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* MFH: r306306julian2016-12-021-2/+2
| | | | | | Give the user a clue as to which process hit maxfiles. Sponsored by: Panzura
* MFC r298819:bdrewery2016-06-271-3/+3
| | | | sys/kern: spelling fixes in comments.
* MFC 287442,287537,288944:jhb2016-02-101-5/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix corruption of coredumps due to procstat notes changing size during coredump generation. The changes in r287442 required some reworking since the 'fo_fill_kinfo' file op does not exist in stable/10. 287442: Detect badly behaved coredump note helpers Coredump notes depend on being able to invoke dump routines twice; once in a dry-run mode to get the size of the note, and another to actually emit the note to the corefile. When a note helper emits a different length section the second time around than the length it requested the first time, the kernel produces a corrupt coredump. NT_PROCSTAT_FILES output length, when packing kinfo structs, is tied to the length of filenames corresponding to vnodes in the process' fd table via vn_fullpath. As vnodes may move around during dump, this is racy. So: - Detect badly behaved notes in putnote() and pad underfilled notes. - Add a fail point, debug.fail_point.fill_kinfo_vnode__random_path to exercise the NT_PROCSTAT_FILES corruption. It simply picks random lengths to expand or truncate paths to in fo_fill_kinfo_vnode(). - Add a sysctl, kern.coredump_pack_fileinfo, to allow users to disable kinfo packing for PROCSTAT_FILES notes. This should avoid both FILES note corruption and truncation, even if filenames change, at the cost of about 1 kiB in padding bloat per open fd. Document the new sysctl in core.5. - Fix note_procstat_files to self-limit in the 2nd pass. Since sometimes this will result in a short write, pad up to our advertised size. This addresses note corruption, at the risk of sometimes truncating the last several fd info entries. - Fix NT_PROCSTAT_FILES consumers libutil and libprocstat to grok the zero padding. 287537: Follow-up to r287442: Move sysctl to compiled-once file Avoid duplicate sysctl nodes. 288944: Fix core corruption caused by race in note_procstat_vmmap This fix is spiritually similar to r287442 and was discovered thanks to the KASSERT added in that revision. NT_PROCSTAT_VMMAP output length, when packing kinfo structs, is tied to the length of filenames corresponding to vnodes in the process' vm map via vn_fullpath. As vnodes may move during coredump, this is racy. We do not remove the race, only prevent it from causing coredump corruption. - Add a sysctl, kern.coredump_pack_vmmapinfo, to allow users to disable kinfo packing for PROCSTAT_VMMAP notes. This avoids VMMAP corruption and truncation, even if names change, at the cost of up to PATH_MAX bytes per mapped object. The new sysctl is documented in core.5. - Fix note_procstat_vmmap to self-limit in the second pass. This addresses corruption, at the cost of sometimes producing a truncated result. - Fix PROCSTAT_VMMAP consumers libutil (and libprocstat, via copy-paste) to grok the new zero padding. Approved by: re (gjb)
* MFC r285134 (by mjg):kib2015-07-281-28/+24
| | | | | | | fd: de-k&r-ify functions + some whitespace fixes MFC r285269: Handle copyout for the fcntl(F_OGETLK) using oflock structure.
* MFC r282213:trasz2015-06-211-15/+21
| | | | | | | | | | | | | | | | | | Add kern.racct.enable tunable and RACCT_DISABLED config option. The point of this is to be able to add RACCT (with RACCT_DISABLED) to GENERIC, to avoid having to rebuild the kernel to use rctl(8). MFC r282901: Build GENERIC with RACCT/RCTL support by default. Note that it still needs to be enabled by adding "kern.racct.enable=1" to /boot/loader.conf. Note those two are MFC-ed together, because the latter one changes the name of RACCT_DISABLED option to RACCT_DEFAULT_TO_DISABLED. Should have committed the renaming separately... Relnotes: yes Sponsored by: The FreeBSD Foundation
* Merge r263233 from HEAD to stable/10:rwatson2015-03-191-1/+1
| | | | | | | | | Update kernel inclusions of capability.h to use capsicum.h instead; some further refinement is required as some device drivers intended to be portable over FreeBSD versions rely on __FreeBSD_version to decide whether to include capability.h. Sponsored by: Google, Inc.
* MFC r272566:kib2015-03-121-1/+1
| | | | Convert -1 from sbuf_bcat() to ENOMEM.
* MFC r263710, r273377, r273378, r273423 and r273455:hselasky2014-10-271-1/+1
| | | | | | | - De-vnet hash sizes and hash masks. - Fix multiple issues related to arguments passed to SYSCTL macros. Sponsored by: Mellanox Technologies
* MFC r269023,r272503,r272505,r272523,r272567,r272569,r272574mjg2014-10-141-9/+62
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Prepare fget_unlocked for reading fd table only once. Some capsicum functions accept fdp + fd and lookup fde based on that. Add variants which accept fde. =============================== Add sequence counters with memory barriers. Current implementation is somewhat simplistic and hackish, will be improved later after possible memory barrier overhaul. =============================== Plug capability races. fp and appropriate capability lookups were not atomic, which could result in improper capabilities being checked. This could result either in protection bypass or in a spurious ENOTCAPABLE. Make fp + capability check atomic with the help of sequence counters. =============================== Put and #ifdef _KERNEL around the #include for opt_capsicum.h to hopefully allow the build to finish after r272505. =============================== filedesc: fix up breakage introduced in 272505 Include sequence counter supports incoditionally [1]. This fixes reprted build problems with e.g. nvidia driver due to missing opt_capsicum.h. Replace fishy looking sizeof with offsetof. Make fde_seq the last member in order to simplify calculations. =============================== Keep struct filedescent comments within 80-char limit. =============================== seq_t needs to be visible to userspace
* MFC r272132:kib2014-09-281-15/+20
| | | | | | Fix fcntl(2) compat32 after r270691. Approved by: re (glebius)
* MFC r270993:mjg2014-09-261-16/+13
| | | | | | | | | | Fix up proc_realparent to always return correct process. Prior to the change it would always return initproc for non-traced processes. This fixes a regression in inferior(). Approved by: re (marius)
* MFC r268505, r268507:mjg2014-08-171-17/+31
| | | | | | | | | | | | | | | | Avoid relocking filedesc lock when closing fds during fdp destruction. Don't call bzero nor fdunused from fdfree for such cases. It would do unnecessary work and complain that the lock is not taken. ======= Don't zero fd_nfiles during fdp destruction. Code trying to take a look has to check fd_refcnt and it is 0 by that time. This is a follow up to r268505, without this the code would leak memory for tables bigger than the default.
* MFC r268001:mjg2014-07-061-1/+2
| | | | | | | Make fdunshare accept only td parameter. Proc had to match the thread anyway and 2 parameters were inconsistent with the rest.
* MFC r268000:mjg2014-07-061-5/+5
| | | | | | | | | | | | Make sure to always clear p_fd for process getting rid of its filetable. Filetable can be shared with other processes. Previous code failed to clear the pointer for all but the last process getting rid of the table. This is mostly cosmetics. Get rid of 'This should happen earlier' comment. Clearing the pointer in this place is fine as consumers can reliably check for files availability by inspecting fd_refcnt and vnodes availabity by NULL-checking them.
* MFC r267760:mjg2014-07-061-18/+2
| | | | | | | | | | | | Tidy up fd-related functions called by do_execve o assert in each one that fdp is not shared o remove unnecessary NULL checks - all userspace processes have fdtables and kernel processes cannot execve o remove comments about the danger of fd_ofiles getting reallocated - fdtable is not shared and fd_ofiles could be only reallocated if new fd was about to be added, but if that was possible the code would already be buggy as setugidsafety work could be undone
* MFC r267755:mjg2014-07-061-9/+6
| | | | | | | | | | Don't take filedesc lock in fdunshare(). We can read refcnt safely and only care if it is equal to 1. If it could suddenly change from 1 to something bigger the code would be buggy even in the previous form and transitions from > 1 to 1 are equally racy and harmless (we copy even though there is no need).
* MFC r267710:mjg2014-07-061-6/+6
| | | | | | | | | | fd: replace fd_nfiles with fd_lastfile where appropriate fd_lastfile is guaranteed to be the biggest open fd, so when the intent is to iterate over active fds or lookup one, there is no point in looking beyond that limit. Few places are left unpatched for now.
* MFC r267708:mjg2014-07-061-2/+0
| | | | | | | do_dup: plug redundant adjustment of fd_lastfile By that time it was already set by fdalloc, or was there in the first place if fd is replaced.
* MFC r265247:mjg2014-07-061-2/+2
| | | | | | Request a non-exiting process in sysctl_kern_proc_{o,}filedesc This fixes a race with exit1 freeing p_textvp.
* MFC r263530:mjg2014-03-311-5/+7
| | | | | | | Mark the following sysctls as MPSAFE: kern.file kern.proc.filedesc kern.proc.ofiledesc
* MFC r263460:mjg2014-03-311-2/+2
| | | | | | Take filedesc lock only for reading when allocating new fdtable. Code populating the table does this already.
* MFC r262006,r262328:bdrewery2014-03-021-11/+21
| | | | | | | | | | r262006: Fix M_FILEDESC leak in fdgrowtable() introduced in r244510. fdgrowtable() now only reallocates fd_map when necessary. r262328: Style. Approved by: bapt (mentor, implicit)
* MFC r262005:bdrewery2014-03-021-1/+0
| | | | | | Remove redundant memcpy of fd_ofiles in fdgrowtable() Approved by: bapt (mentor, implicit)
* MFC r262309:mjg2014-02-241-2/+2
| | | | | | | | Fix a race between kern_proc_{o,}filedesc_out and fdescfree leading to use-after-free. fdescfree proceeds to free file pointers once fd_refcnt reaches 0, but kern_proc_{o,}filedesc_out only checked for hold count.
* MFC r260233:mjg2014-02-201-0/+1
| | | | Plug a memory leak in dup2 when both old and new fd have ioctl caps.
* MFC r260232:mjg2014-01-071-6/+1
| | | | | | | | Don't check for fd limits in fdgrowtable_exp. Callers do that already and additional check races with process decreasing limits and can result in not growing the table at all, which is currently not handled.
* When growing the file descriptor table, new larger memory chunk iskib2013-10-091-2/+21
| | | | | | | | | | | | | | | allocated, but the old table is kept around to handle the case of threads still performing unlocked accesses to it. Grow the table exponentially instead of increasing its size by sizeof(long) * 8 chunks when overflowing. This mode significantly reduces the total memory use for the processes consuming large numbers of the file descriptors which open them one by one. Reported and tested by: pho Sponsored by: The FreeBSD Foundation MFC after: 1 week Approved by: re (marius)
* Reduce code duplication, introduce the getmaxfd() helper to calculatekib2013-10-091-9/+16
| | | | | | | | | the max filedescriptor index. Tested by: pho Sponsored by: The FreeBSD Foundation MFC after: 1 week Approved by: re (marius)
* it must be the last member, not might...jmg2013-09-261-1/+1
| | | | | Reviewed by: attilio Approved by: re (delphij, gjb)
* Avoid memory accesses reordering which can result in fget_unlocked()attilio2013-09-251-2/+14
| | | | | | | | | | seeing a stale fd_ofiles table once fd_nfiles is already updated, resulting in OOB accesses. Approved by: re (kib) Sponsored by: EMC / Isilon storage division Reported and tested by: pho Reviewed by: benno
* Handle cases where capability rights are not provided.pjd2013-09-051-13/+20
| | | | Reported by: kib
* Change the cap_rights_t type from uint64_t to a structure that we can extendpjd2013-09-051-59/+78
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | in the future in a backward compatible (API and ABI) way. The cap_rights_t represents capability rights. We used to use one bit to represent one right, but we are running out of spare bits. Currently the new structure provides place for 114 rights (so 50 more than the previous cap_rights_t), but it is possible to grow the structure to hold at least 285 rights, although we can make it even larger if 285 rights won't be enough. The structure definition looks like this: struct cap_rights { uint64_t cr_rights[CAP_RIGHTS_VERSION + 2]; }; The initial CAP_RIGHTS_VERSION is 0. The top two bits in the first element of the cr_rights[] array contain total number of elements in the array - 2. This means if those two bits are equal to 0, we have 2 array elements. The top two bits in all remaining array elements should be 0. The next five bits in all array elements contain array index. Only one bit is used and bit position in this five-bits range defines array index. This means there can be at most five array elements in the future. To define new right the CAPRIGHT() macro must be used. The macro takes two arguments - an array index and a bit to set, eg. #define CAP_PDKILL CAPRIGHT(1, 0x0000000000000800ULL) We still support aliases that combine few rights, but the rights have to belong to the same array element, eg: #define CAP_LOOKUP CAPRIGHT(0, 0x0000000000000400ULL) #define CAP_FCHMOD CAPRIGHT(0, 0x0000000000002000ULL) #define CAP_FCHMODAT (CAP_FCHMOD | CAP_LOOKUP) There is new API to manage the new cap_rights_t structure: cap_rights_t *cap_rights_init(cap_rights_t *rights, ...); void cap_rights_set(cap_rights_t *rights, ...); void cap_rights_clear(cap_rights_t *rights, ...); bool cap_rights_is_set(const cap_rights_t *rights, ...); bool cap_rights_is_valid(const cap_rights_t *rights); void cap_rights_merge(cap_rights_t *dst, const cap_rights_t *src); void cap_rights_remove(cap_rights_t *dst, const cap_rights_t *src); bool cap_rights_contains(const cap_rights_t *big, const cap_rights_t *little); Capability rights to the cap_rights_init(), cap_rights_set(), cap_rights_clear() and cap_rights_is_set() functions are provided by separating them with commas, eg: cap_rights_t rights; cap_rights_init(&rights, CAP_READ, CAP_WRITE, CAP_FSTAT); There is no need to terminate the list of rights, as those functions are actually macros that take care of the termination, eg: #define cap_rights_set(rights, ...) \ __cap_rights_set((rights), __VA_ARGS__, 0ULL) void __cap_rights_set(cap_rights_t *rights, ...); Thanks to using one bit as an array index we can assert in those functions that there are no two rights belonging to different array elements provided together. For example this is illegal and will be detected, because CAP_LOOKUP belongs to element 0 and CAP_PDKILL to element 1: cap_rights_init(&rights, CAP_LOOKUP | CAP_PDKILL); Providing several rights that belongs to the same array's element this way is correct, but is not advised. It should only be used for aliases definition. This commit also breaks compatibility with some existing Capsicum system calls, but I see no other way to do that. This should be fine as Capsicum is still experimental and this change is not going to 9.x. Sponsored by: The FreeBSD Foundation
* Make sendfile() a method in the struct fileops. Currently onlyglebius2013-08-151-0/+19
| | | | | | | | vnode backed file descriptors have this method implemented. Reviewed by: kib Sponsored by: Nginx, Inc. Sponsored by: Netflix
* Plug up the lock lock leakage when exporting to a short buffer.trociny2013-07-011-0/+2
| | | | | | Reported by: Alexander Leidinger Submitted by: mjg MFC after: 1 week
* Remove duplicate NULL check in kern_proc_filedesc_out.mjg2013-06-281-2/+1
| | | | | | No functional changes. MFC after: 1 week
* Rework r252313:trociny2013-06-281-29/+40
| | | | | | | | | | | | | | | The filedesc lock may not be dropped unconditionally before exporting fd to sbuf: fd might go away during execution. While it is ok for DTYPE_VNODE and DTYPE_FIFO because the export is from a vrefed vnode here, for other types it is unsafe. Instead, drop the lock in export_fd_to_sb(), after preparing data in memory and before writing to sbuf. Spotted by: mjg Suggested by: kib Review by: kib MFC after: 1 week
* To avoid LOR, always drop the filedesc lock before exporting fd to sbuf.trociny2013-06-271-4/+2
| | | | | Reviewed by: kib MFC after: 3 days
* Similar to 233760 and 236717, export some more useful info about thejhb2013-05-031-0/+31
| | | | | | | | | | | | | | | kernel-based POSIX semaphore descriptors to userland via procstat(1) and fstat(1): - Change sem file descriptors to track the pathname they are associated with and add a ksem_info() method to copy the path out to a caller-supplied buffer. - Use the fo_stat() method of shared memory objects and ksem_info() to export the path, mode, and value of a semaphore via struct kinfo_file. - Add a struct semstat to the libprocstat(3) interface along with a procstat_get_sem_info() to export the mode and value of a semaphore. - Teach fstat about semaphores and to display their path, mode, and value. MFC after: 2 weeks
* Re-factor the code to provide kern_proc_filedesc_out(), kern_proc_out(),trociny2013-04-141-40/+68
| | | | | | | | | | | and kern_proc_vmmap_out() functions to output process kinfo structures to sbuf, to make the code reusable. The functions are going to be used in the coredump routine to store procstat info in the core program header notes. Reviewed by: kib MFC after: 3 weeks
* Add fdallocn function and use it when passing fds over unix socket.mjg2013-04-141-0/+28
| | | | | | | This gets rid of "unp_externalize fdalloc failed" panic. Reviewed by: pjd MFC after: 1 week
* Use pget(9) to reduce code duplication.trociny2013-04-071-10/+4
| | | | MFC after: 1 week
* Use dedicated malloc type for filecaps-related data, so we can detect anypjd2013-03-031-2/+3
| | | | memory leaks easier.
* Plug memory leaks in file descriptors passing.pjd2013-03-031-1/+1
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* Merge Capsicum overhaul:pjd2013-03-021-332/+331
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Capability is no longer separate descriptor type. Now every descriptor has set of its own capability rights. - The cap_new(2) system call is left, but it is no longer documented and should not be used in new code. - The new syscall cap_rights_limit(2) should be used instead of cap_new(2), which limits capability rights of the given descriptor without creating a new one. - The cap_getrights(2) syscall is renamed to cap_rights_get(2). - If CAP_IOCTL capability right is present we can further reduce allowed ioctls list with the new cap_ioctls_limit(2) syscall. List of allowed ioctls can be retrived with cap_ioctls_get(2) syscall. - If CAP_FCNTL capability right is present we can further reduce fcntls that can be used with the new cap_fcntls_limit(2) syscall and retrive them with cap_fcntls_get(2). - To support ioctl and fcntl white-listing the filedesc structure was heavly modified. - The audit subsystem, kdump and procstat tools were updated to recognize new syscalls. - Capability rights were revised and eventhough I tried hard to provide backward API and ABI compatibility there are some incompatible changes that are described in detail below: CAP_CREATE old behaviour: - Allow for openat(2)+O_CREAT. - Allow for linkat(2). - Allow for symlinkat(2). CAP_CREATE new behaviour: - Allow for openat(2)+O_CREAT. Added CAP_LINKAT: - Allow for linkat(2). ABI: Reuses CAP_RMDIR bit. - Allow to be target for renameat(2). Added CAP_SYMLINKAT: - Allow for symlinkat(2). Removed CAP_DELETE. Old behaviour: - Allow for unlinkat(2) when removing non-directory object. - Allow to be source for renameat(2). Removed CAP_RMDIR. Old behaviour: - Allow for unlinkat(2) when removing directory. Added CAP_RENAMEAT: - Required for source directory for the renameat(2) syscall. Added CAP_UNLINKAT (effectively it replaces CAP_DELETE and CAP_RMDIR): - Allow for unlinkat(2) on any object. - Required if target of renameat(2) exists and will be removed by this call. Removed CAP_MAPEXEC. CAP_MMAP old behaviour: - Allow for mmap(2) with any combination of PROT_NONE, PROT_READ and PROT_WRITE. CAP_MMAP new behaviour: - Allow for mmap(2)+PROT_NONE. Added CAP_MMAP_R: - Allow for mmap(PROT_READ). Added CAP_MMAP_W: - Allow for mmap(PROT_WRITE). Added CAP_MMAP_X: - Allow for mmap(PROT_EXEC). Added CAP_MMAP_RW: - Allow for mmap(PROT_READ | PROT_WRITE). Added CAP_MMAP_RX: - Allow for mmap(PROT_READ | PROT_EXEC). Added CAP_MMAP_WX: - Allow for mmap(PROT_WRITE | PROT_EXEC). Added CAP_MMAP_RWX: - Allow for mmap(PROT_READ | PROT_WRITE | PROT_EXEC). Renamed CAP_MKDIR to CAP_MKDIRAT. Renamed CAP_MKFIFO to CAP_MKFIFOAT. Renamed CAP_MKNODE to CAP_MKNODEAT. CAP_READ old behaviour: - Allow pread(2). - Disallow read(2), readv(2) (if there is no CAP_SEEK). CAP_READ new behaviour: - Allow read(2), readv(2). - Disallow pread(2) (CAP_SEEK was also required). CAP_WRITE old behaviour: - Allow pwrite(2). - Disallow write(2), writev(2) (if there is no CAP_SEEK). CAP_WRITE new behaviour: - Allow write(2), writev(2). - Disallow pwrite(2) (CAP_SEEK was also required). Added convinient defines: #define CAP_PREAD (CAP_SEEK | CAP_READ) #define CAP_PWRITE (CAP_SEEK | CAP_WRITE) #define CAP_MMAP_R (CAP_MMAP | CAP_SEEK | CAP_READ) #define CAP_MMAP_W (CAP_MMAP | CAP_SEEK | CAP_WRITE) #define CAP_MMAP_X (CAP_MMAP | CAP_SEEK | 0x0000000000000008ULL) #define CAP_MMAP_RW (CAP_MMAP_R | CAP_MMAP_W) #define CAP_MMAP_RX (CAP_MMAP_R | CAP_MMAP_X) #define CAP_MMAP_WX (CAP_MMAP_W | CAP_MMAP_X) #define CAP_MMAP_RWX (CAP_MMAP_R | CAP_MMAP_W | CAP_MMAP_X) #define CAP_RECV CAP_READ #define CAP_SEND CAP_WRITE #define CAP_SOCK_CLIENT \ (CAP_CONNECT | CAP_GETPEERNAME | CAP_GETSOCKNAME | CAP_GETSOCKOPT | \ CAP_PEELOFF | CAP_RECV | CAP_SEND | CAP_SETSOCKOPT | CAP_SHUTDOWN) #define CAP_SOCK_SERVER \ (CAP_ACCEPT | CAP_BIND | CAP_GETPEERNAME | CAP_GETSOCKNAME | \ CAP_GETSOCKOPT | CAP_LISTEN | CAP_PEELOFF | CAP_RECV | CAP_SEND | \ CAP_SETSOCKOPT | CAP_SHUTDOWN) Added defines for backward API compatibility: #define CAP_MAPEXEC CAP_MMAP_X #define CAP_DELETE CAP_UNLINKAT #define CAP_MKDIR CAP_MKDIRAT #define CAP_RMDIR CAP_UNLINKAT #define CAP_MKFIFO CAP_MKFIFOAT #define CAP_MKNOD CAP_MKNODAT #define CAP_SOCK_ALL (CAP_SOCK_CLIENT | CAP_SOCK_SERVER) Sponsored by: The FreeBSD Foundation Reviewed by: Christoph Mallon <christoph.mallon@gmx.de> Many aspects discussed with: rwatson, benl, jonathan ABI compatibility discussed with: kib
* Style.pjd2013-02-251-8/+5
| | | | Suggested by: kib
* After r237012, the fdgrowtable() doesn't drop the filedesc lock anymore,pjd2013-02-251-3/+1
| | | | | | so update a stale comment. Reviewed by: kib, keramida
* Don't treat pointers as booleans.pjd2013-02-171-3/+3
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* Make the F_READAHEAD option to fcntl(2) work as documented: a value of zeroian2013-02-131-1/+1
| | | | | | | | now disables read-ahead. It used to effectively restore the system default readahead hueristic if it had been changed; a negative value now restores the default. Reviewed by: kib
* Remove label that was accidentally moved during Giant removal from VFS.pjd2013-01-311-3/+4
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* Rewrite fdgrowtable() so common mortals can actually understand whatdes2012-12-201-55/+74
| | | | | it does and how, and add comments describing the data structures and explaining how they are managed.
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