kernel/linux.git/lib/generic-radix-tree.c, branch v5.15.208

lib/generic-radix-tree.c: Fix rare race in __genradix_ptr_alloc()

2024-09-12T09:07:50+00:00

[ Upstream commit b2f11c6f3e1fc60742673b8675c95b78447f3dae ] If we need to increase the tree depth, allocate a new node, and then race with another thread that increased the tree depth before us, we'll still have a preallocated node that might be used later. If we then use that node for a new non-root node, it'll still have a pointer to the old root instead of being zeroed - fix this by zeroing it in the cmpxchg failure path. Signed-off-by: Kent Overstreet Signed-off-by: Sasha Levin

lib/generic-radix-tree.c: add kmemleak annotations

2019-10-14T22:04:00+00:00

Kmemleak is falsely reporting a leak of the slab allocation in sctp_stream_init_ext(): BUG: memory leak unreferenced object 0xffff8881114f5d80 (size 96): comm "syz-executor934", pid 7160, jiffies 4294993058 (age 31.950s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000ce7a1326>] kmemleak_alloc_recursive include/linux/kmemleak.h:55 [inline] [<00000000ce7a1326>] slab_post_alloc_hook mm/slab.h:439 [inline] [<00000000ce7a1326>] slab_alloc mm/slab.c:3326 [inline] [<00000000ce7a1326>] kmem_cache_alloc_trace+0x13d/0x280 mm/slab.c:3553 [<000000007abb7ac9>] kmalloc include/linux/slab.h:547 [inline] [<000000007abb7ac9>] kzalloc include/linux/slab.h:742 [inline] [<000000007abb7ac9>] sctp_stream_init_ext+0x2b/0xa0 net/sctp/stream.c:157 [<0000000048ecb9c1>] sctp_sendmsg_to_asoc+0x946/0xa00 net/sctp/socket.c:1882 [<000000004483ca2b>] sctp_sendmsg+0x2a8/0x990 net/sctp/socket.c:2102 [...] But it's freed later. Kmemleak misses the allocation because its pointer is stored in the generic radix tree sctp_stream::out, and the generic radix tree uses raw pages which aren't tracked by kmemleak. Fix this by adding the kmemleak hooks to the generic radix tree code. Link: http://lkml.kernel.org/r/20191004065039.727564-1-ebiggers@kernel.org Signed-off-by: Eric Biggers Reported-by: Reviewed-by: Marcelo Ricardo Leitner Acked-by: Neil Horman Reviewed-by: Catalin Marinas Cc: Kent Overstreet Cc: Vlad Yasevich Cc: Xin Long Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/generic-radix-tree.c: make 2 functions static inline

2019-09-26T00:51:39+00:00

When building with W=1, we get some warnings: l CC lib/generic-radix-tree.o lib/generic-radix-tree.c:39:10: warning: no previous prototype for 'genradix_root_to_depth' [-Wmissing-prototypes] 39 | unsigned genradix_root_to_depth(struct genradix_root *r) | ^~~~~~~~~~~~~~~~~~~~~~ lib/generic-radix-tree.c:44:23: warning: no previous prototype for 'genradix_root_to_node' [-Wmissing-prototypes] 44 | struct genradix_node *genradix_root_to_node(struct genradix_root *r) | ^~~~~~~~~~~~~~~~~~~~~ They're not used anywhere else, so make them static inline. Link: http://lkml.kernel.org/r/46923.1565236485@turing-police Signed-off-by: Valdis Kletnieks Cc: Kent Overstreet Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

generic radix trees

2019-03-12T17:04:02+00:00

Very simple radix tree implementation that supports storing arbitrary size entries, up to PAGE_SIZE - upcoming patches will convert existing flex_array users to genradixes. The new genradix code has a much simpler API and implementation, and doesn't have a hard limit on the number of elements like flex_array does. Link: http://lkml.kernel.org/r/20181217131929.11727-5-kent.overstreet@gmail.com Signed-off-by: Kent Overstreet Cc: Alexey Dobriyan Cc: Al Viro Cc: Dave Hansen Cc: Eric Paris Cc: Marcelo Ricardo Leitner Cc: Matthew Wilcox Cc: Neil Horman Cc: Paul Moore Cc: Pravin B Shelar Cc: Shaohua Li Cc: Stephen Smalley Cc: Vlad Yasevich Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds