr); \
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return kern_to_user(u_ptr, k_ptr); \
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}
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static int sysctl_user_to_kern_uint_conv(const unsigned long *u_ptr,
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unsigned int *k_ptr)
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{
···
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return 0;
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}
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+
#define SYSCTL_UINT_CONV_CUSTOM(name, user_to_kern, kern_to_user, \
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k_ptr_range_check) \
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int do_proc_uint_conv##name(unsigned long *u_ptr, unsigned int *k_ptr, \
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int dir, const struct ctl_table *tbl) \
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{ \
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if (SYSCTL_KERN_TO_USER(dir)) \
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return kern_to_user(u_ptr, k_ptr); \
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\
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if (k_ptr_range_check) { \
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unsigned int tmp_k; \
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int ret; \
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if (!tbl) \
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return -EINVAL; \
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ret = user_to_kern(u_ptr, &tmp_k); \
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if (ret) \
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return ret; \
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if ((tbl->extra1 && \
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*(unsigned int *)tbl->extra1 > tmp_k) || \
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(tbl->extra2 && \
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*(unsigned int *)tbl->extra2 < tmp_k)) \
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return -ERANGE; \
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WRITE_ONCE(*k_ptr, tmp_k); \
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} else \
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return user_to_kern(u_ptr, k_ptr); \
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return 0; \
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}
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+
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static SYSCTL_UINT_CONV_CUSTOM(, sysctl_user_to_kern_uint_conv,
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-
sysctl_kern_to_user_uint_conv)
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sysctl_kern_to_user_uint_conv, false)
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static SYSCTL_UINT_CONV_CUSTOM(_minmax, sysctl_user_to_kern_uint_conv,
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sysctl_kern_to_user_uint_conv, true)
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static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
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···
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do_proc_int_conv_minmax);
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}
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static int do_proc_douintvec_minmax_conv(unsigned long *u_ptr,
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unsigned int *k_ptr, int dir,
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const struct ctl_table *table)
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{
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int ret;
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unsigned int tmp, *min, *max;
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/* When writing to the kernel use a temp local uint for bounds-checking */
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unsigned int *up = SYSCTL_USER_TO_KERN(dir) ? &tmp : k_ptr;
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-
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ret = do_proc_uint_conv(u_ptr, up, dir, table);
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if (ret)
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return ret;
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if (SYSCTL_USER_TO_KERN(dir)) {
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min = (unsigned int *) table->extra1;
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max = (unsigned int *) table->extra2;
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if ((min && *min > tmp) || (max && *max < tmp))
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return -ERANGE;
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WRITE_ONCE(*k_ptr, tmp);
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}
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return 0;
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}
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/**
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* proc_douintvec_minmax - read a vector of unsigned ints with min/max values
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* @table: the sysctl table
···
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void *buffer, size_t *lenp, loff_t *ppos)
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{
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return do_proc_douintvec(table, dir, buffer, lenp, ppos,
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-
do_proc_douintvec_minmax_conv);
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+
do_proc_uint_conv_minmax);
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}
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/**
···
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val = READ_ONCE(*data);
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res = do_proc_douintvec(&tmp, dir, buffer, lenp, ppos,
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do_proc_douintvec_minmax_conv);
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+
do_proc_uint_conv_minmax);
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if (res)
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return res;
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if (SYSCTL_USER_TO_KERN(dir))