From 15c7e02e4a5fe127bd55bce2b9aa63a5da8eb228 Mon Sep 17 00:00:00 2001 From: Oswald Buddenhagen Date: Sun, 24 Nov 2024 13:11:32 +0100 Subject: [PATCH] accept zero-sized messages from IMAP while such a thing is rather pointless, completely empty messages are not forbidden. consequently, we should be able to deal with them, and above all not crash. Upstream-Status: Backport [https://sourceforge.net/p/isync/isync/ci/15c7e02e4a5fe127bd55bce2b9aa63a5da8eb228/] --- src/drv_imap.c | 5 ++++- src/socket.c | 1 - src/util.c | 5 +++++ 3 files changed, 9 insertions(+), 2 deletions(-) diff --git a/src/drv_imap.c b/src/drv_imap.c index 1280e3c..b0be1fd 100644 --- ./src/drv_imap.c +++ ./src/drv_imap.c @@ -780,6 +780,8 @@ parse_imap_list( imap_store_t *ctx, char **sp, parse_list_state_t *sts ) if (sts->callback->atom( ctx, NULL, bytes, AtomChunkedLiteral ) != LIST_OK) goto bail; sts->in_literal = ChunkedLiteral; + if (!bytes) + goto nobytes; sts->big_literal = 1; get_chunked: n = 1; @@ -806,7 +808,7 @@ parse_imap_list( imap_store_t *ctx, char **sp, parse_list_state_t *sts ) } else if (DFlags & DEBUG_NET_ALL) { printf( "%s=========\n", ctx->label ); fwrite( p, n, 1, stdout ); - if (p[n - 1] != '\n') + if (n && p[n - 1] != '\n') fputs( "\n(no-nl) ", stdout ); printf( "%s=========\n", ctx->label ); } else { @@ -819,6 +821,7 @@ parse_imap_list( imap_store_t *ctx, char **sp, parse_list_state_t *sts ) bytes -= n; if (bytes > 0) goto postpone; + nobytes: if (sts->in_literal == ChunkedLiteral && sts->callback->atom( ctx, NULL, 0, AtomLiteral ) != LIST_OK) goto bail; getline: diff --git a/src/socket.c b/src/socket.c index afd3f18..1ef0e95 100644 --- ./src/socket.c +++ ./src/socket.c @@ -952,7 +952,6 @@ socket_expect_bytes( conn_t *conn, uint len ) char * socket_read( conn_t *conn, uint min_len, uint max_len, uint *out_len ) { - assert( min_len > 0 ); assert( min_len <= sizeof(conn->buf) ); assert( min_len <= max_len ); diff --git a/src/util.c b/src/util.c index e697cfb..121ab0a 100644 --- ./src/util.c +++ ./src/util.c @@ -637,6 +637,11 @@ nfmalloc( size_t sz ) { void *ret; +#ifndef __GLIBC__ + // The C standard allows NULL returns for zero-sized allocations. + if (!sz) + sz = 1; +#endif if (!(ret = malloc( sz ))) oom(); return ret; -- 2.47.1